4.7-4.8

motivation

a need or desire that energizes and directs behavior.

instinct

a complex behavior that is rigidly patterned throughout a species and is unlearned.

physiological need

a basic bodily requirement.

drive-reduction theory

the idea that a physiological need creates an aroused state (a drive) that motivates an organism to satisfy the need.

homeostasis

a tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level.

incentive

a positive or negative environmental stimulus that motivates behavior.

Yerkes-Dodson law

the principle that performance increases with arousal only up to a point, beyond which performance decreases.

affiliation need

the need to build and maintain relationships and to feel part of a group.

self-determination theory

the theory that we feel motivated to satisfy our needs for competence, autonomy, and relatedness.

intrinsic motivation

the desire to perform a behavior effectively for its own sake.

extrinsic motivation

the desire to perform a behavior to receive promised rewards or avoid threatened punishment.

ostracism

deliberate social exclusion of individuals or groups.

achievement motivation

a desire for significant accomplishment, for mastery of skills or ideas, for control, and for attaining a high standard.

grit

in psychology, passion and perseverance in the pursuit of long-term goals.

glucose

the form of sugar that circulates in the blood and provides the major source of energy for body tissues. When its level is low, we feel hunger.

set point

the point at which the “weight thermostat” may be set. When the body falls below this weight, increased hunger and a lowered metabolic rate may combine to restore lost weight.

basal metabolic rate

the body’s resting rate of energy output.

obesity

defined as a body mass index (BMI) measurement of 30 or higher, which is calculated from our weight-to-height ratio. (Individuals who are overweight have a BMI of 25 or higher.)

emotion

a response of the whole organism, involving (1) physiological arousal,(2) expressive behaviors, and, most importantly, (3) conscious experience resulting from one’s interpretations.

polygraph

a machine used in attempts to detect lies; measures emotion-linked changes in perspiration, heart rate, and breathing.

facial feedback effect

the tendency of facial muscle states to trigger corresponding feelings such as fear, anger, or happiness.

behavior feedback effect

the tendency of behavior to influence our own and others’ thoughts, feelings, and actions.