Dr. Lara Boyd, physical therapist and neuroscientist, says After Watching This, Your Brain Will Not Be The Same at TEDxVancouver. Below is the full transcript. This event took place TEDxVancouver at Rogers Arena on November 14, 2015.
Listen to the MP3 Audio here: After watching this, your brain will not be the same by Lara Boyd at TEDxVancouver
So how do we learn? And why does some of us learn things more easily than others? So, as I just mentioned, I’m Dr. Lara Boyd. I am a brain researcher here at the University of British Columbia. These are the questions that fascinate me.
So brain research is one of the great frontiers in the understanding of human physiology, and also in the consideration of what makes us who we are. It’s an amazing time to be a brain researcher and, I would argue to you that I have the most interesting job in the world.
What we know about the brain is changing at a breathtaking pace, and much of what we thought we knew and understood about the brain turns out to be not true, or incomplete. Now some of these misconceptions are more obvious than others. For example, we used to think that after childhood the brain did not, really could not change. And it turns out that nothing can be farther than the truth.
Another misconception about the brain is that you only use parts of it at any given time and silent when you do nothing. Well, this is also untrue. It turns out that even when you are at a rest, and thinking of nothing, your brain is highly active. So it’s been advances in technology, such as MRI, that’s allowed us to make these and many other important discoveries. And perhaps the most exciting, the most interesting and transformative of these discoveries is that, every time you learn a new fact or skill, you change your brain. It’s something we call neuroplasticity.
So as little as least 25 years ago we thought that after about puberty, the only changes that took place in the brain were negative. The loss of brain cells with aging, resulted damage, like a stroke. And then studies began to show remarkable amounts of reorganization in the adult brain. And the ensuing research has shown us that all of our behaviors change our brain. That these changes are not limited by age, it’s good news right? And in fact they are taking place all the time. And very importantly, brain reorganization helps to support recovery after you damage your brain.
The key to each of these changes is neuroplasticity. So what does it look like? So your brain can change in three very basic ways to support learning. And the first is chemical. So brain actually functions by transferring chemicals signals between brain cells, what we call neurons, and this triggers series of actions and reactions. So to support learning your brain can increase the amount of the concentrations of these chemical signaling that’s taking place between neurons. Now because this kind of change can happen rapidly, this supports short term memory or the short term improvement in the performance of a motor skill.
The second way that the brain can change to support learning is by altering its structure. So during learning the brain can change the connections between neurons. Now here the physical structure of the brain is actually changing so this takes a bit more time. These types of changes are related to the long term memory, the long term improvement in a motor skill.
Now these processes they interact, and let me give you an example of how. So we’ve all tried to learn a new motor skill. Maybe playing a piano, maybe learning to juggle. You have had the experience of getting better and better within a single session of practice, and thinking “I have got it”.
And then maybe you return the next day and all those improvements from the day before they are lost. What happened? Well in the short term, your brain was able to increase the chemical signaling between your neurons. But for some reason those changes did not induce the structural change that are necessary to support long term memory. Remember that long term memories take time. And what you see in the short term does not reflect learning. It’s these physical changes that are now going to support long term memories, and chemical changes that support short term memories.
Structural changes also can lead to integrated networks of brain regions that function together to support learning. And it can also lead to certain brain regions that are important for very specific behaviors to change your structure or to enlarge. So here are some examples of that. So people who read braille they have larger hand sensory areas in their brain than those of us who don’t. Your dominant hand motor region, which is on the left side of your brain, if you are right handed, is larger than the other side. And research shows that London taxi cab drivers who actually have to memorize a map of London to get their taxi cab license, they have larger brain regions devoted to spacial, or mapping memories.
Now the last way that your brain can change to support learning is by altering its function. As you use a brain region it becomes more and more excitable and easy to use again. And as your brain has these areas that increase their excitability the brain shifts how and when they are activated. With learning we see that whole networks of brain activity are shifting and changing.
So neuroplasticity is supported by chemical, by structural and by functional changes. And these are happening across the whole brain. They can occur in isolation from one another, but most often they take place in concert. Together they support learning. And they’re taking place all the time.
So I just told you really how awesomely neuroplastic your brain is. So why can’t you learn anything you choose to with ease? Why do our kids sometimes fail in school? Why as we age do we tend to forget things? And why don’t people fully recover from brain damage? That is, what is it that limits and facilitates neuroplasticity?
And so this is what I study. I study specifically how it relates to recovery from stroke. So recently stroke dropped from being the third leading cause of the death in the United States to be the fourth leading cause of the death. Great news, right? But actually it turns out that the numbers of people having a stroke has not declined. We are just better at keeping people alive after a severe stroke. It turns out to be very difficult to help the brain recover from stroke. And frankly we have failed to develop effective rehabilitation interventions.
The net result of this is that stroke is the leading cause of long term disability in adults in the world. Individuals with stroke are younger and tending to live longer with that disability. And research from my group actually shows that the health related quality of life of Canadians with stroke has declined.
So clearly we need to be better at helping people recover from stroke. And this is an enormous societal problem, and it’s one that we are not solving. So what can be done? One thing is absolutely clear: the best driver of neuroplastic change in your brain is your behavior. The problem is that the dose of behavior, the dose of practice that’s required to learn new and relearn old motor skills, it’s very large. And how to effectively deliver these large doses of practice is a very difficult problem. It’s also a very expensive problem.