Optimal Protocols for Studying & Learning

0:00:04 Welcome to the Huberman Lab Podcast, where we discuss science and science-based tools
0:00:06 for everyday life.
0:00:13 I’m Andrew Huberman, and I’m a professor of neurobiology and ophthalmology at Stanford
0:00:15 School of Medicine.
0:00:18 Today we are discussing how to study and learn.
0:00:24 That is, what the scientific data say is the best way to study in order to remember information
0:00:29 and to be able to use that information effectively in different areas of your life.
0:00:33 So for those of you that are still in school, this could be any stage of school, today’s
0:00:36 discussion will be very useful for you.
0:00:40 However, even if you are not formally enrolled in any kind of school at the moment, today’s
0:00:46 discussion will also be extremely effective for you to be able to study and learn better
0:00:52 information from, say, the internet or podcasts or any area of your life where you are seeking
0:00:56 to learn and use new knowledge.
0:01:00 Now one of the most important things that you’re going to learn today is that learning,
0:01:04 that is the best learning practices, are not intuitive.
0:01:11 So before we dive in, keep in mind that whatever you believe about how best to learn for you
0:01:13 is probably incorrect.
0:01:18 And I confess this was humbling for me as well when I started to dive into this literature
0:01:23 because as somebody who was a student for many years and in some sense still considers
0:01:28 himself a student of science and health information because of this podcast, and certainly as
0:01:32 somebody who still teaches university courses, both to medical students and graduate students
0:01:37 and to undergraduate students at Stanford, I thought I understood the whole teaching
0:01:42 and learning process, but I too learned that it is anything but intuitive.
0:01:49 In fact, most of what we believe about the best ways to study are absolutely false.
0:01:52 Fortunately today, you will learn the best ways to study.
0:01:56 Turns out there’s a rich literature on this dating back well over a hundred years and
0:02:00 the data are absolutely fascinating and incredibly actionable.
0:02:04 It’s incredibly interesting how the fields of education, the fields of psychology and
0:02:10 the fields of neuroscience have now come together to define the optimal strategies to study
0:02:11 and learn.
0:02:15 Before we begin, I’d like to emphasize that this podcast is separate from my teaching
0:02:17 and research roles at Stanford.
0:02:21 It is however part of my desire and effort to bring zero cost to consumer information
0:02:24 about science and science related tools to the general public.
0:02:28 In keeping with that theme, I’d like to thank the sponsors of today’s podcast.
0:02:30 Our first sponsor is AteSleep.
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0:02:39 I’ve spoken many times before on this podcast about the critical need to get sleep, both
0:02:41 enough sleep and enough quality sleep.
0:02:45 Now, one of the key things to getting a great night’s sleep is that your body temperature
0:02:49 actually has to drop by about one to three degrees in order for you to fall and stay deeply
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0:02:54 In order to wake up feeling refreshed, your body temperature actually has to increase
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0:03:00 One of the best ways to ensure all of that happens is to control the temperature of your
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0:04:06 Today’s episode is also brought to us by BetterHelp.
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0:05:19 Waking Up is a meditation app that offers hundreds of guided meditation programs, mindfulness
0:05:21 trainings, yoga-needra sessions, and more.
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0:06:49 Okay, let’s talk about how best to study and learn.
0:06:51 And of course, people have different learning styles.
0:06:54 Some people prefer to learn by reading.
0:06:55 Some people prefer to study in a group.
0:06:57 Some people prefer to highlight.
0:07:00 Some people call themselves auditory learners.
0:07:03 Other people consider themselves visual learners.
0:07:04 And guess what?
0:07:09 When one looks at the research on preferred learning styles, pretty much all of that melts
0:07:10 away.
0:07:16 It turns out that the best way to study and learn is defined not by the medium in which
0:07:20 that material arrives, whether or not it’s auditory or visual or combined, whether or
0:07:25 not you review slides or a textbook, or you watch small videos.
0:07:31 It turns out that the best way to study and learn is to access components of your memory
0:07:35 systems that offset forgetting.
0:07:39 This is a theme I’m going to return to over and over again throughout today’s episode.
0:07:45 Rather than think about studying to learn and retain information, I want you to think about
0:07:51 studying to offset the natural process of forgetting that everybody experiences when
0:07:57 they are exposed to new material of any kind, cognitive or motor learning, musical learning,
0:07:58 math, et cetera.
0:07:59 Okay?
0:08:01 So keep this in mind throughout today’s episode.
0:08:07 The best way to learn is to think about offsetting the natural forgetting of new information.
0:08:11 You’re trying to inoculate against forgetting.
0:08:12 That is the way to remember things.
0:08:15 That is the way to gain mastery over them.
0:08:21 And I’m going to teach you how to best do that using the data gleaned from the peer-reviewed
0:08:22 literature.
0:08:25 Now, before I do that, I want to talk about what learning is.
0:08:30 I promise to make this fairly brief because I’ve covered learning and so-called neuroplasticity
0:08:32 before on this podcast.
0:08:35 For those of you that have heard those discussions, this will serve as a refresher.
0:08:39 For those of you that have not heard those discussions, this will be thorough enough for
0:08:44 you to be able to digest all the rest of today’s information.
0:08:47 Neuroplasticity is this incredible feature of your nervous system, which of course includes
0:08:52 your brain and your spinal cord, which is the ability for your nervous system to change
0:08:54 in response to experience.
0:08:59 So any form of learning involves neuroplasticity.
0:09:05 We sometimes hear as neuroplasticity, two words, or neuroplasticity.
0:09:07 Those are the same thing, essentially.
0:09:12 The change that underlies neuroplasticity at the level of cells, which we call neurons
0:09:16 or nerve cells, generally involves three different mechanisms.
0:09:21 One is the strengthening of certain connections, what we call synaptic connections.
0:09:25 Synapses are the location between neurons where they communicate with one another.
0:09:27 It’s actually a gap between the neurons.
0:09:29 It is technically called the synaptic cleft.
0:09:30 It’s a gap.
0:09:35 And within that gap, chemicals are passed across that gap that allow one neuron to activate
0:09:41 other neurons or many neurons to activate many other neurons or to inhibit the activity
0:09:42 of other neurons.
0:09:49 So one form of neuroplasticity is the strengthening of connections between neurons.
0:09:54 Another form of neuroplasticity is the weakening of connections between neurons.
0:09:59 And yet a third form of plasticity, which is often discussed in the media, but is very
0:10:06 rare actually in the nervous system, especially the adult nervous system of humans, is neurogenesis
0:10:09 or the addition of new neurons.
0:10:13 Let’s just get this out of the way up front because the addition of new neurons, again,
0:10:19 grabs so much attention in media articles, but it’s responsible for a near-trivial amount
0:10:23 of the sort of neuroplasticity that is important for today’s discussion or, frankly, for most
0:10:24 all, discussions.
0:10:28 It is true you have a specialized set of neurons in your olfactory bulb that are responsible
0:10:33 for smell, as well as a specialized set of neurons in the so-called dentate gyrus of
0:10:38 your hippocampus, an area of the brain that’s important for memory, in which new neurons
0:10:41 appear to be added throughout the lifespan.
0:10:45 But this is not the major mechanism by which learning and memory occurs in humans.
0:10:50 Rather, the major mechanism by which learning and memory occurs in humans is the strengthening
0:10:56 of existing connections and the weakening of existing connections or the formation of
0:11:03 new connections between already existing neurons, not new neurons.
0:11:08 Now the removal or weakening of connections between neurons being an important component
0:11:12 of neuroplasticity is very important for sake of today’s discussion.
0:11:16 I want to emphasize that when we hear about weakening of connections, we often think, “Well,
0:11:20 that means forgetting,” or, “That means the brain is getting less good.”
0:11:25 However, so much of the neuroplasticity that underlies, for instance, the acquisition of
0:11:30 a new motor skill is actually the reflection of removal of connections.
0:11:37 So we don’t want to project any kind of value onto a discussion about adding new connections,
0:11:38 removing new connections.
0:11:41 Let’s just leave it at this level mechanistically.
0:11:47 When you hear about neuroplasticity, just know that it could be the consequence of strengthening
0:11:54 of connections as well as weakening of connections and that neither strengthening of connections
0:11:59 in the nervous system nor weakening of connections can map directly to the formation or removal
0:12:01 of, say, memories or information.
0:12:03 Just know that these are the important mechanisms.
0:12:10 In fact, if you look at a baby that is, let’s say, I don’t know, nine months old, their motor
0:12:14 skills are not terrific typically compared to the motor skills that that child will have
0:12:16 when they are six or seven years old.
0:12:20 Just look at a kid trying to eat spaghetti or something of that sort or eat anything
0:12:26 when they’re a small baby versus a toddler versus a young child versus an adolescent
0:12:27 or teen.
0:12:31 You know, despite the poor table manners of some adolescents and teens and some adults,
0:12:37 for that matter, they are still exhibiting far more precise motor movements than they
0:12:40 did as an infant, of course.
0:12:45 And believe it or not, the improvement in motor coordination that one observes in humans
0:12:51 and other species, for that matter, from birth until the adolescents and teen years and adult
0:12:54 years is largely the reflection of the removal.
0:12:55 That’s right.
0:13:00 The removal of neural connections as opposed to the formation of neural connections.
0:13:04 However, the neural connections that remain become much more robust.
0:13:05 They become much more reliable.
0:13:06 Okay.
0:13:10 So that’s the mechanistic backdrop for everything that we’re going to talk about today, which
0:13:12 is how to study and learn.
0:13:19 And as I mentioned earlier in my introduction, most of learning and remembering new material
0:13:23 is about offsetting the forgetting process that naturally occurs anytime we hear new
0:13:25 information.
0:13:30 So in keeping with what will ultimately reveal itself to be the dominant theme of today’s
0:13:36 discussion right now and for reasons that will become clear later, I want you to take
0:13:38 a brief quiz.
0:13:42 Now the moment people hear quiz or test, typically it spikes their adrenaline.
0:13:46 They start feeling stressed, but don’t worry, you’re going to keep your answers to yourself
0:13:49 and you’re doing this for a very specific purpose.
0:13:50 Here’s my question.
0:13:55 This is a two question quiz.
0:14:01 How many different ways mechanistically speaking does neuroplasticity occur?
0:14:08 Is it one mechanism, two mechanisms, or three mechanisms, or is it four or five?
0:14:10 Okay.
0:14:16 Can you name in your head two of the three major changes that the nervous system can
0:14:20 undergo, which are reflective of neuroplasticity?
0:14:22 Okay.
0:14:26 So the answer to question was, is that there are three different modes of neuroplasticity
0:14:29 as you recall or as you may not have been able to recall.
0:14:34 And by the way, if you were not able to recall the three different modes of neuroplasticity
0:14:37 or mechanisms underlying neuroplasticity, that is fine.
0:14:44 As you’ll soon realize, recognizing the errors in your information retention is another critical
0:14:50 and very useful way to retain more information, even if you got the answer wrong or you didn’t
0:14:51 know.
0:14:55 In fact, especially if you got the answer wrong or you didn’t know.
0:15:00 So the three ways are the strengthening of neural connections, second, the weakening
0:15:05 of neural connections, and third, through neurogenesis, the addition of new neurons.
0:15:06 Why did I provide this quiz?
0:15:07 Why did I test you?
0:15:13 Well, as you’ll soon learn, if you look across the total body of research on how best to
0:15:18 study and learn, it involves doing exactly what we just did, which is to periodically
0:15:22 stop and test yourself on the material that you learned.
0:15:27 Testing is not just a way of evaluating what knowledge you’ve acquired and which knowledge
0:15:30 you have not managed to acquire.
