GABA -  The main inhibitory neurotransmitter in the brain.

Galvanic skin response -  An increase in the skin’s rate of electrical conductivity. It is also known as an electrodermal response.

Gambler’s fallacy -  The false belief that a chance event is more likely if it hasn’t happened recently.

Gate-control theory -  States that pain signals traveling from the body to the brain must go through a gate in the spinal cord.

Gender -  A learned distinction between masculinity and femininity.

Gender stereotypes -  Societal beliefs about the characteristics of males and females.

General adaptation syndrome -  The stress response of an organism, described by Hans Selye. The response has three stages: alarm, resistance, and exhaustion.

General intelligence factor (g) -  An ability that underlies all intelligent behavior, proposed by Charles Spearman.

Generalized anxiety disorder -  A disorder involving persistent and excessive anxiety or worry that lasts at least six months.

Generative -  The characteristic symbols of a language that can be combined to produce an infinite number of messages.

Genes -  Segments of DNA that function as hereditary units.

Germinal stage -  The two-week period after conception.

Gestalt psychology -  A German school of thought that studies how people organize visual information into patterns and forms.

Glial cells -  Cells that give structural support to neurons and nourish and insulate them.

Glucose -  A simple sugar that acts as an energy source for cells.

Glutamate -  The main excitatory neurotransmitter in the brain.

Grandiose delusion -  A belief centered around the idea that one is very important or famous.

Ground -  The background in which a figure stands when people organize visual information.

Group -  A social unit composed of two or more people who interact and depend on one another in some way.

Group cohesiveness -  The strength of the liking and commitment group members have toward one another and to the group.

Group polarization -  The tendency for a dominant point of view in a group to be strengthened to a more extreme position after a group discussion.

Groupthink -  The tendency of a close-knit group to emphasize consensus at the expense of critical thinking and rational decision making.