ABSTRACT
This chapter focuses on the brain, the magnum opus of millions of years of human evolution. The brain is examined by reinforcement sensitivity theory, a neurobiological theory of approach and avoidance offering a scientific theory of the hedonistic calculus. The theory posits three interacting brain systems guiding behavior: the behavioral approach system, the behavioral inhibition system, and the fight/flee/freeze system. Neuroscientists identify two forms of brain wiring: experience-expected and experience-dependent; the former reflecting our evolutionary history, and the latter reflecting each person’s unique developmental history. The environment is thus an important factor in brain wiring. Synaptogenesis is the creation of synaptic connections between neurons in experience-dependent fashion. Neurotransmitters of the serotonergic system and the testosterone/cortisol ratio are explored in terms of their effect on sexual and antisocial behaviors.
