We saw how our brain got bigger in size over the last 3.5 million years, as we evolved from our earliest known human ancestor, the hominids. Is human brain evolving even today?
Absolutely. Why? Because,
Evolution never stops.
Our environment is always changing, and so our brain is also evolving, but so slowly (take home message #1) that we cannot see it unless several thousand generations have passed. And recent scientific evidence suggests this too. Our ancestors had to adapt to the altered conditions of ground-based threats, which triggered the brain size growth. How is the environment changing today?
After agriculture began about 12,000 years ago, and particularly the industrial revolution
of late 1800s and early 1900s, rapid advances in technology have considerably improved our life style, and made it fast-paced. Today a teenager’s brain processes more information in an hour than our forefathers did in their entire lifetime. Such increased demand on brain efficiency is likely to favor (Evolution point #2) a stronger brain in the foreseeable future.
Does “stronger” mean “bigger”? Posed another way,
Is our brain still getting bigger?
The best answer that I, or anybody else, can give you today is: Not necessarily. Even though we know how our environment has changed in the last few thousands of years, we still do not understand our brain well enough to know how exactly this change is driving its current evolutionary course.
We all agree, though, that modern human intelligence depends as much on the size of our brain as on its complex internal structure. And so, with each new generation getting smarter, it is possible that our brain is evolving internally, without getting bigger. Experts also seem to divide along these lines on their interpretation of the latest scientific evidence.
A quick peek at our brain:
If you cut open a human brain vertically in the middle, it looks like the picture here (click to enlarge). Our brain is packed with many internal organs, each connected to the others in intricate arrangements, and each performs a variety of complex tasks (much of which is still unknown).
For example, Prefrontal cortex (PFC) is the chief executive of our brain, because it is responsible for forethought, planning, impulse control, and decision making. Likewise, Limbic system (LS) is made up of a number of component organs that together govern our emotion, memory and behavior. Not surprisingly, proper functioning of PFC and LS is vital to develop a normal personality. (People with ADD often differ from others in this aspect, as I will talk about in detail elsewhere.)
If you like this post,
My life is a story of two contrasting worlds. To the others I am a scientist working in a top US university. But my private world is shaped by a lifelong struggle with ADD that I was born with, but did not know about until I was past 40. Here I present a unique perspective on adult ADD/ ADHD, drawing from the lessons of my own life and an extensive research on the subject.
(Sep 16, 2011 at 2:09 am)
This is very knowledge for the human brain.and about it self.