0:15:35 It also turns out to be the best tool for offsetting forgetting of any kind.
0:15:39 And I’ll go into the data that supports that statement in a moment.
0:15:41 So yes, today we’re going to get a little bit meta in the sense that we’re going to
0:15:47 be learning about optimal studying strategies and applying those as we go through this podcast
0:15:51 and know there will not be a test at the end, although you’re welcome to give yourself a
0:15:52 test at the end.
0:15:56 I’m going to provide you with an excellent zero cost, very fast tool that you can use
0:16:01 to evaluate your knowledge and your ability to study and learn better as a consequence
0:16:05 of having listened to this podcast versus had you not listened to this podcast.
0:16:09 So if ever there was an incentive to listen to the end, there it is.
0:16:12 Okay, let’s talk about some of the other practical aspects of studying and learning.
0:16:17 I know a lot of you out there who want to learn and want to come up with the best studying
0:16:21 strategies are trying to think about how to structure your day or how much to study or
0:16:23 when to study.
0:16:27 Let’s get the most important things out of the way first.
0:16:32 Neuroplasticity and learning, that is converting your studying efforts into retention of knowledge
0:16:34 is a two step process.
0:16:37 You probably heard about active engagement.
0:16:42 That’s just a fancy set of words for focus, for really attending to the information that
0:16:43 you’re trying to learn.
0:16:47 And it is very important anytime you’re trying to learn new information.
0:16:50 So focus goes with alertness.
0:16:52 You can’t be focused if you’re not alert.
0:16:55 This is prerequisite.
0:17:00 So you need to be alert and you need to be focused in order to pay attention to the information
0:17:01 that you’re trying to learn.
0:17:08 In fact, it is the process of being focused and attending that cues your nervous system
0:17:11 that something is important, that something’s different about whatever sensory experience
0:17:15 you happen to be having when you’re focused and attending, whether or not it’s the information
0:17:22 you’re hearing or that you’re looking at or both, that cue at the level of neurochemicals
0:17:27 in your brain and body signals to the neurons, hey, you’re going to have to change.
0:17:32 You’re going to have to alter your connections, either make them stronger or weaker or a combination
0:17:37 of those things in order to make sure that your nervous system can retain and use the
0:17:39 information at a future time.
0:17:44 So that’s step one, and of course, as a part of step one, most people, when they hear about
0:17:47 optimal studying strategies, they want to know, what should they do?
0:17:50 What should they take in order to learn better?
0:17:53 Well, here’s what everyone should take in order to learn better, which is a great night’s
0:17:59 sleep the night before, limiting your external stress, although some stress is good because
0:18:00 it cues up your alertness.
0:18:03 It actually allows you to remember certain things better.
0:18:05 We’ll talk about this a little bit later.
0:18:10 No one can remove all stress from their life, but we know one thing for sure, your ability
0:18:15 to be alert and focused is going to be greater if you slept well the night before.
0:18:20 So sleep is, without question, the best new tropic, the word new tropic means smart drug.
0:18:23 I don’t really like that term because learning involves all sorts of things.
0:18:25 It’s not just about being smart.
0:18:26 It’s about being able to attend.
0:18:30 It’s about sometimes being creative, flexible with ideas and information.
0:18:34 Here’s the point, you’re going to need to get your sleep right in order to be able to
0:18:37 study and learn at your absolute best.
0:18:40 I’ve done many episodes of the Huberman Lab podcast about sleep.
0:18:45 We have a newsletter about sleep, the details in a short PDF format, the various things
0:18:48 you can do to get your sleep optimized, so to speak.
0:18:52 You can find all that HubermanLab.com by putting sleep into the search function.
0:18:57 We don’t have time to discuss that material now, but get your sleep right so that you
0:19:01 can be alert and focused when it comes time to learn.
0:19:06 Now the process of being alert and focused on particular material that you want to learn
0:19:13 can be enhanced by just having a silent script within your head, silent meaning you’re not
0:19:17 saying it out loud, where when you sit down to learn, you’re looking at a book or you’re
0:19:21 listening to a lecture, perhaps a podcast like this, you’re thinking, okay, I need to
0:19:22 learn this.
0:19:23 I need to learn this.
0:19:27 You can voluntarily ramp up your level of focus and alertness by telling yourself that
0:19:29 information is important.
0:19:32 Just be a passive participant in learning.
0:19:37 This is the basis of active learning by expecting the information to be so interesting that
0:19:41 it pulls your level of attention and focus out of you, rather learn to engage your attention
0:19:46 and focus voluntarily, volitionally.
0:19:51 When we hear about ADHD, attention deficit hyperactivity disorder, we know that people
0:19:55 with ADHD can attend very rapidly.
0:19:59 They can really pay close attention for long periods of time if they like a given topic
0:20:03 or a given experience or activity.
0:20:08 They have serious challenges, however, engaging their attention and alertness if they are
0:20:12 not excited about an activity or information.
0:20:20 It is the hallmark of all good learners to be able to voluntarily force yourself to attend
0:20:21 and to focus.
0:20:26 When I say force yourself, that means a constant bringing back of your mind’s attention to
0:20:28 whatever it is you’re trying to learn.
0:20:31 It is meant to feel difficult.
0:20:36 I say meant to feel difficult because that strain that you feel that encouraging or in
0:20:40 some cases forcing yourself to attend, sometimes even putting on a hoodie and hat, literally
0:20:45 putting blinders so that you can only attend to the material right in front of you.
0:20:51 That straining that you feel reflects in part the release of neuromodulators like epinephrine,
0:20:56 adrenaline in the brain and body, which serve to cue the neural circuits that they need
0:20:58 to change at a later time.
0:21:02 The strain that you feel in trying to learn, the strain that you feel in forcing yourself
0:21:04 to learn how to focus, that is good.
0:21:09 That’s a cue to your nervous system that it’s going to need to change, that neuroplasticity
0:21:11 needs to take place.
0:21:12 Think about it.
0:21:16 If you didn’t feel that strain and you were able to perform whatever it is that you were
0:21:21 doing or remember whatever information it is that you’re being exposed to seamlessly,
0:21:25 well then your nervous system wouldn’t have to change because it already has the capabilities
0:21:27 within the neural circuits.
0:21:31 That strain that you feel, that agitation is great.
0:21:38 That’s a cue that you are learning or that you’ve set the learning process in motion.
0:21:43 It’s also the case that some people don’t have great levels of focus and attention.
0:21:45 There are of course pharmacologic tools.
0:21:49 I would encourage anyone that has clinically diagnosed ADHD to talk to their doctor about
0:21:54 whether or not they should use prescription meds and/or other methods.
0:21:58 Great sleep is always going to be an important substrate for attention and focus for anybody,
0:22:02 but especially for people with ADHD.
0:22:07 I highly encourage anyone that’s interested in enhancing their levels of focus and attention
0:22:11 to also consider the non-pharmacologic approaches.
0:22:14 This is irrespective of whether or not you need pharmacologic approaches.
0:22:15 Yes, being well hydrated.
0:22:20 Yes, the appropriate amount of caffeine for you that allows you to be alert but not shaking
0:22:23 and agitated can be very useful.
0:22:31 However, the scientific data also support the fact that doing a brief say five to 10-minute
0:22:35 mindfulness meditation each day, these are the data from Wendy Suzuki’s laboratory at
0:22:41 New York University showing that people who do a 10-minute meditation per day where they
0:22:46 simply sit or lie down, close their eyes, focus on their breathing, their attention invariably
0:22:49 drifts, they bring their attention back to their breathing.
0:22:54 People who do that on a regular basis improve their level of focus, they improve their memory
0:22:59 and recall ability, and of course there are a bunch of other positive effects of that simple
0:23:03 zero-cost tool of mindfulness meditation.
0:23:07 If you’re interested in improving your levels of focus and attention for sake of learning,
0:23:15 I highly encourage you to explore the oh-so valuable tool of mindfulness meditation just
0:23:18 five or 10 minutes per day done on a regular basis.
0:23:21 You miss a day, no big deal, just get right back to it the next day.
0:23:25 Does it matter if you do it morning, afternoon, or night?
0:23:26 No.
0:23:29 Some people find that doing it too late at night might disrupt their sleep, but if you
0:23:34 think about meditation of the sort that I just described as a perceptual exercise, maybe
0:23:37 you don’t even call it meditation, you’re just teaching yourself to focus.
0:23:42 You could even do it with eyes open by focusing on a visual target, allowing yourself to blink.
0:23:46 There are good data on this sort of approach as well, and then just making sure that your
0:23:52 visual attention and cognitive attention comes back to that visual target over and over again.
0:23:58 It’s a deliberate process of bringing your attention back to a particular location.
0:24:01 That is very valuable for improving your levels of focus.
0:24:06 In fact, it is known to create significant improvements in your ability to focus, which
0:24:09 is critical for your ability to study and learn.
0:24:14 I know that many people are interested in what to take, what to do at the level of kind
0:24:17 of esoteric practices or things to buy.
0:24:18 There is stuff out there.
0:24:23 Again, I mentioned hydration, caffeine, great sleep, and so on, but the simple practice of
0:24:29 mindfulness meditation or just what I describe as a focusing perceptual exercise of bringing
0:24:33 your attention back to the same location over and over again deliberately will train you
0:24:37 to train your nervous system to bring your attention back to whatever it is you’re trying
0:24:38 to learn.
0:24:43 Now, I’ve done other podcasts about how to focus, about attention specifically, and ADHD.
0:24:49 Again, you can find all of those at hubermanlab.com, simply put ADHD or focus or tools for focus
0:24:50 into the search function.
0:24:55 It will take you to the exact timestamps in those episodes that are relevant.
0:25:00 Right now, however, I want to talk about the second part of neuroplasticity, which is
0:25:05 that the actual changes in the nervous system, the strengthening and weakening predominantly
0:25:10 of connections between neurons that underlie learning, do not occur during the focusing
0:25:16 and learning or rather the exposure to the material, but instead during deep sleep and
0:25:17 sleep-like states.
0:25:21 Again, I’ve done a lot of podcasts and talked a lot about tools for getting better sleep,
0:25:25 but I just want to remind everybody that the actual reordering of the connections, the
0:25:29 strengthening of connections between neurons that underlie learning, the weakening of those
0:25:34 connections occurs during sleep in particular during rapid eye movement sleep, which tends
0:25:37 to predominate in the latter half of the night.
0:25:40 Make sure that you’re getting enough sleep for you for some people at six hours or some
0:25:41 people at eight hours.
0:25:44 Yes, there is something called the first night effect.
0:25:50 The first night effect is the experimentally observed phenomenon whereby information that
0:25:56 you learn on a given day is mostly consolidated during the night sleep that you have on that
0:25:59 first night after the learning occurs.
0:26:02 Does this mean that if you get a poor night sleep on the first night after learning something
0:26:08 that you are forever going to forget, that information, that it cannot be consolidated
0:26:09 into your neural circuits?
0:26:10 No.
0:26:16 It’s very clear that the first night after learning you want to get the best sleep possible.
0:26:20 So if you’re learning about your studying is going late into the night and you’re drinking
0:26:24 a lot of caffeine, be mindful that the sleep that you get after drinking that caffeine late
0:26:28 into the day, the all-nighters that you’re pulling, those are not serving your learning
0:26:29 well.
0:26:36 So you need to structure your life as a student of any kind so that you can get focus and
0:26:39 attention to what it is you want to learn and you can get sleep to the best of your
0:26:40 ability.
