How to Change Your Brain & Increase Neuroplasticity at Any Age

00:00:00.000 | - As we get into adulthood,

00:00:04.120 | most of our neural maps in the brain,

00:00:05.900 | certainly our sensory maps and our cortex,

00:00:07.840 | our motor maps that allow us to move in particular ways,

00:00:11.700 | those have been established.

00:00:13.120 | You can still change them,

00:00:14.760 | but they've mostly been established

00:00:16.480 | throughout childhood and into our early 20s.

00:00:18.600 | And if we want to modify those circuits with neuroplasticity,

00:00:21.580 | there are a couple of key requirements.

00:00:22.900 | One, you need to be alert.

00:00:24.740 | You can't get neuroplasticity.

00:00:26.200 | That is, you can't trigger neuroplasticity

00:00:28.640 | unless you're alert.

00:00:29.600 | You also have to be focused.

00:00:31.060 | This is critical and differentiates adult plasticity

00:00:33.780 | in a major way from plasticity when we're young,

00:00:36.100 | where we can learn by passive exposure, okay?

00:00:39.320 | When we're young, we can learn by passive exposure

00:00:41.120 | or even better by focused exposure.

00:00:43.780 | But when we are adults,

00:00:44.880 | we need alertness and we need focus.

00:00:47.260 | Just passively being exposed to music or to motor pattern

00:00:52.380 | is not going to allow us to change our nervous system.

00:00:54.440 | That's been shown over and over again.

00:00:56.080 | Fortunately, what also has been shown over and over again

00:00:59.200 | is that if we are alert and we're focused

00:01:01.620 | and we are determined,

00:01:02.720 | especially if we undertake what's called incremental learning,

00:01:05.120 | where we go after small bits of neuroplasticity

00:01:08.920 | repeatedly over time,

00:01:10.540 | we can get as much neuroplasticity

00:01:12.680 | as one observes in childhood.

00:01:14.540 | It just takes longer and you have to do it

00:01:16.380 | so-called incrementally.

00:01:17.680 | There's a lot to say about that,

00:01:20.440 | but for sake of today's discussion about the vagus nerve,

00:01:23.260 | I just want to tell you that there's a particular pathway

00:01:26.680 | in the brain that involves the molecule acetylcholine.

00:01:30.600 | Acetylcholine is used to contract the muscles.

00:01:33.480 | It's released from motor neurons in the spinal cord onto muscles

00:01:36.520 | to contract the muscles.

00:01:37.700 | It's also used in the brain and elsewhere in the nervous system,

00:01:40.500 | and it does a lot of different things.

00:01:41.880 | It's actually involved in generating the rhythms of the heart,

00:01:45.020 | but acetylcholine released from a particular nucleus

00:01:48.360 | in the brain called nucleus basalis.

00:01:50.760 | The acetylcholine released from nucleus basalis

00:01:53.620 | is what we call permissive for plasticity.

00:01:56.520 | In other words, if you have acetylcholine released

00:01:58.920 | from nucleus basalis into the brain,

00:02:01.180 | plasticity is much more likely to occur.

00:02:04.140 | And in fact, acetylcholine released from nucleus basalis

00:02:07.900 | is sort of like a gate whereby if you release acetylcholine,

00:02:11.360 | the opportunity for neuroplasticity and learning

00:02:14.040 | is available for some period of time.

00:02:16.160 | So the question therefore becomes,

00:02:17.580 | how do you get acetylcholine released from nucleus basalis?

00:02:20.320 | There are these incredible experiments

00:02:21.740 | that have been done by Mike Merzenich and colleagues

00:02:24.680 | showing that if you stimulate nucleus basalis

00:02:26.920 | to release acetylcholine and you expose an animal or a human

00:02:30.100 | to a particular sensory stimulus,

00:02:31.740 | the brain remaps very fast according to that experience,

00:02:35.460 | just enormous amounts of plasticity

00:02:37.260 | that you wouldn't observe otherwise.

00:02:39.080 | There are also fortunately experiments showing

00:02:41.480 | that if you pharmacologically increase acetylcholine,

00:02:44.880 | that you can enhance the opportunity for neuroplasticity.

00:02:47.760 | You still need to do the learning.

