During the first lecture of introductory psychology, I usually give my students a true/false quiz containing myths about the brain (and other areas of psychology). Invariably students mark down some of these statements as true, and we spend much of the class dispelling these myths.
We use 10% of our brain
We see this myth perpetuated in the movie Lucy where the main character is able to reach her “full” potential by taking a drug that allows her to tap into the remaining 90 percent of her brain. She’s instantly smarter and even gains superpowers like telepathy. We know however, from ample research and basic knowledge about how the brain works, that this is not true.
The human brain only weighs on average 3 pounds (compare that to a sperm whale’s 17 pound brain!), but it takes up 20 percent of our body’s resources (e.g., oxygen, glucose). For such a small organ it’s pretty resource intensive, and for good reason. The brain is made up of tons of networks of neurons (the basic unit of our nervous system) constantly talking to each other, and brain imaging techniques such as fMRI scans have shown that our brains are constantly active over a 24-hour period. Your brain is working even when you’re unconscious—research shows that your memories are consolidated and transferred to long-term memory stores during sleep. Lastly, in studies of trauma to the brain, significant dysfunction can occur even when small areas of the brain are damaged, and that’s because we have evolved specific functions for particular areas of the brain and need all of them working together.
We’re left-brained or right-brained
Pop psychology would have us believe that we’re especially analytical and logical if we’re left-brained, and creative and intuitive if we’re right-brained. Research has shown some differences between the two hemispheres of the brain. For example, for many people, language processing is primarily located in the left hemisphere, and the right hemisphere excels with things such as emotion expression and spatial ability. However, these differences are not absolute; there is only a very slight bias for one hemisphere.
Your brain needs both hemispheres of the brain for you to function on a daily basis. For example, the brain areas responsible for information processing (four different lobes of the cerebral cortex) reside in both hemispheres of the brain. The two hemispheres of the brain also need to talk to each other, and we are impacted when that connection is lost (see case-studies of “split-brain” patients). Your daily functioning requires a coordinated effort and communication between all brain areas to give you a clear sense of the world around you.
Consider how these myths can affect your teaching and your students’ learning. As an instructor I try to convey to my students the enormous potential their brains have in working and processing information, and most importantly, how the brain is constantly changing (my favourite concept to teach is neuroplasticity). Research shows how much our brains can grow and change if we work on it like a muscle, and we’re definitely not constrained by lack of brain activity or the “types” of brains we have.