0:26:44 And of course, people who are raising young kids or who have stress in their lives for
0:26:48 whatever reason, perhaps won’t be able to optimize their sleep on that first night or
0:26:51 even subsequent nights, but do your best to get your sleep right.
0:26:55 It’s the single best thing you can do for your mental health, for your physical health,
0:27:00 and for learning and performance of any kind, and it’s really worth the effort.
0:27:09 Now, with an understanding of the mechanisms, the focus and alertness and the sleep phase
0:27:14 of neuroplasticity, what are some other things that you can do to enhance whatever studying
0:27:16 and learning you’ve obtained?
0:27:19 I already talked about a tool, a behavioral tool for enhancing focus.
0:27:24 What about a behavioral tool for enhancing plasticity if your sleep is great or especially
0:27:25 if your sleep isn’t great?
0:27:30 And there, I highly recommend you explore non-sleep deep rest or NSDR.
0:27:32 There’s a script for this in the show note captions.
0:27:38 NSDR, sometimes referred to as yoga-needra, although those things are similar but different,
0:27:43 is a 10 or 20 minute practice that you can do to restore your mental and physical vigor.
0:27:45 If you haven’t slept enough, so you could do it first thing in the morning when you
0:27:46 wake up.
0:27:49 If you feel you haven’t slept enough, you can do it in the afternoon.
0:27:53 You can do it in the middle of the night if you’re not able to sleep and offset some of
0:27:56 the sleep loss that you otherwise would have experienced.
0:28:02 NSDR is a very powerful tool in order to enhance neuroplasticity.
0:28:04 And I’ll talk more about this in a future episode.
0:28:08 There’s a lot of exciting data coming out about NSDR and yoga-needra.
0:28:13 But if you’re sleeping well and even if you aren’t, I highly encourage you to incorporate
0:28:17 a 10 or 20 minute NSDR into your schedule someplace.
0:28:20 Again, where you place it in your schedule isn’t as important as the fact that you do
0:28:24 it in order to enhance neuroplasticity.
0:28:28 That is, the reordering of connections between neurons to serve the studying and learning
0:28:29 that you’re doing.
0:28:32 Now let’s talk about how the best students structure their days.
0:28:35 Turns out there are great studies on this.
0:28:42 There’s a really nice paper, in fact, that surveyed close to 700 students.
0:28:49 These were medical students, approximately equal number of male and female students,
0:28:51 and analyzed the most useful learning habits.
0:28:55 That is, the learning habits associated with the most successful students.
0:28:59 Now anytime you do a study like this where people take surveys, there’s always the issue
0:29:00 of causality.
0:29:04 In fact, we can pretty much set aside any possible causality.
0:29:07 For instance, I’m about to tell you that the very best performing students tend to study
0:29:10 for about three or four hours per day.
0:29:14 But you could easily say, well, they’re the best students because they study three or
0:29:15 four hours per day.
0:29:18 They don’t study three or four hours per day because they’re the best students.
0:29:20 They need to be exactly right.
0:29:24 We can get into all sorts of discussions about correlation versus causation, about reverse
0:29:26 causality, and on and on.
0:29:28 However, none of that is the point here.
0:29:33 The point here is to establish what are the habits that the most successful students seem
0:29:37 to incorporate over and over again, regardless of what classes they’re taking, regardless
0:29:42 of where they are in their arc of their learning trajectory.
0:29:46 What we know, based on this study, and I’ll provide a link to it in the show note captions,
0:29:50 is that there are at least 10 study habits that the highly effective students use.
0:29:55 I’m going to focus on the top five or six just for sake of time because it turns out
0:30:01 that most of the effect it appears of being a better student can be attributed to these
0:30:03 top five or six habits.
0:30:06 First of all, they set aside time to study.
0:30:08 They literally schedule time to study.
0:30:10 Now, this probably serves several roles.
0:30:16 The first one is that they are able to clear out other distractions, and in fact, that’s
0:30:17 the second thing that they do.
0:30:22 They are very effective, or they make it a point of putting their phone away and off,
0:30:23 of isolating themselves.
0:30:24 That’s right.
0:30:26 They’re not studying with other people.
0:30:30 They study alone, which is not to say that people who study with others cannot be effective
0:30:35 in their studying, but the best performing students seem to study alone.
0:30:36 They put their phone away.
0:30:41 They tell their friends and families that they are not going to be able to be reached
0:30:43 during that time.
0:30:48 Yes, they study for three or four hours per day, but they break that up into a couple
0:30:52 of different sessions typically, two or three sessions, so they’re not doing a three or
0:30:56 four hour studying about all in one shot.
0:30:58 They’re managing their time.
0:31:04 They’re eliminating distractions, and they’re studying for a consistent amount of time at
0:31:08 least five days per week, presumably they’re taking some weekends off, although that wasn’t
0:31:09 made clear from this paper.
0:31:13 The other thing that they do, and this is very important, is that they make an effort
0:31:17 to then teach their peers, to teach other students in the class.
0:31:21 Some of you may be thinking, and I’m thinking back to college here mostly, that if you spend
0:31:25 all this time learning the information and you are in a competitive scenario with the
0:31:29 other students, that teaching them the information is kind of a freebie for them and is harder
0:31:33 for you, meaning you’re putting yourself at a competitive disadvantage or you’re giving
0:31:36 them an unfair advantage for not having done the work.
0:31:40 Now, while this paper didn’t do an analysis of whether or not these students that served
0:31:46 as the learners from the other students got an unfair advantage, it’s very clear that
0:31:50 students who make it a point to learn material in isolation, then bring that material to
0:31:55 other students in the same course and teach them, perform exceedingly well in comparison
0:31:56 to the other students.
0:32:03 So, don’t be afraid to be a teacher of your peers in order to test, this is key to test,
0:32:06 and develop mastery of the material.
0:32:11 Now, in my laboratory for years, we used to have a saying, which I simply picked up from
0:32:15 the laboratories I was trained in, I didn’t come up with the saying, which was watch one,
0:32:16 do one, teach one.
0:32:21 And that was referring to doing surgeries or suturing or doing an antibody reaction or
0:32:25 a Western blood or things that you do in laboratories.
0:32:27 Watch one, do one, teach one.
0:32:30 Watch one, do one, teach one, of course, should be reserved to anything where no one’s going
0:32:34 to be put in danger by the watch one, do one, teach one procedure, right?
0:32:39 Some procedures, especially in laboratories, can be dangerous given the materials you use,
0:32:40 et cetera.
0:32:42 And of course, today, we’re talking about learning and studying generally.
0:32:49 So, provided it’s safe, watch one, do one, teach one, is an excellent means to learn,
0:32:53 that is to study new material to develop proficiency and even mastery.
0:32:55 And over time, perhaps even virtuosity.
0:32:58 We’ll return to that later, those distinctions.
0:33:03 So, going back to this idea that the best students set aside time, they designate time
0:33:07 to study alone without distractions.
0:33:10 That is sure to help them anchor their focus and attention.
0:33:14 They know that they’re going to need to use their focus and attention during that time.
0:33:21 And we know with absolute certainty that focus and attention are a limited but renewable resource
0:33:22 in the human brain.
0:33:26 The longer you’re awake, the more is the buildup of a molecule called adenosine in your
0:33:27 brain and body.
0:33:28 It makes you sleepy.
0:33:29 It makes it harder to focus.
0:33:32 When you sleep, adenosine levels are pushed down again.
0:33:33 You’re able to focus again.
0:33:34 You feel more alert.
0:33:38 You can think of adenosine as limiting your attentional budget, which is not to say that
0:33:43 some people don’t study best in the afternoon or in the evening or even late at night, right?
0:33:47 I recall times during university when I’d study between the hours of 10 p.m. and 2 a.m.
0:33:53 I don’t do that any longer, but scheduling time where you know you’re going to need to
0:33:59 be focused and attending is perhaps one of the most important things toward being able
0:34:01 to focus and attend to the material.
0:34:05 Now, if you’re taking courses, you probably are going to be a slave to the timing of the
0:34:06 courses.
0:34:09 You aren’t going to be able to tell the instructor, “Okay, listen, I want you to do this course
0:34:13 at 3 p.m. because that’s when you learn best,” or at 8 a.m. because that’s when you happen
0:34:15 to be able to attend best.
0:34:19 However, to the extent that you have any control over the time in which you’re going to study,
0:34:23 keeping that at a regular time or times, perhaps one block early in the day, one block later
0:34:28 in the day, perhaps two blocks early in the day, and so on, is going to be beneficial.
0:34:32 It turns out that’s also supported by the research literature.
0:34:39 The brain, just like with its sleep/wake cycles that entrain to a regular schedule, that is,
0:34:44 your brain and body get used to being active and inactive at particular times based on
0:34:48 your exposure to sunlight, your exposure to activities, your social rhythms, et cetera.
0:34:54 If you regularly, meaning for the course of about three days, make it a point to focus
0:34:57 and study at particular times, again, pulling your attention back.
0:35:01 It’s not an automatic process, but pulling your attention back to a specific location,
0:35:06 perhaps on a page or that you’re listening to in lecture, your body and brain will start
0:35:13 to entrain to that rhythm such that you will be able to focus and attend better simply by
0:35:18 virtue of the regularity of the timing of the exposure to the material.
0:35:22 You probably need about two or three days to break into a regular schedule of focusing
0:35:27 and attending and studying at a given time or times.
0:35:31 Allow yourself that transition period, but then make it a point to schedule those times
0:35:37 to study, set aside your phone, tell people you’re going offline, turn off the Wi-Fi if
0:35:39 you need to or have to.
0:35:40 You may need it for your studying.
0:35:41 I don’t know.
0:35:45 It depends on what you’re studying, but limit distractions at all costs and learn to just
0:35:47 focus on the material.
0:35:48 This is a skill.
0:35:50 This is the most important thing to understand.
0:35:53 It’s a skill to be able to focus and study.
0:35:57 It’s a skill that you can learn very quickly, especially if you schedule it for regular
0:36:02 times and you give yourself two or three days in which to adapt to those schedules and times
0:36:06 and then try and stick to them as regularly as possible, perhaps even on the weekends
0:36:12 if you’re approaching the end of the quarter or semester, perhaps even on the weekend even
0:36:14 if you’re not in the quarter or semester.
0:36:20 Keeping those regular times will entrain your nervous system to study and learn at its best
0:36:21 at those particular times.
0:36:25 I’d like to take a quick break and acknowledge our sponsor, AG1.
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0:37:40 Before I move into specific ways to study in order to maximally offset forgetting, notice
0:37:46 I didn’t say in order to learn, but rather to maximally offset forgetting, aka learning,
0:37:48 stably learning material.
0:37:52 There’s one other point that I wanted to pass along from this really nice study on the study
0:37:57 habits of highly effective medical students that I’ve been referring to.
0:38:04 That is, when one examined or these people were asked about their motivation for studying,
0:38:07 the best performing students had an interesting answer.
0:38:15 They had a very long-term understanding of how or belief, rather, about how their success
0:38:21 in medical school would impact their family, how it would impact their life arc, how it
0:38:25 would change them, and they weren’t particular about the ways in which it would change them
0:38:26 or their family.
0:38:33 In fact, it was a rather broad, abstract, aspirational way of thinking about their study efforts.
0:38:38 What I like so much about this paper is that in addition to having a fairly large sample
0:38:44 size, close to 700 students that were evaluated, yes, it’s purely self-report and this kind
0:38:50 of thing, nonetheless, it bridges the two extremes of studying and learning.
0:38:54 It gets right down into the nitty gritty of how long they study, when they study, the
0:38:59 things they do to limit distraction that we just discussed, but it also gets to their
0:39:03 underlying psychological motivations and the thing that they use in order to pull them
0:39:09 forward through their study efforts, perhaps especially when their desire is waning or
0:39:12 their level of fatigue is increasing.
