Caroline Leaf on Science of Thought at TEDxOaksChristianSchool (Transcript)

Here is the full transcript of author and cognitive neuroscientist Caroline Leaf’s TEDx Talk presentation on Science of Thought at TEDxOaksChristianSchool conference. To learn more about the speaker, read the full bio here.


Caroline Leaf on Science of Thought at TEDxOaksChristianSchool – Slides


Book(s) by the speaker:

Switch On Your Brain: The Key to Peak Happiness, Thinking, and Health

Think and Eat Yourself Smart: A Neuroscientific Approach to a Sharper Mind and Healthier Life

Who Switched Off My Brain? Controlling Toxic Thoughts and Emotions


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Caroline Leaf – Author and cognitive neuroscientist

Good morning everyone. How amazing that TED is in a school; I just think that’s just so exciting.

Well, I teach people about the brain, and 30 years ago, I asked a ridiculous question. And it really was a ridiculous question. This is the question: can the mind change the brain?

Now that was a ridiculous question, because the view at that time, and the scientists that trained me and my lecturers, we were told that the brain could not change. So if it was damaged, well that’s it; you just basically had to teach your patients to compensate for these things and to kind of get around the problem. But that seemed such a negative thing.

So I asked that question: Can a brain that’s damaged, can it not change, can it not grow? And a brain that’s not damaged, can’t we make that better? Can’t we increase our intelligence?

And so I decided to embark on a journey of researching and studying this and applying it in my practice. I was determined to prove that the mind could change the brain, which implies that the mind is separate from the brain but influencing the brain.

So I started off 30 years ago in practice and I decided to work with people with learning disabilities and with traumatic brain injury, specifically with the learning disabled communities, the older children. So, because we were also told back then that once you hit the age of 10, sort of 10 to 12, well then you’re too old to have much done for you. So you’d have to — you could get some remedial therapy and things like that but there wasn’t a huge amount that you could do for your brain.

So here I was coming out of university, keen to help people but being told that “Well, just teach your patients to compensate”. Well, I wasn’t going to do that, because I didn’t believe that that was the best thing to do for anyone.

I also know that thoughts are real things that occupy mental real estate. And that as we are thinking, we are choosing and we are building thoughts inside of our brain. I also believe that you’re as intelligent as you want to be, so the more you think deeply, the more intellectually  challenging — the challenges you put in front of yourself the more you’re going to grow your brain.

So my first few patients that I worked with in my practice group were patients with traumatic brain injury patients that had suffered from severe car accidents and had suffered severe traumatic brain injuries. I also worked with the older learning disabled population. I worked with people from heart attack victims, had strokes, various different things, where they presented with quite major damage inside their brain.

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And I decided to throw all traditional methods and started trying to understand the science of thought, and to work with things that actually were meaningful for them. One of the problems with doing the kind of therapy that I was trained to do, was something called carryover where you would teach a patient in a therapy room, give them therapy and then they would have to carry that over into their daily life and carryover wasn’t very good.

So I didn’t think that I would be very good therapist if I couldn’t teach them to change their brain and I couldn’t teach them to make a difference in their life. So I would ask them the question: What is the most important thing that you need to do? And obviously the students that were at school they wanted to work on schoolwork, people that had — former businessmen and women that were now sitting with brain damage, they wanted to get back to their former status. So that was my challenge.

Traumatic brain injury at that stage back in — and I talk about that stage, I’m talking 30 years ago, so back in the ‘80s where it was not accepted that your brain can change. Traumatic brain injury particularly was a disorder in search of data, which means that the scientists believed at that stage that the damage was so diffused that you couldn’t do anything for their brain.

So I started working with a — I had a patient that came to my practice. And this young woman was amazing. She had a terrible, terrible car accident. She was thrown from the car; she was basically in a coma for nearly two weeks. And in that day and age, when if someone was in a coma for longer than eight hours, their brain damage was considered irreversible. So the doctors told her parents that she’d be a vegetable.

Well, 14 months after her accident, the parents approached me. She wasn’t a vegetable, she’d come around; she had progressed. She was so determined she had used her mind, she had pushed through and she was functioning at around about a fourth-grade level. Now that may sound strange but she was 16 at the time of the accident. So she had lost 14 months, her peer group were going into 12th grade and she was now functioning at around a fourth-grade level.

So I was really nervous, that I have to be honest with you because I was just embarking on this field of research. I was learning — I was researching how the science of thought, how thoughts are formed, that thoughts are real that as you are thinking and choosing you’re actually building these — causing genetic expression in your brain and you’re growing these thoughts in your brain, and how can we do this effectively and what is the — can we control our thinking?

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So I told them, listen, you know, this is experimental but you can work with me. And 14 months post-accident is also not the greatest time to work with a patient, because they’ve kind of hit a plateau where they’re not really going to progress much more.

Long story short, eight months later this young girl not only did she catch up and close that gap but she went into 12th grade, she wrote 12th grade with her peer group, went on to finish school. She graduated, went on to get a degree, she changed dramatically.

And what did she do? The big thing about this young woman was she chose to direct her mind; she chose to use her intellect; she was determined, she thought she was thinking so hard about all the things that she was learning. She set with her schoolwork day in and day out for hours applying the techniques that I had been developing and learning.

What’s very interesting and you’ll see the first slide is of her IQ. Now with a traumatic brain injury, basically IQ generally goes down around 20 points, because the kind of damage with traumatic brain injury. Well, her IQ was 100 before the accident, it was 120 after the accident. So here with holes in her brain and brain damage she changed — she actually increased her intelligence.

Now I’m pretty convinced at this stage, because besides her I had been working with lots and lots of other patients seeing the same thing, when these students applied their mind their brain was changing, their academic results were changing. So I was working on the cognitive side, on the academic side, showing them how to process this information how to read, how to think, how to ask, answer and discuss their way through information, how to write that down and capture that information, how to make sure that they go back and compare what they had written down and look at the original work and do they understand and does this make sense, and then being able to reteach that and explain it. These students would spend hours working through these techniques and applying to their school work, and I saw change all over the place.

So then I thought, well this is great, this is wonderful, I’m seeing these incredible changes. And up here on this stage what you will see are two plants, and this green plant over here represents a healthy thought, and the little black tree over there represents an unhealthy thought, or a toxic thought from a negative emotion or a bad learning pattern. If you look — as you study the brain, you can actually see that as your thoughts are forming in the brain, they form on your neurons and they look like trees. So I really believed at that stage that as you were using your mind you could change your brain.