Dr. Lisa Feldman Barrett

Yeah, okay. So if I were imaging your brain right now, what I would see is I would see changes in the signal that is related to neural activity in your visual cortex, even though there is no apple in front of you. And I would see a change in activity in your auditory cortex, even though you didn't really hear the crunch.

Yeah, okay. So if I were imaging your brain right now, what I would see is I would see changes in the signal that is related to neural activity in your visual cortex, even though there is no apple in front of you. And I would see a change in activity in your auditory cortex, even though you didn't really hear the crunch.

And your mouth is watering. And in fact, every time you sit down for a meal, your brain directs your saliva glands to produce more saliva to prepare you to eat and digest the food. So that usually happens in advance of even sitting down to a meal. That is all prediction.

And your mouth is watering. And in fact, every time you sit down for a meal, your brain directs your saliva glands to produce more saliva to prepare you to eat and digest the food. So that usually happens in advance of even sitting down to a meal. That is all prediction.

That's all of that is your brain preparing itself for what's coming because predicting and correcting is a much more efficient way to run a nervous system, really any system, than reacting to the world. Here's another example. Do you drink coffee?

That's all of that is your brain preparing itself for what's coming because predicting and correcting is a much more efficient way to run a nervous system, really any system, than reacting to the world. Here's another example. Do you drink coffee?

Okay. Do you drink coffee every day at the same time?

Okay. Do you drink coffee every day at the same time?

And are you one of these people that if you miss having coffee at that time, you get a headache?

And are you one of these people that if you miss having coffee at that time, you get a headache?

Well, I used to be a person who drank a lot of coffee. And I love coffee, but I don't drink it anymore. But I loved it, and I drank it always at the same time every day. And if I didn't drink it, I would get, at that time of day, I would get a massive headache.

Well, I used to be a person who drank a lot of coffee. And I love coffee, but I don't drink it anymore. But I loved it, and I drank it always at the same time every day. And if I didn't drink it, I would get, at that time of day, I would get a massive headache.

And the reason why, and this is true of every medicine you take, anything which affects your physiology, if you do it on a regular basis, your brain will come to expect it. And what that means, come to expect it, is that coffee has chemicals in it that will constrict your blood vessels everywhere. But in the brain, the brain is attempting to keep the blood flow pretty constant and even.

And the reason why, and this is true of every medicine you take, anything which affects your physiology, if you do it on a regular basis, your brain will come to expect it. And what that means, come to expect it, is that coffee has chemicals in it that will constrict your blood vessels everywhere. But in the brain, the brain is attempting to keep the blood flow pretty constant and even.

And so if every day at 8 o'clock in the morning you're drinking something that's going to constrict your blood vessels, then at 7.55 approximately, I don't know the exact timing, but a little bit before 8, your brain will dilate the blood vessels. Right. In preparation for that constriction so they remain constant.

And so if every day at 8 o'clock in the morning you're drinking something that's going to constrict your blood vessels, then at 7.55 approximately, I don't know the exact timing, but a little bit before 8, your brain will dilate the blood vessels. Right. In preparation for that constriction so they remain constant.

And if you don't drink that substance, then you have this big dilation and you get a very, very bad headache.

And if you don't drink that substance, then you have this big dilation and you get a very, very bad headache.

Yeah, sure. That's an example. Here's another example. Exercise. Okay. If you want to play tennis better, if you want to run a faster mile, what do you do? Train. Train. And you do the same thing over and over and over and over again. And you get better and faster and you burn fewer calories. You get more efficient. Why? Because your brain's predicting really well. That's what muscle memory is.

Yeah, sure. That's an example. Here's another example. Exercise. Okay. If you want to play tennis better, if you want to run a faster mile, what do you do? Train. Train. And you do the same thing over and over and over and over again. And you get better and faster and you burn fewer calories. You get more efficient. Why? Because your brain's predicting really well. That's what muscle memory is.