0:39:17 I don’t know that I’m speculating here, but this is this aspirational component of going
0:39:21 to medical school, which it turns out in the country in which the study was done, only
0:39:26 very, very select few of the very best students are able to achieve that.
0:39:31 They have to learn the information in a different language altogether, which is incredible.
0:39:32 I always marvel at that.
0:39:37 I have friends that did their PhD thesis in Italy, they’re Italian by birth.
0:39:42 They now happen to run a laboratory in Italy, and they had to do their PhD training and
0:39:47 write papers and give their thesis dissertation and defense in English, even though English
0:39:49 was their second language.
0:39:54 Talk about a challenge, and that’s just one example that I can think of.
0:39:57 There are many examples of that.
0:40:02 These students that I’m referring to in this study are not necessarily constantly thinking
0:40:08 about how their efforts will transform themselves and their families, but they certainly were
0:40:13 able to report what it was specifically that they are seeking, what they’re aspiring to,
0:40:18 besides just trying to do as well as they can getting into and through medical school.
0:40:23 The high level aspirational stuff within you, whatever that is for you, it’s going to be
0:40:30 highly individual, is certainly important, and it offers a bookend to the nuts and boltsy
0:40:34 kind of stuff that you’re going to do, I would hope, in order to best study and learn the
0:40:38 specific material, so the specific actions that you’re going to take each day to learn
0:40:43 specific bits of information that will pull you toward those important aspirations.
0:40:48 Now again, if you love the material you’re learning, this aspirational component is probably
0:40:50 not as important.
0:40:55 I can recall during university and graduate school and so on thinking, “Oh my goodness,
0:40:57 this is like the coolest thing I’ve ever heard.”
0:41:01 I’d probably say that about a million different topics like, “Oh my goodness, circadian rhythms,
0:41:03 seasonal rhythms, melatonin, neural circuits, dopamine.”
0:41:07 I was just awash with excitement about what I was learning, but of course, sometimes I
0:41:10 would take a course where the material was, I don’t know if it was more challenging or
0:41:15 not, but I had a harder time getting engaged by the material, either by virtue of how it
0:41:18 was being taught to me or the material itself.
0:41:24 So the ability to attach to some aspirational goal to pull you through can be very valuable.
0:41:27 You’re not going to love every topic you have to learn.
0:41:33 However, I will say that at least in my experience, some of the courses that I look back on most
0:41:38 fondly are the courses that I struggled with the most, and in fact, that’s the basis of
0:41:43 the next and easily one of the most important studying tools.
0:41:49 So a key theme in all of the excellent literature that is the peer reviewed research on how best
0:41:54 to study is that studying that feels challenging is the most effective.
0:41:57 I know nobody wants to hear this.
0:41:59 Everyone wants to hear about flow.
0:42:03 Everybody wants to hear about information just sinking into their brain by osmosis.
0:42:07 I think it was a Garfield cartoon where he talked about learning by osmosis.
0:42:11 There’s this very cute real world video of a kid in a classroom.
0:42:15 I believe it’s in China where he’s taking the book and he puts it on his head.
0:42:18 Maybe I can find this clip and he’s just kind of like trying to wash it into his brain.
0:42:20 It’s super cute clip, but guess what?
0:42:21 That doesn’t work.
0:42:22 I mean, it works to put the book on your head.
0:42:23 It doesn’t work.
0:42:27 It’s not going to get the information into your brain.
0:42:31 Perhaps someday there will be ways to rapidly download information into neural circuits.
0:42:40 Right now we know, we’ve known for hundreds, if not thousands of years, that effort is
0:42:42 the cornerstone of learning.
0:42:43 So I know there are probably some groans about that.
0:42:47 I know some of you perhaps were hoping that today I was going to tell you how to study
0:42:50 so that studying wasn’t painful.
0:42:55 I think I can accomplish that by the end of today’s episode, but in order to do that,
0:42:56 let’s take another quiz.
0:42:57 Okay.
0:42:58 So here’s the quiz.
0:43:00 Again, you can answer these questions in your head.
0:43:04 You don’t have to tell anyone, but you could write them down or say them out loud if you
0:43:05 want.
0:43:14 The next question is, when, during either your states of alertness or sleep, does the
0:43:17 remodeling of neural connections occur?
0:43:19 I like to think this is a pretty easy one.
0:43:20 Okay.
0:43:22 The answer is during sleep.
0:43:31 The second question is, what is one behavioral tool that you can use to improve focus?
0:43:35 The answer is simple mindfulness meditation, which I’d prefer you think of simply as a
0:43:36 perceptual exercise.
0:43:40 So again, just sit or lie down, close your eyes, focus on your breath.
0:43:45 When your attention drifts, bring your attention back to your breath and so on.
0:43:50 Or if you prefer, you can do this eyes open by focusing on a visual target, either a foot
0:43:54 or two feet or three feet away, whatever distance is comfortable for you, allowing yourself
0:44:00 to blink as needed, but forcing yourself to focus on that visual target for say one to
0:44:04 three minutes, maybe even three to five minutes, maybe even 10 minutes, again, please blink.
0:44:06 You don’t want your eyes to dry.
0:44:11 Both those tools will improve your ability to attend, to focus, to other material when
0:44:12 the time comes.
0:44:13 Okay.
0:44:18 The circuits for focus and attention themselves are subject to neuroplasticity.
0:44:24 And then the third question is, can you name or list off in your mind three tools that the
0:44:28 most effective students have been shown to use?
0:44:35 I can think of limiting distraction by virtue of putting away phones and telling others
0:44:37 you won’t be in contact with them too.
0:44:42 And I’m getting these out of order, I realize, is to isolate, to study alone.
0:44:49 And the third that I can recall is to teach others in the same course.
0:44:50 Okay.
0:44:52 You can probably think of a few others.
0:44:55 Now, why are we taking these silly little quizzes?
0:45:01 Well, turns out they’re not so silly when one considers that hopefully you’ll remember
0:45:06 the information from today so that you don’t have to listen to it over and over again,
0:45:13 but that if ever there was a strongly research supported tool in the literature, in the peer
0:45:19 reviewed literature about how students can learn information better, it’s testing.
0:45:25 And I know, I know, I know we think of tests as a way to evaluate our knowledge, but it
0:45:29 turns out that testing is one of the best ways to build our knowledge, to retain our
0:45:33 knowledge and again, to offset forgetting.
0:45:39 Now, the study of testing as a learning tool, not just as a way to evaluate how much information
0:45:42 we’ve learned goes back over a hundred years.
0:45:49 There’s a classic study that was done in 1917 where grade school age children read biographies.
0:45:55 So they read biographies and then the kids were divided into different groups.
0:46:01 One group read and reread and reread those biographies over and over.
0:46:07 Another group read the biographies once and then were tested on those biographies.
0:46:13 But get this, they tested themselves on those biographies simply by having to think about
0:46:17 the information that they had read and trying to remember the information, like what was
0:46:18 the biography?
0:46:19 Who was the person?
0:46:20 Who were they married to?
0:46:21 What did they do?
0:46:22 When did they go to school?
0:46:23 What did they do in school?
0:46:25 What did they do in the world?
0:46:27 What role did they play in life?
0:46:32 So they essentially tested their own knowledge simply by going into their own head and asking
0:46:35 themselves what they could remember about those biographies.
0:46:43 Now keep in mind here that even though it’s fairly apparent that reading a biography two,
0:46:49 three, four times might seem more passive than testing oneself on a biography that they
0:46:51 had read just once.
0:46:55 You could imagine that thinking about the biography involves more effort and indeed
0:46:56 it does.
0:47:00 But keep in mind also that the kids in the second group were only exposed to the biography
0:47:08 once and yet when you look at the percent of accurate recall of information from those
0:47:16 biographies, the children that read the biography once and then made a deliberate point to think
0:47:20 about that biography in their own mind to effectively test themselves on that material
0:47:23 just within their heads over and over.
0:47:28 But an equal number of times as the kids that read the biographies directly on a page over
0:47:34 and over vastly outperformed the kids that read the biographies over and over put differently.
0:47:41 Reading and rereading material and rereading material is far less effective than reading
0:47:46 material and then thinking about that material, testing yourself on that material, forcing
0:47:51 yourself to bring that material to mind in your own mind and this is not just for sake
0:47:59 of remembering more volume of material but also accuracy of recall of that material.
0:48:04 And that at least to me was pretty surprising at first until one starts to explore subsequent
0:48:08 studies of the role of testing as a learning tool.
0:48:13 And then you start to realize that testing yourself is far and away the best tool for
0:48:19 studying and learning not just for evaluating your knowledge but for actually studying and
0:48:22 incorporating that knowledge into your neural circuits.
0:48:23 Okay.
0:48:27 So I realize that anytime I or somebody else talks about a study that was done in 1917,
0:48:33 we think of people in these, you know, like wooden shoes and in these schoolhouses that
0:48:36 look so different and kids dress so different.
0:48:39 Let’s get a little more modern here.
0:48:43 Keep in mind, however, that the nervous system hasn’t really changed much in tens of thousands
0:48:45 of years.
0:48:51 Nonetheless, I think it’s nice to think about a more recent study of how best to study.
0:48:55 And this study, which by the way, we’ll provide a link to in the show note captions as well
0:48:58 as a couple of reviews that include results from similar studies.
0:49:04 Again, I’m pointing to a body of research, not just one study here.
0:49:12 Based at whether or not studying material four times, so study, study, study, study
0:49:19 was better in terms of locking that information into people’s minds, allowing them to use
0:49:23 that information flexibly, which is an element of creativity, essentially given the mastery
0:49:29 of the material, then a different group, which studied once, studied the material twice,
0:49:37 studied the material three times, then was tested on the material or a third group that
0:49:45 studied material once, then took one, two, yes, three tests on the material.
0:49:49 Now, so what I just described was three groups, all of whom read a passage.
0:49:55 This was a passage about animals, about biology, some other topics too in different experiments.
0:49:59 Again, three groups, one group studies four times.
0:50:06 They study the material one, two, three, four times, then later they take a test.
0:50:13 The second group studies one, two, three times, takes a test on that material, and then later
0:50:14 takes a test.
0:50:19 The third group studies the material once, then takes three tests on the material, and
0:50:21 then later takes a test.
0:50:26 So what’s analyzed and compared between these different groups is their performance on that
0:50:28 final test.
0:50:36 What I put in as the fifth bin there, because think about it as SSSS, so study, study, study,
0:50:43 and then later test, or SSST, study, study, study, test, and then later test, or STTT,
0:50:45 study, test, test, test, and then later test.
0:50:50 So what’s compared and contrasted is performance on the test some period of time later.
0:50:56 Now some experiments made that final test of the material a couple days later.
0:50:59 Other experiments made it a couple weeks later.
0:51:04 Other experiments made it much later, months or even a year later.
0:51:07 The point here is twofold.
0:51:12 First of all, based on everything I’ve told you thus far, you can probably guess who performed
0:51:18 best on the test that occurred some period of time later.
0:51:19 Right.
0:51:27 The performance on that final test was essentially proportional to the number of tests one had
0:51:29 already taken on the material.
0:51:34 That should be pretty much obvious given the way we’ve been going today in this description
0:51:37 of tests as a way to offset forgetting.
0:51:38 Okay.
0:51:43 So the more tests that you take as a way to expose yourself to the material, the better
0:51:46 you’re going to perform on that material at some later point.
0:51:49 Now of course, at some point you have to be exposed to the material for the first time.
