Molecular psychology explores how actions relate to the physical structures of the brain. Basically, molecular psychology and molecular psychiatry reveal the ways that biology, genetics, and the physical structures of the brain influence our behavior. With roots in behavioral genetics, molecular psychology first began by studying geste in insects and beast subjects before moving on to humans. Behavioral genetics end to determine the inheritable causes of different ways of carrying. This field of study has revealed the ways that genetics affect psychological conditions and disorders.