Chapter 3 is all about the Biological aspects of Psychology. It starts talking about the neurons, which are the nerve cells the brain depend on to be able to function. Then the action potentials that make neurons so affective and neurotransmitters that either excite or inhibit the nervous system. The chapter then continues to talk about how our brains change from infancy to adulthood, and also after major injuries. Then the brain, specifically its central and peripheral nervous systems. Lastly, it talks about the endocrine system and the brain in action.
The most interesting section to me, was not the fact that our brain changes, but HOW it changes. Our brains are most easily susceptible to change before our nervous system sets in. During one of the four main ways neurons in the brain changes, pruning, about 70% of our neurons die off. I wouldn't think this is such a good thing, to lose so many of our neurons over a short time period. You would assume that more neurons would mean that our brains can process a lot more information. But actually, less neurons equals a more efficient way of processing information.
A theory of infant autism is that due to the lack of pruning, autistic children have unusually large brains.
Ofcourse, we all know or assume that our brains change the more we learn. When we learn more about certain topics, axons pertaining to that subject expand. Also when we submerge ourselves in certain environments, our dendrites expand, creating more branches.
Location of axons and dendrites on a neuron.