A Teensy Brain July 20, 2007Posted by Mrs Weird Scientist in Easy As Pie, Human Body, Psychology and Behavior.
To this day, there’s still the idea that a big brain means someone is smarter and a smaller brain means someone lacks intelligence. Silly playground insults like ‘pea brain’ were rampant when I was a kid. At the same time, there is some relevance between brain size and normal brain functioning. A certain amount of brain matter is necessary to allow us to function in a healthy capacity. That’s why it was surprising for doctors to find that a 44 year-old man with an abnormally tiny brain actually lives a very normal life, despite his brain size.
Credit: Pictures are from The Lancet (Feuillet et al.) See that large black space on the left two pictures there? That’s all the fluid that essentially took over the man’s brain. The pictures on the right are for comparison- just to show a normal, healthy brain.
What Happened To The Man?
The story begins when the man was an infant. He had a shunt placed in his head to drain out fluid. Then, when he was 14 years-old, this shunt was removed. Fast forward to his adult years now-the man is 44 years-old and goes into the hospital after feeling some weakness in his left leg. The doctors there take a medical history, which is standard procedure to help diagnose a patient. Of course, they find out about the shunt that he originally had inserted into his head and then later removed. It was decided to take a special scan called a computed tomography (CT) scan. The shocking result? The man showed enormous enlargement of his lateral ventricles. The lateral ventricles are important because, although small, they hold a substance called cerebrospinal fluid, which is vital to protect and cushion the brain.
What Intelligence Tests Say
You’re maybe thinking that his intelligence was way down. I mean, with so much of his brain volume affected by fluid, how could such a small amount of brain matter not leave him with major intelligence problems. Nope. Intelligence testing showed that the man has an IQ of 75-it’s lower than the usual 100 but by no means considered mentally disabled. The neurologist who looked at the scan was Lionel Furrieut at the Mediterranean University in Marseille, France. Although he didn’t use any software to actually measure the amount of brain volume, he visually estimated the reduction of the man’s brain to be between 50 and 75 percent. It’s simply phenomenal to imagine that sort of a reduction yet the man still functions very well.
Brain what? Plasticity! It’s the brain’s ability to absorb a certain amount of trauma and adapt by taking up functions in parts of the brain that usually wouldn’t perform that function. The man’s brain plasticity developed over the three decades of fluid build-up in the brain, so parts of his brain were able to take on roles that other damaged parts were no longer able to do.
So, despite this man’s very tiny brain, he is an incredible example of how smart the human brain really is because to a certain extent, it can make up for lost parts. I think those kids who shout ‘pea brain’ should all read this story!