00:02:49.540 | You still need to attempt to learn something.

00:02:51.020 | You still have to make it incremental,

00:02:52.720 | but the amount of plasticity is significantly increased

00:02:56.100 | when there's acetylcholine released from nucleus basalis.

00:02:59.360 | So in the absence of deep brain stimulation using an electrode,

00:03:02.860 | which most of you fortunately will not experience

00:03:05.500 | because it requires drilling down through the skull

00:03:07.440 | and placing an electrode in basalis,

00:03:08.960 | and assuming that you're not taking anything

00:03:12.060 | to increase acetylcholine transmission to learn,

00:03:14.400 | although there are ways to do that,

00:03:15.860 | I've talked about that before,

00:03:17.420 | and I'll talk about that again in a future podcast.

00:03:19.640 | Some of those ways include supplementing with things

00:03:22.080 | like alpha GPC, which is a precursor to acetylcholine.

00:03:25.780 | There are some other precursors to acetylcholine

00:03:27.740 | or things that stimulate the release of acetylcholine,

00:03:30.000 | such as huperzine and things like that,

00:03:32.020 | that will open the opportunity for enhanced plasticity

00:03:34.680 | for a few hours.

00:03:36.040 | And there is good old nicotine.

00:03:39.200 | I know the word nicotine brings to mind things like lung cancer,

00:03:43.020 | because for many, many years, many, many people,

00:03:45.580 | and still now smoked nicotine in the form of cigarettes,

00:03:48.260 | or vaping, both of which I think are absolutely terrible,

00:03:50.580 | as is dipping and snuffing,

00:03:51.940 | because yes, they increase levels

00:03:54.380 | of nicotinic acetylcholine receptor activation,

00:03:57.300 | which is just fancy nerd speak

00:03:59.140 | for acetylcholine transmission in the brain

00:04:01.340 | is enhanced by nicotine,

00:04:02.960 | but those delivery mechanisms also, of course,

00:04:05.660 | can give you cancer in the case of smoking,

00:04:07.640 | dipping or snuffing,

00:04:08.940 | and vaping, despite what you hear out there,

00:04:11.140 | is absolutely terrible for your health.

00:04:13.840 | I don't care what anybody says,

00:04:15.040 | the evidence is starting to really pile up

00:04:17.460 | that vaping is bad for you.

00:04:18.840 | Now, is oral form nicotine bad for you

00:04:22.340 | in the form of gum or in the form of a pouch, etc.?

00:04:25.140 | I just want to say a couple of things.

00:04:26.620 | One, it's extremely habit-forming.

00:04:29.220 | Two, it increases blood pressure,

00:04:32.420 | and it's a vasoconstrictor.

00:04:34.280 | These drawbacks about nicotine are real

00:04:36.780 | and are critical to consider

00:04:38.540 | if you're going to use nicotine as a focusing agent

00:04:40.760 | or a so-called nootropic.

00:04:42.500 | I don't really like that word,

00:04:43.680 | but if you're using nicotine as a way

00:04:46.000 | to enhance cognition and enhance neuroplasticity,

00:04:49.860 | you should know what the potential drawbacks are,

00:04:52.080 | most notably the habit-forming and addicting properties,

00:04:55.080 | which are very robust.

00:04:56.480 | Now, with that said,

00:04:57.720 | there are ways to non-pharmacologically stimulate

00:05:00.380 | the nucleus basalis acetylcholine pathway

00:05:03.020 | to enhance the window for plasticity.

00:05:05.180 | And the way to do that is,

00:05:06.840 | you guessed it,

00:05:07.740 | through the vagus nerve.

00:05:09.080 | Studies in healthy humans and humans

00:05:11.500 | who have had, for instance, stroke,

00:05:12.920 | as well as animal studies have shown

00:05:14.960 | that if you stimulate the vagus nerve electrically,

00:05:17.360 | you increase the level of alertness in the brain,

00:05:20.240 | and part of the mechanism by which you do that

00:05:22.360 | is the one I told you about a few minutes ago,

00:05:23.980 | the adrenals, vagus, locus coeruleus,

00:05:26.860 | but also there's a separate pathway

00:05:29.060 | from the NTS to nucleus basalis

00:05:31.760 | that stimulates the release of acetylcholine

00:05:34.080 | from nucleus basalis

00:05:35.260 | and opens up the opportunity for neuroplasticity.

