Update: This post (and 2 others which I will post shortly) is older that this website. It was written and published back when I used a blog on Tumblr that you can locate here.
I’ve already learned some things from neuroscientist Richard Restak’s book Think Smart (another one of his on the human brain). Here’s a summary, with occasional quotations.
Different regions of the brain develop at different times. Until recently it was thought they developed simultaneously. Those involved with “primary functions such as movement, seeing, and hearing” (13) are the first to develop, “followed by language and thinking” (14). The brains of females reach maximum brain volume at a younger age than males.
Restak considered this book a prescription for keeping the brain healthy as we age. He starts off introducing the brain, and then covers what is best to feed the brain to optimize its functioning. He says that in the time in which he was sill deciding his career, neuroscience wasn’t a popular choice because of the general belief that not much could be done to treat/ cure people with brain diseases. He says that the appearance of brain imaging devices changed all that and that, at least in the time of his writing the book, neuroscience was one of the most popular careers chosen by people who had gone into science. (Sorry for the messy structure and order in my posts–I start off a little disorganized and then tend to organize myself.)
He explains the principle behind PET and fMRI. Both are brain imaging devices. Simply, he explains that the more-active regions of the brain are those that are consuming the most glucose and oxygen. Blood replenishes this glucose and oxygen, and so blood carries this important “food” to the brain regions that are the most active, and thus need it the most. The bloodiest brain regions are the most active. This also occurs with the body: the most active body areas receive the most blood. PET and fMRI record the blood flow to different brain regions, and therefore can see which brain regions are most active.
Something I’ve heard about a lot, and which Restak talked about, was brain plasticity. Basically (and I’m no expert, I’m just telling you what I understand) the brain has the capacity to rewire itself, and it does so all the time. It never loses this ability no matter how aged we are. Brain cells are called neurons, and connections between brain cells which allow them to communicate are called synapses. A single brain cell can have many synapses, many connections with other brain cells.
Getting a little off topic, but we lose some brain cells as we get older, after we’ve reached young adulthood. We also lose some synapses.
Anyway, the brain rewires itself according to its life experiences. Identical twins’ brains will grow more different as time passes. Brain structure and function varies per person because of plasticity, because what we do changes our brains. If we spend a lot of time doing a certain activity, we’ll get better at it. Related brain circuits will get stronger and more complex. At the same time, circuits that are not used will begin to fade, just like neurons that are not used die off. What is a circuit? Well as I understand it, a circuit is a chain of neurons that communicate to each other for a certain thought or action to take place.
Because of this reality, where what you do changes and specializes your brain, brain specialization occurs. If you are trained, you can look at the brain images of different people, as shown by PET scans or etc., and gain accurate information of what it is they do all the time.
Apparently London has some difficult-to-maneuver streets, because London cab drivers have been found to have a larger-than-normal hippocampus. No, that’s not the sea horse from Greek mythology.
Sorry, Percy Jackson fans.
In the brain (as opposed to the sea), the hippocampus is a structure “involved in spatial visualization and navigation” (7), which really does explain why London cab drivers’ hippocampi were enlarged.
Sorry, I’ll be serious now.
It might be hard to see the hippocampi in the image below, with there being many brain regions both color-coded and labeled, but they’re blue and in the center of the brain.
Hope you were able to manage that. Anyway, the message of that discovery is clear: brain plasticity is a reality.