I went to school through the 80s and 90s. Then I started teaching at the turn of the century (1998) and continued until 2024. I tell you this so that you will understand how many fads I have seen in education. As sure as the return of bell-bottom jeans as "flared-leg," some of those educations fades have faded and then returned under new names. Fashion has to have fads, or the fashion industry would die as we all just held onto our clothes until they wore out. Education doesn't have to be that way. The education curriculum and product industry needs it to be that way, but actual teaching doesn't. We can find out what works - there's tons of research available - and do those things.
Some of the things that prevent us from doing that are out of our control. We can't prevent administrative initiatives. But there is one that is in our control - our own wrong beliefs. Teachers often hold myths about the brain that prevent them from doing what works. I'm not judging them. Many of these myths were taught to us by trusted sources - some even in our teacher preparation classes or professional development sessions. Additionally, when you start looking into the history of these myths, you find that there was a certain logic at the time they were proposed. As G.K. Chesterton wrote, "All heresy is a truth taught out of proportion," most brain myths begin with a kernel of truth.
I'm developing a presentation for conferences on myths that are popularly held about the brain, looking into how their kernels of truth ballooned into myths and what that means for our classrooms. I have to fit 3-4 myths into a 40 minute presentation (Let's be real; I'll never get to the 4th), so I thought I would do a deeper dive into each of them on the blog. This one remains prevalent in popular culture.
We have all heard someone reference this myth. "Just imagine what we could do," they say, "if we could access the unused parts of our brain." Meanwhile, every part of our brain is busy processing sensory input, interpreting the meaning of smells and sounds, and aiding us in making decisions, all while sending signals to our heart to beat, our diaphragm to contract and relax, and our motor neurons to pick up objects and write things. Our brains work hard, and we talk about them like they are lazy, only doing 10% of their job.
So, how did we come to believe this? It's history is a bit convoluted.
This is William James. He was a Harvard psychology professor at the turn of the 20th century, specializing in prodigies - you know, those people who could perform a symphony at the age of three or could carry out complex math procedures long before most children. In a lecture, he said a fairly obvious fact - "Most people only live up to a fraction of their mental potential." Notice that he did not connect it to neurology and he did not use a number. He was generalizing about the motivation of the general population as compared to the passionate practice of prodigies. But, it planted a seed.
We associate a lot of thing with the roaring twenties - flappers, jazz, parties, and women's suffrage. We likely don't think of self help, but they certainly did. Self help was huge, especially in publishing. Many people read books about how to improve themselves, and some of them latched onto the idea that we had unlimited brain capacity that we weren't tapping into.
But the book that turned a kernel of truth (we don't live up to our potential) into an epic myth (we are neurologically limited to 10%) was Dale Carnegie's How to Win Friends and Influence People. Nearly everyone in America read this book, and it remains one of the best sellers of all time. It's preface was the first to state the myth in explicit terms, that we only use 10% of our brains. The massive popularity of this book embedded the idea into the population.
And it seems to be a particularly sticky idea, with movies using this concept as a plot device as recently as 2013 (Lucy - not a recommendation, not even Scarlett Johansson could make it good). This is in spite of concrete evidence from MRIs and PET scans showing that we use our entire brains. There is, in fact, competition for real estate in the brain. If you lost your sight and were taught to read Braille, that data from your fingers would be processed by the area previously used to interpret data from the eyes. There are no abandoned amusement parks in your brain.
So what's the truth? Is your brain limited? Or is there no limit to your brain's potential.
Yes.
Seriously, knowing the ways in which your brain is limited and the ways in which it is not can be super helpful in your classroom.
- Working Memory - The simplest definition of working memory is information and process that are held in active consciousness at any given moment. This is limited. How much varies by individual, but the generally agreed upon average is four. This limitation makes multi-tasking impossible, and it means the presentation of class content must be done carefully and in manageable doses. Knowing that means we can plan for it. Knowing this also means we can reduce cognitive load that is not related to what we are teaching. Classrooms are often a continuous stream of sensory input. While we can't do much about some of that input (the humming of the student next to you or the aroma that is carried by those who just left PE), there are some that we can. We can reduce the number of items on our classroom walls. We can stop playing music in the background of lessons. We can refrain from using scent diffusers. Those are just inputs we don't need to have competing with our content in a student's working memory.
- Long Term Memory - As far as we can tell, there is no limit to how much can be stored in our long term memory. Furthermore, information that is stored in long term memory is not a strain on working memory. What does this mean for your classroom? It means asking students to memorize things will INCREASE their ability to perform higher level task with it. Do they have to memorize everything? No. But they should memorize things you will want them to use or think carefully about. Don't be afraid or ashamed of asking kids to commit things to their long term memory (Yes, even in the age of Google and AI. A fact in the student's mind is more useful than a fact held external to it.)
Achieving our potential is a life goal for all of us, but it doesn't equate to using our whole brain. If it did, we would have been successful from the moment we were born. It equates to showing up every day, using our limited working memory