00:05:38.380 | This, I should mention, is not a small effect.

00:05:42.100 | It is a rapid effect,

00:05:44.640 | and it's one that has allowed stroke patients, for instance,

00:05:47.340 | to improve their motor capabilities very quickly

00:05:50.200 | as compared to when the vagus nerve is not stimulated

00:05:53.240 | or when acetylcholine transmission

00:05:55.160 | is not enhanced pharmacologically.

00:05:57.160 | And fortunately, now, there are studies

00:05:59.360 | starting to accumulate in animal models

00:06:01.420 | and some in humans.

00:06:02.800 | We need more, but there are some showing

00:06:05.380 | that if you enhance alertness

00:06:07.520 | by way of activating the vagus nerve

00:06:09.920 | through the mechanism that I told you before,

00:06:12.180 | which is good old-fashioned high-intensity exercise,

00:06:14.960 | that in the several hours following that exercise,

00:06:18.240 | there is an enhanced opportunity for neuroplasticity.

00:06:21.860 | Now, that enhanced opportunity for neuroplasticity

00:06:24.760 | comes by way of two different pathways.

00:06:26.980 | You already heard about the first one,

00:06:28.420 | which is the locus coeruleus release of norepinephrine.

00:06:31.340 | That's going to increase alertness,

00:06:33.280 | which is a prerequisite for focus.

00:06:35.380 | And it appears to be the case

00:06:37.140 | that the release of acetylcholine from nucleus basalis

00:06:39.800 | that's also triggered by this high-intensity exercise

00:06:43.100 | is what allows for that alertness to be converted into focus.

00:06:48.180 | And those two things together,

00:06:49.380 | alertness and focus,

00:06:50.540 | are the triggers for adult neuroplasticity.

00:06:53.520 | If you think about this,

00:06:54.640 | this is really exciting.

00:06:55.840 | For 25 years or more,

00:06:57.640 | we've known that plasticity is possible in the adult human.

00:07:00.700 | We knew you needed alertness and you needed focus.

00:07:03.360 | We also, by the way,

00:07:04.520 | know that you need to get great sleep that night

00:07:07.480 | and in subsequent nights

00:07:08.800 | in order to actually allow the plasticity to occur.

00:07:11.400 | Plasticity is a process.

00:07:13.120 | It's not just triggered

00:07:13.960 | when you go about trying to learn something.

00:07:15.720 | It actually takes place in sleep,

00:07:17.820 | as well as sleep-like states

00:07:19.640 | like non-sleep deep rest and meditation,

00:07:21.560 | but especially in deep sleep

00:07:23.680 | and rapid eye movement sleep.

00:07:24.920 | This is why you can attempt

00:07:26.060 | to learn something cognitively or behaviorally

00:07:28.100 | over and over and over.

00:07:29.760 | You can't get those scales on the piano right.

00:07:31.700 | You can't get the, you know,

00:07:33.500 | the information dialed in from your class,

00:07:36.220 | a language class or from engineering

00:07:38.280 | or you're trying to figure out

00:07:40.040 | what this picture should be in your mind

00:07:41.780 | that you're going to paint, et cetera.

00:07:42.900 | You work at it, you work at it, you work at it,

00:07:45.800 | you sleep, you sleep,

00:07:46.700 | and then one day you wake up

00:07:47.700 | and suddenly you have the skill.

00:07:48.860 | It's because the actual rewiring of those circuits

00:07:51.660 | that we call neuroplasticity occurs during sleep,

00:07:53.900 | but it's triggered in those moments

00:07:55.780 | of incremental learning and really struggling.

00:07:58.200 | And keep in mind the struggle to learn something,

00:08:00.360 | that friction is part of the neuroplasticity process.

00:08:03.660 | And it's oh so clear now that alertness and focus

00:08:08.300 | are the prerequisites for plasticity,

00:08:10.300 | that alertness is coming in large part

00:08:13.140 | by way of the release of norepinephrine

00:08:14.700 | from locus coeruleus,

00:08:16.000 | that the focus is being augmented

00:08:18.060 | and perhaps it's even originating entirely

00:08:21.000 | from the release of acetylcholine and nucleus basalis

00:08:23.500 | that acts as sort of a spotlight

00:08:25.060 | on a particular set of things that are happening

00:08:27.100 | while we're trying to learn.

