PSYCH361 Chapter Notes - Chapter 4,5,6,7: Grey Matter, Neocortex, Brainstem
Brains appear to change in non-random ways as they increase in size. Ex) in higher organisms over evolutionary time, the neocortex has shown greater increases in size in comparison to the brain stem. As well, early primates have more neocortex in comparison to other early mammals & more brain areas devoted to visual processing. There is a particular gene called myh16 that influences the jaw muscles in humans and monkeys. Nonhuman primates have an intact version of the gene gives them strong jaws. Humans have a mutation in this gene gives smaller jaw muscles. The presence of smaller jaw muscles allowed for more of the area of the skull to be devoted to the brain. Human brain contains proteins that are more similar to those found in shellfish than to any other known food source suggests that shellfish was an important part of the human diet in an earlier period.