0:51:50 Right.
0:51:52 That’s why it’s studying and learning.
0:51:56 But after one exposure to new material, taking more tests on that material, even if you don’t
0:52:02 perform that well on those tests, as long as you’re able to see the accurate answers
0:52:06 to those tests and compare your answers to those answers will lead to better performance
0:52:11 on the ultimate test and retention of that material at some later time.
0:52:16 Put differently, it’s not about how many times you study the material or how many times
0:52:18 you’re exposed to the material.
0:52:22 It’s about being exposed to the material, doing your best to focus and attend to that
0:52:26 material and then self-testing yourself on that material.
0:52:31 Or as the case may be if an instructor is the one giving you the test, but nonetheless
0:52:37 taking tests on that material, not just once, but ideally two or three times, that’s what
0:52:41 really locks the material into your neural circuits.
0:52:47 That’s what’s going to lead to the most pervasive change, the most durable change we should say,
0:52:51 in your neural circuits that carry that material, that hold that material in your mind, what
0:52:55 we call neural encoding.
0:52:59 So the more times you test yourself or that you are tested on material, the better your
0:53:01 retention of that material.
0:53:05 Now some people will immediately say, “Well goodness, what if I learned it and then I’m
0:53:10 tested and I’m somehow consolidating the wrong or inaccurate material?”
0:53:11 But it doesn’t appear to be the case.
0:53:16 As long as you learn what the correct answers to the tests are, even if you’re getting 40
0:53:23 or 50% or less accurate on those tests that you take immediately after the studying period,
0:53:28 that’s still going to be a better strategy than rereading the material, which ought to
0:53:29 be somewhat surprising.
0:53:31 It certainly was surprising to me.
0:53:34 But you know what’s even more surprising and a little scary and that we all should know
0:53:41 and I wish I had learned when I was like in the second grade is that if you ask students,
0:53:46 how confident are you in the material that you just learned?
0:53:48 How well do you think you would perform on a test?
0:53:54 What you see consistently in these studies, I’m chuckling, because it’s kind of mind-blowing
0:53:58 is that the students who studied the material, that is, who were exposed to the material
0:54:04 four times think that they are going to perform best on the ultimate exam.
0:54:09 However, the students that study the material once and then are tested three times on that
0:54:17 material, they think that ultimately they’re going to perform least well.
0:54:19 For instance, they ask them their confidence, “How well do you think you would perform
0:54:25 on a test of this material in two weeks or in a year or in six months or even tomorrow?”
0:54:32 They report, that is, the students in the study test, test, test group report much lower
0:54:37 confidence in the material, much lower sense of mastery of the material compared to the
0:54:40 students that were exposed to the material four times who were saying, “Yeah, I think
0:54:44 I would do pretty well or very well,” and guess what?
0:54:45 The exact opposite is true.
0:54:50 Put differently, when you’re exposed to material over and over and over again, you think you’ve
0:54:51 learned the material.
0:54:56 In fact, your confidence that you’ve learned the material increases with each subsequent
0:55:01 exposure to the material, but actually, you haven’t learned it at all compared to the
0:55:06 people that are exposed to the material and then take tests on the material, oftentimes
0:55:09 straining to get the answers right on those tests.
0:55:14 In fact, sometimes getting those answers dead wrong and then realizing they get those answers
0:55:17 dead wrong or sometimes they just sense it, but guess what?
0:55:23 Testing yourself once, twice, maybe three times prior to the ultimate test of your knowledge
0:55:29 of that material is far and away the best way to lock that material into those neural
0:55:30 circuits.
0:55:34 Now, I say I wish I had learned this when I was a student because to some extent I used
0:55:37 a self-testing approach.
0:55:43 The one most salient example of that is I took a course when I was in college, I still remember,
0:55:48 it was Biosciences 169L, a neuroanatomy laboratory taught by Ben Reese.
0:55:54 He’s still there, I believe, and he was known then and I’m sure still now if he’s still
0:56:01 teaching as extremely challenging professor, extremely challenging, not as a person, not
0:56:08 as personality, but a ton of detail and rigor and high, high, high expectation for this laboratory
0:56:13 course in neuroanatomy, which involved lectures, it involved in a neuroanatomy textbook where
0:56:17 you’d look at essentially panels of different brain sections from different species, different
0:56:21 types of stains of different brain tissue, mind you, this is an undergraduate course,
0:56:25 and then there was a laboratory component, hence the L in 169L where you’d have to go
0:56:31 from microscope station to microscope station identifying structures based simply on what
0:56:37 you could see down the microscope and therefore you had to know what the stain was, what was
0:56:41 essentially visible to you on the slide because certain stains reveal certain things like
0:56:45 the, what we call the cell body of neurons versus the, the sort of wires, what we call
0:56:48 the axons between neurons, et cetera, et cetera.
0:56:51 I remember thinking this is a really hard course.
0:56:57 It was a very difficult course and my mode of studying for the course involved, of course,
0:57:03 going to class, doing the dissection, we dissected a sheep brain at that time, so we’re literally
0:57:08 dissecting an actual brain, we’re doing microscope work, we’re learning about it from the textbook
0:57:13 and from lecture and there was a ton of new nomenclature about rostral, caudal, dorsal,
0:57:20 ventral, all the stuff of neuroanatomy and then at some point I made the decision perhaps
0:57:28 on the basis of sheer overwhelm to study for neuroanatomy by laying down on my bed in my
0:57:35 studio apartment, I lived alone and closing my eyes and flying through the nervous system
0:57:42 from different entry points, through the ear, review my cochlear anatomy, through the eye,
0:57:47 review my retinal anatomy, through the dorsal surface of the brain, thinking about the sulcian
0:57:53 gyri and then the corpus callosum and then I, and I can still see it in my mind’s eye.
0:57:58 So my process of studying for neuroanatomy, yes, involved exposure to the material, but
0:58:06 it involved hours upon hours of thinking about the material within my own brain.
0:58:08 So it’s a little bit meta unto itself there.
0:58:15 As a consequence, I like to think, in fact, I believe with some confidence that I have
0:58:19 very high mastery of neuroanatomy in different species as well.
0:58:23 Now, that’s my particular area of expertise, I don’t think I’m any kind of savant with
0:58:27 respect to neuroanatomy, I just spent hours upon hours learning the material and then
0:58:30 reviewing the material within my mind.
0:58:35 So in other words, testing myself, here’s what I would do if I were moving down a trajectory
0:58:41 of a neural tract, for instance, between say the hippocampus and a neighboring structure
0:58:45 and I didn’t know what was next, I would then go look it up in the textbook and then I’d
0:58:49 go back to this, you know, mental exercise visualization type studying.
0:58:51 It really wasn’t studying is the point.
0:58:56 The point is that I was testing myself, I was trying to find the points in which I no
0:59:01 longer had the knowledge to move further through, in this case, my mental image of the brain,
0:59:03 but through the material.
0:59:05 And this is the key aspect of testing.
0:59:10 It’s not about just knowing how many things you get right, how many things you get wrong.
0:59:14 It’s about recognizing exactly what you know and don’t know.
0:59:19 And an important component of testing is running up against those things where you say, I can’t
0:59:23 remember, I don’t know what comes next or I’m certain that that structure is the fimbria
0:59:27 and then you go and you look and you go, it’s not the fimbria, but guess what, I’ll never
0:59:33 forget, for instance, the location of the habanula or what it looks like, a structure
0:59:36 which by the way, since these names are kind of esoteric, at that time, we didn’t know
0:59:37 what it does.
0:59:40 It turns out it’s involved in disappointment.
0:59:43 It’s key to the depression circuits or the circuits that underlie depression in some
0:59:44 individuals.
0:59:47 It is suppressed by viewing of morning sunlight.
0:59:49 We know that too.
0:59:53 And by getting too much artificial light exposure in the middle of the night, you enhance activity
0:59:55 of the habanula.
0:59:59 Beautiful work not done by my laboratory, but other laboratories demonstrates that.
1:00:03 So what I just did for you there was hopefully teach you a little something about neuroanatomy
1:00:08 and depression, but more importantly, to just illustrate that how you test yourself can
1:00:12 be highly individual to the ways in which you learn best.
1:00:16 Now that contradicts what I said earlier, which is that this notion that people have
1:00:20 different learning styles and some people are verbal learners and some people are auditory
1:00:26 learners and et cetera, doesn’t really hold up so well anymore, but which by the way is
1:00:30 not to say there isn’t any research to support it, it’s just that it’s heavily contradicted
1:00:33 by other research that contradicts that idea.
1:00:40 That your approach, your mode of best testing yourself on material for sake of offsetting
1:00:44 the forgetting process and for identifying where you have gaps in your knowledge or where
1:00:49 you thought you knew something, but you don’t or you knew something, but it’s wrong.
1:00:53 That can be accomplished through the approach that’s best for you, which in my case turned
1:00:56 out to be lying down and thinking about the material in my head.
1:01:01 And still to this day, when I read a paper, I try, I don’t always do this, but what I
1:01:05 try to do is then take a walk in my yard or outside and I try and think about the key
1:01:09 components of that paper and think about some of the grass that are especially important,
1:01:11 which is what I’m going to do now.
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1:02:27 Okay, so I like to think that we’re establishing that testing yourself or testing your students
1:02:34 or being tested by your teacher is the best way to offset forgetting.
1:02:38 Let’s look at the literature that actually supports that statement directly because in
1:02:43 the previous experiment I described, it was either study, study, study, study, study, study,
1:02:48 test or study, test, test, test and then later everybody takes a test at the same time.
1:02:54 A variance on that was done where they had one group of students study material, so this
1:02:58 is new material and when I say study, I mean they were exposed to the material for the
1:03:03 first time and I realized this is a little bit of a problem because we’re using the
1:03:08 word study when in fact I’m trying to make the point that testing yourself is studying.
1:03:13 So forgive me but this is the way it’s mapped out in these experiments and these papers
1:03:16 should you look them up in our show note captions.
1:03:21 One group is exposed to the material, what we’re called studying and then takes a test
1:03:23 immediately after.
1:03:26 They are told what they got right, what they got wrong on that test and what the correct
1:03:34 answers are and then sometime later after a delay, they take a test of the same material.
1:03:39 Another group studies that is they’re exposed to the material, then there’s a delay.
1:03:42 That delay could be days, it could be weeks.
1:03:46 This experiment has been done every which way it seems by now.
1:03:52 Then they’re tested and then there’s another delay and then they take a test at the same
1:03:54 time that group one did.
1:04:02 So again it’s study test, long delay test for group one or study delay test, delay test
1:04:03 for group two.
1:04:09 Remember the final test is taken at the same time by everybody or group three study that
1:04:14 is they’re exposed to the material, then a long, long, long delay, then a test and then
1:04:18 the ultimate test, the test that everybody takes at the same time.
1:04:21 Can you guess which group performed best?
1:04:24 The essence of this experiment, if you’re listening to this and it’s not clear in your
1:04:28 mind is you’re either exposed to the material and tested very soon after and then take a
1:04:35 test after a delay say a week or two weeks later or you’re exposed to the material, there’s
1:04:39 a delay of a few days, then you take a test and then another few days and then you take
1:04:44 a test so it’s more evenly spaced or if you were assigned to the third group you’d study
1:04:48 you’re not going to see the material or be tested on it until a day or two before the
1:04:52 big test, then you’re tested on it, you get your answers back and then you’re tested on
1:04:53 it again.
1:04:56 You could imagine that the last group might perform best because they’re re-exposed to
1:05:00 the material, they’re told what the correct answers are so they know what they got wrong,
1:05:04 they know what they got right and then the next day they’re taking the test again.
