Chapter 1 - Elements of Brain Anatomy

Question 1

Why is the size of the human brain constrained?

Answer 1

It is constrained by the size of our head, which is limited by the size of the birth canal. Extension of the birth canal is limited by the upright posture and leg position of humans.

Question 2

What evolutionary strategies have humans developed to accommodate brain growth limits?

Answer 2

Neoteny - Longer period of (brain) development after birth
Folding the cortex - Extending the surface of the cortex without increasing the volume of the brain.
Synaptic pruning - Eliminating useless cells and connections.