00:08:28.900 | and then that triggers the plasticity process,

00:08:31.540 | which takes place during sleep.

00:08:33.580 | So that beautiful picture

00:08:35.880 | of self-directed adaptive plasticity in adulthood

00:08:38.600 | is allowed to happen

00:08:41.580 | because the vagus nerve in part

00:08:44.840 | is triggering NTS to say,

00:08:48.400 | hey, locus coeruleus, nucleus basalis,

00:08:50.900 | wake up, release norepinephrine,

00:08:52.780 | release acetylcholine,

00:08:54.540 | now's the time to learn.

00:08:55.680 | So what this means is if you're struggling to learn,

00:08:58.700 | if you want to continue to have robust neuroplasticity,

00:09:01.640 | if you happen to have some damage to motor pathways

00:09:04.780 | or you're having trouble with focusing and brain fog,

00:09:07.220 | keep in mind, focus itself is served by a circuit

00:09:10.980 | that is subject to plasticity.

00:09:12.560 | You can actually get better at focusing

00:09:14.260 | by working on focus just the same way you would on any skill.

00:09:18.100 | And so if you're struggling with focus,

00:09:20.520 | I highly recommend finding a threshold of exercise

00:09:23.100 | that stimulates brain alertness,

00:09:25.340 | that triggers these pathways

00:09:27.220 | that are now starting to be clear

00:09:29.000 | that they occur from the literature in animals and humans.

00:09:32.320 | And yes, you might augment this

00:09:34.800 | with something like caffeine,

00:09:36.100 | which will further increase levels of norepinephrine.

00:09:38.900 | You might even use low dose nicotine.

00:09:40.720 | I'm not necessarily recommending that,

00:09:42.220 | certainly not for young people.

00:09:43.440 | And you do need to be aware of the habit forming,

00:09:46.300 | AKA addictive properties of nicotine.

00:09:48.140 | You definitely don't want to consume it in any form

00:09:50.320 | that's going to cause you to increase your risk of cancer

00:09:53.260 | or popcorn lung from vaping.

00:09:54.880 | You could use pharmacology.

00:09:56.620 | You could use alpha GPC.

00:09:57.960 | You could use herpruzine in combination with exercise.

00:10:01.160 | However, I strongly, strongly recommend

00:10:04.180 | that anyone who's interested in lifelong learning,

00:10:07.200 | think about organizing your bouts of learning,

00:10:09.060 | especially cognitive learning,

00:10:10.200 | to come in the two to three hours,

00:10:12.820 | maybe even four hours,

00:10:13.900 | but certainly in the one to two hours

00:10:15.420 | after you do some sort of exercise

00:10:17.280 | that doesn't leave you exhausted,

00:10:18.880 | but leaves you with elevated levels of energy in your body.

00:10:22.880 | So you don't want to take this physical exercise

00:10:25.460 | that I'm talking about to exhaustion

00:10:27.200 | because that's going to leave you depleted.

00:10:29.040 | That's going to cause a, you know,

00:10:30.680 | uptick in parasympathetic activity.

00:10:32.760 | Any of you that have done a hard leg workout,

00:10:35.040 | and then, you know, two, three hours later,

00:10:36.780 | you're just like, it's very clear.

00:10:38.400 | Brain oxygen levels are down,

00:10:40.080 | parasympathetic activity is up.

00:10:42.040 | You are tired because you exhausted

00:10:43.520 | all that energy and exercise.

00:10:44.840 | But if you can use exercise as a trigger

00:10:47.360 | to release adrenaline and stimulate these pathways

00:10:50.060 | within the brain that arrive via the signaling

00:10:52.540 | from the vagus,

00:10:53.300 | you do indeed open up the opportunity

00:10:55.560 | for enhanced neuroplasticity at any age.

00:10:58.860 | So,

How to Change Your Brain & Increase Neuroplasticity at Any Age | Dr. Andrew Huberman

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