1:05:09 I would have thought that group would perform best but it turns out the opposite is true.
1:05:14 It’s pretty wild, the best performance comes from being exposed to material, what in this
1:05:19 experiment they’re called studying, so they read a passage or they learn some math material
1:05:24 or language material or music material or motor learning, then they take a test very
1:05:29 soon after, even same day or next day and then there’s a long delay and then they take
1:05:31 the test, that group performs best.
1:05:37 Put differently, test yourself very soon, if not the same day, certainly the next day
1:05:42 or so, very soon after being exposed to material for the first time.
1:05:46 As opposed to the last group which performs worst, they perform worst.
1:05:49 Being exposed to material, then there’s a long period of time, then you’re tested on
1:05:53 that material, you are told what you got right, what you got wrong and then the next day you
1:05:55 take a test again.
1:05:59 Even with overlapping questions to the test you took just the day before and that group
1:06:05 performs worst and the group that studied had a gap test, had a gap test, they performed
1:06:06 somewhere in the middle.
1:06:07 How does this tell us?
1:06:13 What it tells us is so important, vis-a-vis neuroplasticity, vis-a-vis best learning strategies.
1:06:19 This is something that goodness, I wish I had learned when I was in graduate school, when
1:06:24 I was an undergraduate, when I was in high school and elementary school, goodness, even
1:06:29 when I was in kindergarten, I wish I’d learned this.
1:06:33 Test yourself on the material that you were just exposed to very soon after your first
1:06:41 exposure to it, because that offsets the natural forgetting of new material that the brain
1:06:42 is exposed to.
1:06:50 This is absolutely the hallmark of all the impressive data about testing as a tool for
1:06:55 learning, testing oneself or your students or being tested if you’re the student, by
1:07:01 your teacher, as a tool not just for evaluating performance, for knowing what you know and
1:07:06 don’t know but for consolidating that information in your neural circuits.
1:07:11 When I say consolidating that information in your neural circuits, I realize it’s a mouthful.
1:07:18 What we know is that this business of putting the testing soon after exposure to new material
1:07:21 is about offsetting the forgetting of that material.
1:07:25 You might say, “Wait, if that’s true, how come studying the material and then waiting
1:07:28 and then taking two tests right back to back where you’re learning the material again during
1:07:31 the test, that should be the best performing group.”
1:07:37 Well, there seems to be something fundamentally different about first exposure to material
1:07:39 versus testing yourself on that material.
1:07:41 We don’t know exactly what that is.
1:07:47 There’s some interesting neural imaging data in humans that this has to do something with
1:07:49 this notion of familiarity with material.
1:07:50 This is very simple.
1:07:57 This is easy to understand even though it involves a little bit of memory, neuroscience, nomenclature.
1:08:02 Agility with something, recognizing it is not the same thing as having agility with
1:08:07 that thing, of having mastery of that thing, is not the same thing as having mastery of
1:08:11 the material, of having committed it to memory.
1:08:15 When you read something over and over and over, you see it over and over.
1:08:16 You hear it over and over.
1:08:17 You think about it over and over.
1:08:21 Of course, you’re reading it or you’re hearing about it and you think that you’re learning
1:08:26 the material, that your neural circuits are changing but it’s a pretty passive process
1:08:33 or even if it’s a difficult chapter to read or a difficult passage of music.
1:08:39 The difference is when you’re tested on material, something happens in your performance of or
1:08:44 recalling of, if it’s just cognitive or you’re writing it down or you’re told to play the
1:08:50 music or do the motor movement, something happens in the error, the getting wrong of
1:08:56 certain things that cues your nervous system to lock in the information that you have right.
1:09:00 To remember what you have wrong so that you then correct it, which is far and away different
1:09:06 than exposure and re-exposure and re-exposure.
1:09:09 It’s a prerequisite to learning that you need to see the material for the first time.
1:09:12 You can’t just start testing yourself on material that you’ve never been exposed to.
1:09:16 I suppose you could, but you’re going to get it, I would imagine, mostly wrong.
1:09:19 We’re all wrong.
1:09:26 This business of using testing very soon after first exposure to material as a tool to study
1:09:31 in order to offset forgetting is clearly tapping into this difference between familiarity with
1:09:38 something for which we know certain brain areas are activated versus recollection, being
1:09:43 able to take that material and bring it to memory, bring it to your focused attention
1:09:45 and use that material.
1:09:48 I realize this is a bit abstract and some of this is still being parsed.
1:09:52 If you’re interested in the neuroscience of familiarity with something versus your ability
1:09:58 to actually recall something and have mastery of that material, there’s a really nice review
1:10:01 that I provide a link to in the show note caption.
1:10:02 It’s published in the journal HIPAA Campus.
1:10:06 I always chuckle at the fact that there’s a journal that’s named after a brain structure.
1:10:11 After all, as far as I know, there isn’t a journal called Retina or Amygdala.
1:10:16 I have a brief anecdote from graduate school whereby I learned that there was this journal
1:10:22 HIPAA Campus and it was my first graduate student gathering in graduate school.
1:10:28 The guy who hosted it turns out it was a luminary in the field of learning and memory.
1:10:30 I was saying, “This is ridiculous.
1:10:31 There’s a journal called HIPAA Campus.
1:10:33 Here I’m a first-year graduate student.”
1:10:34 He goes, “Yeah, there is.”
1:10:36 I said, “Yeah, that’s so silly.
1:10:41 Who are the idiots that name a journal after a brain structure?”
1:10:44 Turns out there’s also a journal called Cerebral Cortex and there’s probably one about spinal
1:10:45 cortex.
1:10:47 It turns out I was the idiot saying this.
1:10:51 The guy I was talking to, who of course was the host of the party, said, “Yeah, actually,
1:10:52 that’s my journal.
1:10:53 I founded the journal HIPAA Campus.”
1:10:54 You can look them up.
1:10:59 At this point, you’re going to take a test and it’s a super easy test.
1:11:04 I realize we’re a bit into the material and we’re all probably fatiguing a little bit,
1:11:09 marveling, I hope, at what an incredible tool testing and in particular self-testing soon
1:11:12 after being exposed to new material is.
1:11:14 The question is this.
1:11:16 By the way, this is an open-ended question.
1:11:19 You’re not supposed to know the answer because I haven’t told you the answer yet, but I want
1:11:23 you to think about this.
1:11:31 If one looks at the majority of data in this whole field of testing as a studying tool,
1:11:36 how much improvement do you think you get from testing yourself once on new material?
1:11:41 Do you think it’s a 10% improvement, a 20% improvement?
1:11:45 Here I’m just comparing to testing yourself once on material that you were just exposed
1:11:49 to for the first time versus not testing yourself at all.
1:11:51 How much do you think you improve?
1:11:56 The answer is about 50%, five, zero.
1:12:02 I can say that on the basis of the fact that in studies of musical learning, of mathematical
1:12:06 learning, of language learning, of motor learning, when subjects are exposed to new material
1:12:12 and then tested at some period of time later, the percentage of information they get right
1:12:20 or that they are able to perform something correctly diminishes over time, especially
1:12:24 because they’re not doing any practice and no testing in the intervening time.
1:12:26 This was built into these experiments.
1:12:31 Then you simply ask how much of the material was forgotten if they just were exposed to
1:12:33 the material.
1:12:38 In the case of say music learning, your teacher sits down next to you and shows you the scales
1:12:44 on the piano, but then you’re not practicing them in between versus, or perhaps another
1:12:48 example would be somebody gives you a lecture about a particular phase in history and then
1:12:51 you’re not being exposed to the material again and you’re not self-testing versus if you
1:12:57 just take one test, even a self-directed test of the material immediately after irrespective
1:13:02 of how well you perform, you have the amount of forgetting.
1:13:07 I want you to think about self-testing in this way because we’re thinking about optimal
1:13:08 studying strategies.
1:13:12 You have the amount of forgetting that would normally occur.
1:13:13 This is so important.
1:13:18 In fact, I don’t even know that most neuroscientists think about learning a neuroplasticity this
1:13:19 way.
1:13:24 Most everybody, including neuroscientists, are taught, were taught, continue to be taught,
1:13:28 that you’re exposed to new material, you focus okay, then during sleep there’s remodeling
1:13:33 of the connections, all that’s true, but we really need to think about how most information
1:13:37 that comes into our nervous system each day is forgotten.
1:13:38 Most of it is completely discarded.
1:13:44 There are some rare clinical deficits where people remember everything and I’ll tell you,
1:13:46 these people really struggle in life.
1:13:49 They do not do well in work and relationships.
1:13:55 They remember every little detail of everything and it is incredibly disruptive to their quality
1:13:56 of life.
1:13:57 It’s nothing you want.
1:14:02 You want to have a great memory for the right things.
1:14:07 When you self-test material, you have the amount of forgetting that occurs compared
1:14:09 to if you’re just exposed to the material.
1:14:15 I want you to keep that fact in mind because that fact is the one that really hit me upside
1:14:21 the head and made me realize, goodness gracious, how I wish that I’d self-tested myself on
1:14:26 material that I wanted to remember over time rather than reading it over and over.
1:14:29 I had this elaborate process for studying that I use all through college and graduate
1:14:33 school and it worked pretty well for me where I’d read and highlight, then I’d write out
1:14:36 my notes, then I would write little paragraphs about that stuff.
1:14:40 Some of that probably mimicked self-testing, indeed it had to have, and then of course
1:14:43 I would take the quizzes and I would go to office hours.
1:14:46 Once I got serious about school, I got really serious about school and of course I still
1:14:47 forget things.
1:14:51 I’ve made errors on this podcast before, in part from going too fast or making a joke
1:14:55 that people didn’t perceive as a joke, the whole story there, but in any case, of course
1:14:56 I make errors.
1:15:00 Of course, I’ve forgotten certain things and sometimes I misspeak.
1:15:01 I always strive to get things accurately.
1:15:04 We correct things in the show note captions if they’re called out to us.
1:15:10 We’re now using AI to review the podcast and adjust anywhere using insertions or actually
1:15:15 replacing those words if we need to and so on and so forth, but yes, we all forget things.
1:15:22 We all make errors, but if I had just known that testing myself on material while walking
1:15:26 out of class or soon after getting home or later that evening or the next day would allow
1:15:33 me to perform so much better on an exam, a midterm or a final exam and of course I still
1:15:36 would have studied because I was committed and you should still study as much as you
1:15:40 feel is necessary to get mastery of the material for you.
1:15:46 However, if I had known that testing oneself or being tested soon after exposure to material
1:15:50 would have the amount of forgetting even out to a year later, I definitely would have
1:15:53 saved myself a lot of time.
1:15:57 Let’s talk about some specifics of ways that you can self test or if you’re a teacher or
1:16:01 if you have good dialogue with your teacher and they are open minded, perhaps they are
1:16:09 open to hearing about what are the best forms of testing oneself as a tool for learning.
1:16:18 The best tests are open-ended short answer, very minimal prompt tests, not unlike the
1:16:25 type that we’ve taken today during this podcast, as compared to multiple choice tests.
1:16:30 Multiple choice questions allow for familiarity of names, of facts.
1:16:37 It’s going to be A, B, C, D and sometimes E is A and C and so on and so forth and within
1:16:41 each of those A, B, C, D, E answers and you’re looking for the right answer, you’re looking
1:16:46 for the familiarity, the recognition of something, yes, this, not that, okay, that’s the best
1:16:49 answer you circle C, okay, this kind of thing.
1:16:52 As opposed to an open-ended question where you have to write out your answer, you have
1:16:55 to recall the information, right?
1:17:01 It requires a much greater degree of mastery of the information than does familiarity or
1:17:04 recognition of the material.
1:17:10 So the best tests as study tools are going to be open-ended short answer questions or
1:17:12 even long answer questions.
1:17:17 Now there’s one exception to this, which are multiple choice tests that include tricks,
1:17:18 okay?
1:17:24 If you’ve ever taken the GRE, the Graduate School Entrance Exam or the LSAT or the MCAT,
1:17:28 there are some questions in there that are very straightforward, but in those standardized
1:17:34 tests, they tend to include some quote unquote trick questions in which those questions don’t
1:17:39 allow you to just recognize the correct answer and distinguish it from the other incorrect
1:17:45 answers, but rather they have answers in there that on first blush look like the right answer
1:17:51 and people have a tendency to circle those and move on or to select those and move on.
1:17:55 But if you think about the material a little more deeply, turns out those quote unquote
1:17:59 obvious answers are actually the incorrect answers.
1:18:05 So there are versions of multiple choice tests where it requires a greater degree of mastery
1:18:09 of the material where simple familiarity won’t serve you and you actually have to be able
1:18:13 to recall the different components of information leading into that.
1:18:18 But those are a bit more rare, certainly in the context of other kinds of learning like
1:18:22 musical learning, although I suppose for music theory that could be relevant.
1:18:26 But when I say music learning, I’m just kind of defaulting to the idea of the mechanics
1:18:29 of musical learning, but of course there’s music theory, et cetera.
1:18:35 So what I’m effectively saying is the ultimate exam, the final exam, the midterm exam, the
1:18:39 exam that’s administered to you rarely do you have control over the format of that exam.
1:18:41 Sometimes it’s mixed format.
1:18:46 But the different ways in which you self-test as a form of study are really key.
1:18:49 And ideally you would make these open-ended.
1:18:53 In other words, you would not simply rely on multiple choice.
1:18:57 You would rely on a form of self-testing or that you give your students or that your teacher
1:19:02 gives you that requires you to think about the material with some degree of depth, with
1:19:05 some degree of effort, and of course you’re going to get certain things wrong.
1:19:10 Now I would hope that if testing is being used as a learning tool, as opposed to just
1:19:16 for evaluation, but here we’re talking about using testing as a learning tool, that it
1:19:21 wouldn’t impact, at least not at that moment, your final performance in the course or whatever
1:19:22 it is.
1:19:25 Rather it is testing for sake of learning.
1:19:30 Now we know from the literature that students don’t like pop quizzes.
1:19:33 I gave you a few today and forgive me.
1:19:34 We don’t like pop quizzes.
1:19:40 We know this in the form of the reduction in teaching evaluation scores.
1:19:45 Having received teaching evaluation scores of different, let’s say, values over the years
1:19:49 and I always take the feedback seriously.
1:19:53 One salient comment that just leapt into my mind was the fact that I end up mentioning
1:19:56 my Bulldog Costello too often in class.
1:19:59 So here I’m mentioning him again just to get back at that one student that said I mentioned
1:20:00 too much.
1:20:01 I mentioned him as much as I want.
1:20:07 The point here is that when students evaluate their teachers, they tend to punish their
1:20:09 teachers for pop quizzes.
1:20:11 Does that mean pop quizzes aren’t effective?
1:20:13 No, but you know what’s more effective?
1:20:17 Telling students at the outset of class or telling yourself at the outset of any kind
1:20:23 of learning expedition, because this isn’t just about the classroom, that you’re going
1:20:27 to take a bunch of exams, that you’re going to use testing or quizzes, whatever you want
1:20:34 to call them, as a form of teaching and learning, and that you can expect five tests or five
1:20:39 quizzes during the course of being presented the material or that you are going to test
1:20:41 yourself every day after the material.
1:20:43 Now, sometimes you have to go from one class to the next class.
1:20:47 There isn’t an opportunity to test yourself, but guess what’s not going to be helpful?
1:20:50 Walking out of class and getting immediately onto your phone, we know that that probably
1:20:55 inhibits your ability to remember the material because it’s going to enhance forgetting because
1:21:01 you do have this key opportunity right after being exposed to new material to help offset
1:21:05 the forgetting by testing yourself on that material as soon as possible after being exposed
1:21:06 to it.
1:21:13 So again, even though I did not attend school in an era where we had smartphones and texting,
1:21:20 I recall walking out of class and just walking out of class and going on my bicycle, but
1:21:23 of course there were people to talk to, there were other things to attend to.
1:21:27 If you’re really serious about learning material, take a few seconds, maybe even a few minutes
1:21:30 after being exposed to that material and think about that material.
1:21:34 Test yourself on it, and if you find that you don’t know the material, you’re confused
1:21:37 by it or overwhelmed by it, great.
1:21:41 You just accomplished the first step in queuing your nervous system to the fact that it needs
1:21:46 to learn that material and you’ve created an opportunity for enhanced neuroplasticity,
1:21:51 which is really what all of this stuff about testing as a form of studying is about.
1:21:55 You’re going to test yourself so that you figure out what you don’t know, so that you
1:22:01 then look up that material, test yourself on it again, so that ultimately you forget
1:22:03 very little of it, if any.
1:22:06 Now there are other components to learning a neuroplasticity that I’ve talked about on
1:22:10 previous podcasts that are just too interesting not to mention, but I’m just going to mention
1:22:13 them in brief, things like GAP effects.
1:22:17 GAP effects are so cool and they’ve been demonstrated for lots of different forms of learning.
1:22:24 GAP effects are what I just did, which is to take periodic pauses in the learning of
1:22:30 material as short as five to 10 seconds, but even as long as 30 seconds during which, guess
1:22:34 what, your hippocampus, the neurons in your hippocampus, repeat information that you’ve
1:22:42 been exposed to for the first time at a rate 20 to 30 times faster than typical, just as
1:22:44 it does during rapid-eyed movement sleep.
1:22:52 So if you are a teacher and/or if you are a learner periodically throughout an episode,
1:22:56 a class, or whatever, of trying to learn new motor skills or music skills or whatever kind
1:23:03 of learning, pause and let your hippocampus generate more repetitions of that material
1:23:06 than it would otherwise if you just tried to barrel through.
1:23:11 So I realize as we’ve gone through today’s discussion that words like test and quiz,
1:23:16 evaluation, offsetting, forgetting, all of that stuff can spike people’s cortisol.
1:23:22 It can give us flashbacks to uncomfortable classroom experiences related to being called
1:23:27 on, cold called for the answer, a vicious trick that instructors play.
1:23:32 Keep in mind that testing as a form of studying, whether or not self-directed or given to you
1:23:40 by a teacher is not for sake of evaluation at the level of, okay, you get an exam at
1:23:44 the end of a lecture and then you do your best to answer those questions and then you
1:23:47 turn it in and it impacts your grade.
1:23:54 No, this is about being told or revealing to yourself how much you know and don’t know,
1:23:57 and then of course being told the correct answers so that you can compare your answers
1:24:02 to the correct answers and doing this frequently and ideally very soon after being exposed to
1:24:03 the material.
1:24:08 That’s one of the key things that I keep coming back to again and again here because it’s
1:24:13 something that frankly was not done while I was in school for whatever reason.
1:24:18 I think that’s largely because when people hear the word testing, they think of evaluation
1:24:23 and if anything, at least in the United States over the last 30 years, but in particular
1:24:28 over the last 15 years, there’s been this tendency to shift away from formal evaluation.
1:24:33 I personally believe that one can learn in many different styles and many different contexts.
1:24:39 I, of course, as a university professor, believe that for certain topics, in particular science
1:24:44 and medicine and health, but other topics as well, of course, that formal rigorous coursework
1:24:50 is by far the best way to learn information for me, but that regardless of whether or
1:24:53 not you’re learning just from YouTube or you’re learning from podcasts or you’re learning
1:25:00 from books or you’re learning from the school of life as it were, from experience that testing
1:25:06 as a form of studying is absolutely key and gosh, there’s such a beautiful body of research.
1:25:10 In fact, I’ll link to several studies, including a review entitled “Testing Enhances Learning,
1:25:16 a Review of the Literature,” as well as a beautiful article, “Test Enhanced Learning,”
1:25:19 which gets into this and there’s a wonderful book about this that I’ll also provide a link
1:25:25 to in the show note captions, all, of course, authored by researchers who have worked squarely
1:25:30 in this field and compare the data on testing as a studying tool to other forms of studying
1:25:31 and learning.
1:25:37 So it’s a really impressive literature that I do believe we all should have known about,
1:25:39 and that’s why I’m passing it on to you now.
1:25:43 Now before we wrap up, I want to make sure that I emphasize some of the other key components
1:25:49 to studying and learning that have nothing to do with testing as a studying tool.
1:25:58 And those are the role of emotion, the role of story, and the role of what’s called interleaving.
1:26:04 Now in terms of emotion, I think we all inherently understand that more emotionally laden experiences
1:26:06 are remembered more durably.
1:26:07 We tend not to forget them.
1:26:12 In fact, this is the basis of things like PTSD, post-traumatic stress disorder.
1:26:18 It is the reality that one trial learning that is exposure to something and never forgetting
1:26:26 it occurs very readily when the thing that we’re exposed to is negative or has a very
1:26:28 heavy negative emotional salient.
1:26:31 So it could be something we read or something we see.
1:26:34 Sometimes it’s something that happens to us.
1:26:37 You know, I don’t like the idea of that, but this is true.
1:26:45 Your nervous system is wired such, neuroplasticity is such that stressful experiences, because
1:26:52 they deploy such massive amounts of adrenaline, epinephrine, as well as other neuromodulators
1:26:58 allow very quickly for the milieu, the environment of the neural circuits that led up to that
1:27:03 experience to strengthen their connections with one trial, so-called one trial learning.
1:27:11 This is why, sadly, although at the same time from an adaptive perspective, we say fortunately,
1:27:17 if you were to step outside today and, God forbid, see somebody hit by a car, you would
1:27:18 remember that.
1:27:20 Chances are you would remember that forever.
1:27:26 Now, that does not mean that the emotional components of that memory are necessarily
1:27:27 going to stay within you.
1:27:33 There are tools for the treatment of PTSD, such as the different ones that come to mind
1:27:41 are systematic exposure therapy, where you’re re-exposed to that idea or memory, sometimes
1:27:47 even circumstance, with, of course, the support of a trained professional, typically a psychiatrist
1:27:53 or psychologist, and the emotional load of that experience is gradually uncoupled from
1:27:55 your memory of the experience.
1:27:58 There’s things like EMDR, there are pharmacologic approaches.
1:28:00 Some of these are combined with the sorts of things I’ve described.
1:28:03 I’ve done entire episodes about stress and PTSD.
1:28:08 Again, you can find those at hubermanlab.com by putting stress PTSD into the search function.
1:28:16 However, we know that it is the same neuromodulators, mainly epinephrine and norepinephrine, deployed
1:28:20 at massive amounts in those moments where something very stressful happens that allows
1:28:25 the neural circuits that led up to the circumstance, as well as the neural circuits that encode
1:28:31 at that visual scene and scenes like it or sounds like it, to be locked in and linked
1:28:32 to the stress response.
1:28:38 Now, what this is really all saying is that negative stuff is remembered typically the
1:28:44 first time and every time, and very durably, over time.
1:28:48 As compared to positive experiences, which as far as peak experiences go, birth of your
1:28:55 first child, a wedding, a wonderful professional or personal experience, those two can be
1:29:01 one trial learning and memory, but most things that we are exposed to are not at those extremes,
1:29:03 either negative or positive.
1:29:11 However, we know that any kind of story, any kind of emotional emphasis on material, either
1:29:16 in the delivery of that material, but certainly in the way that that material is perceived
1:29:20 by you, like getting really excited about something you want to learn or thinking something
1:29:26 is really awful, is likely to be more readily and stably committed to your memory.
1:29:30 That’s because of these neuromodulators like epinephrine and norepinephrine, but other
1:29:34 neuromodulators as well, that wire those experiences into your neural circuits.
1:29:38 Again, these neuromodulators, epinephrine, norepinephrine, we also hear about acetylcholine,
1:29:45 dopamine, et cetera, they can operate at low levels and sort of background levels.
1:29:51 They can create subtle fluctuations in mood, focus and attention, or they can create massive
1:29:54 shifts in mood, focus and attention, depending on their levels, their timing and much, much
1:29:55 more.
1:30:01 The point here is that if you’re a teacher and/or if you are a learner, paying attention
1:30:05 to your internal state as you’re trying to learn is very key.
1:30:09 We’ve all had that teacher, that lecture that just kind of drones things out in monotone.
1:30:14 If you need to learn the material coming out of a source like that, person or otherwise,
1:30:18 you’re going to have to ramp up your level of internal attention consciously in order
1:30:24 to bring about some emotional salience, some intensity to the way it’s perceived.
1:30:29 You can do that just through your own thinking, as opposed to the situation where you have
1:30:33 a super dynamic teacher who’s telling you things with wide eyes and perhaps even cracking
1:30:34 jokes.
1:30:38 By the way, the teachers that crack jokes get lower teacher evaluations than those that
1:30:39 don’t crack jokes or swear.
1:30:40 Did you know that?
1:30:44 The teachers that crack jokes and swear, they’re perceived as more likable, but they get lower
1:30:46 overall evaluations typically.
1:30:51 They’re seen as less professional and therefore less good teachers by their students.
1:30:56 So I try not to make too many jokes or swear in my lectures.
1:31:02 The point being that we all have those really wonderful dynamic teachers, yes, it’s much
1:31:04 easier to learn and remember that material.
1:31:08 You still need to test yourself on it, but it’s much easier to learn that material for
1:31:10 the very reasons I say it before.
1:31:15 It’s a lesser example of more deployment of the neuromodulators in you, the learner that
1:31:18 is exposed to that material.
1:31:23 So emotion matters, so much so that in a beautiful review about learning a memory from the great
1:31:28 James McGaw, one of the luminaries in modern neuroscience and psychology of memory, he
1:31:35 talked about a medieval practice, this is pretty wild, whereby people and kids, kids
1:31:41 are people of course, but adults and kids were taught information and then thrown, literally
1:31:43 thrown into cold water.
1:31:44 Why?
1:31:48 To deploy adrenaline and consolidate memory of the material they were exposed to.
1:31:53 Now I know we’ve covered deliberate cold exposure on this podcast before, no, I’m not
1:31:57 saying you need to do a cold plunge after being exposed to new material, but guess what?
1:32:02 They were doing that many hundreds of years ago and it makes sense logically based on
1:32:08 all our understanding of the neurobiology underlying things like PTSD, underlying emotion
1:32:14 laden memory formation and consolidation and our ability to remember things that were emotionally
1:32:17 laden, much better than things that were less emotionally laden.
1:32:22 So if you want to take a cold shower after learning some material or even better, testing
1:32:27 yourself mentally on that material while in a cold shower or cold plunge, you certainly
1:32:28 can.
1:32:30 Just don’t stay in there too long.
1:32:33 These best practices, if you want to know what those best practices are for deliberate
1:32:37 cold exposure, you can check out our deliberate cold exposure newsletter at hubermanlab.com.
1:32:38 It’s completely zero cost.
1:32:40 You don’t even need to sign up.
1:32:44 You simply go to newsletter in the menu tab and you can find that PDF.
1:32:48 And now because you are becoming proficient in an understanding of neuroplasticity and
1:32:52 learning and testing and neuromodulators like epinephrine, yes, drinking caffeine will increase
1:32:55 your levels of epinephrine.
1:32:59 Not strikingly so, but enough that it probably helps you learn things a little bit better.
1:33:01 Did you drink the coffee after?
1:33:04 Listen, that’s getting a little bit too down in the details.
1:33:09 The most important components to learning are that you be alert so that you can attend,
1:33:13 so you can pay attention to the material you’re trying to learn and then testing yourself later.
1:33:18 And of course, the other component, which is getting sufficient amounts of great sleep
1:33:19 each night.
1:33:22 And I highly recommend doing NSDR.
1:33:24 I mentioned GapFX before.
1:33:25 Those are very, very cool.
1:33:28 I just used another one now.
1:33:33 And the final tool for studying that I believe is not discussed enough and is a bit counterintuitive,
1:33:38 so it’s a fun one to just mention and that perhaps you can explore in your own studying
1:33:41 and learning adventures is interleaving of information.
1:33:44 This one’s kind of wild actually.
1:33:51 Turns out that if your instructor or you takes information about something that they’re trying
1:33:55 to teach you or you’re trying to learn, maybe it’s piano, maybe it’s neuroscience, maybe
1:33:57 it’s how to learn better.
1:34:02 And every once in a while throws in a little anecdote about something, let’s just say.
1:34:09 Or mention something about the Olympics or incorporate something that seems pseudo-random
1:34:13 because it’s not actually related to the material you’re trying to learn.
1:34:18 Turns out that that acts not as a gap in the same sense that GapFX, which are times in
1:34:23 which you do nothing in order to get more repetitions of the material you just heard
1:34:25 in your hippocampus.
1:34:30 But rather those breaks of interleaving information, not just getting a steady barrage like drinking
1:34:34 from a fire hose of new information from start to finish.
1:34:42 Turn out to enhance overall learning ability probably we think at a mechanistic level because
1:34:46 the neural circuits are able to generate more repetition similar to GapFX.
1:34:53 But actually in a very interesting way also because by injecting other information that
1:34:58 seems totally unrelated, random or pseudo-random.
1:35:03 It allows the brain areas that are responsible for encoding information to take whatever new
1:35:08 information you’re learning and to incorporate it with existing knowledge or even distantly
1:35:09 related knowledge.
1:35:12 So does this mean that you should learn math and history in the same lecture?
1:35:16 Well, I think that might be a bit overwhelming kind of like drinking from two fire hoses.
1:35:22 Here we’re talking about interleaving challenging information that’s new to you with little
1:35:26 anecdotes, little bits of information that perhaps are new to you but don’t require a
1:35:27 lot of challenge.
1:35:31 Which is of course why every once in a while I throw in a little anecdote about my bulldog
1:35:34 or learning neuroanatomy or something of that sort.
1:35:39 It’s not just to provide a break, it’s to provide examples that are related but not central
1:35:43 to the material that we’ve been talking about today, which is all about how to study and
1:35:45 learn optimally.
1:35:51 Okay, so I realize that many of you are not students any longer although some of you are.
1:35:53 But in many ways we are all students.
1:35:57 We are all constantly being exposed to all sorts of information out in the world and
1:36:01 goodness knows, thank goodness we don’t remember it all.
1:36:05 But there is of course information that we would like to remember, that we would really
1:36:10 like to consolidate in our memory and be able to have some mastery over.
1:36:14 Earlier I said I would distinguish between unskilled, skilled mastery and virtuosity
1:36:15 and I’ll do that now.
1:36:21 Unskilled of course means that we have limited understanding, let alone ability to use information,
1:36:26 skilled typically means we know and can recognize and use information in basic ways or even
1:36:28 advanced ways.
1:36:32 Mastery typically means that we have close to the full depth of knowledge in a given
1:36:35 area and that we can use it pretty flexibly.
1:36:41 And virtuosity, at least my definition of virtuosity is where we actually have such mastery of
1:36:48 material that we can use it in ways that we still don’t even know how we can use, meaning
1:36:54 that we can inject elements or we even invite elements of uncertainty and kind of spontaneity
1:36:55 into the use of that material.
1:36:59 Here I’m thinking of great musicians, I’m thinking of great athletes where they know
1:37:02 all the plays, they know all the moves, it’s all scripted into their nervous system and
1:37:05 they can deploy those at any time so they have real mastery.
1:37:13 But in order to display their incredible abilities, their virtuosity, they actively invite in
1:37:18 the X factor, the uncertainty such that sometimes they find themselves playing their instrument
1:37:23 or singing or performing athletically or mathematically or what have you in ways that
1:37:26 even surprise them.
1:37:31 And that of course is a lot to expect of ourselves, I think most of us would be content
1:37:37 to have skill and mastery of the things that we care about and should we achieve virtuosity,
1:37:38 then wonderful.
1:37:43 But one of the main points of today’s discussion was to arm you with an understanding of neuroplasticity
1:37:48 in the context of studying and learning to really understand that so much of learning
1:37:54 stably and consolidating information over time is to offset the forgetting process.
1:37:59 And that testing is not just a tool for evaluating our knowledge but rather a tool for evaluating
1:38:02 and reinforcing and building our knowledge.
1:38:08 Put differently that testing is an excellent tool if not the best tool for studying.
1:38:12 And I think that’s an important reframe that others have brought about and that I really
1:38:17 want to highlight, underline and boldface during today’s discussion.
1:38:21 It’s one that I certainly wish I had applied more in my educational trajectory and it’s
1:38:28 one that I plan to deploy further in my seeking out of new knowledge in terms of the podcast
1:38:32 and neuroscience but in other areas of my life as well because from the existing literature
1:38:38 and hopefully from the way it was presented to you today, you probably realize that it
1:38:45 is near infinite if not infinite that we can apply testing as a tool for studying, self-testing,
1:38:49 testing of others, using testing as a way to really probe what we know and don’t know
1:38:52 and to really offset that forgetting process.
1:38:58 And in that sense, it is really nicely aligned with what we know about neuroplasticity and
1:39:03 it’s also something that we can use freely and that you can use covertly, that you can
1:39:10 apply in your own seeking out of knowledge and new skills of all kinds classroom or otherwise.
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1:39:44 For those of you that haven’t heard, I have a new book coming out.
1:39:46 It’s my very first book.
1:39:50 It’s entitled Protocols and Operating Manual for the Human Body.
1:39:52 This is a book that I’ve been working on for more than five years and that’s based
1:39:58 on more than 30 years of research and experience and it covers protocols for everything from
1:40:04 sleep to exercise to stress control protocols related to focus and motivation.
1:40:09 And of course, I provide the scientific substantiation for the protocols that are included.
1:40:13 The book is now available by presale@protocallsbook.com.
1:40:15 There you can find links to various vendors.
1:40:17 You can pick the one that you like best.
1:40:22 Again, the book is called Protocols and Operating Manual for the Human Body.
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1:40:48 If you haven’t already subscribed to our neural network newsletter, our neural network
1:40:53 newsletter is a zero cost monthly newsletter that has protocols which are one to three
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1:41:00 deliberate cold exposure.
1:41:04 We have a foundational fitness protocol that describes resistance training, sets and reps
1:41:08 and all of that as well as cardiovascular training that’s supported by the scientific
1:41:12 research and we have protocols related to neuroplasticity and learning.
1:41:16 Again, you can find all that at completely zero cost by going to HubermanLab.com, go
1:41:21 to the menu tab in the right corner, scroll down to newsletter, you’re putting your email
1:41:24 and we do not share your email with anybody.
1:41:29 Thank you once again for joining me for today’s discussion all about how to study and learn
1:41:33 and last but certainly not least, thank you for your interest in science.
1:41:38 [Music]