Motivation is an internal process that makes a person move toward a goal.
Motivation may be extrinsic, intrinsic, or both.
Drive reduction theories of motivation suggest that people act in order
to reduce needs and maintain a constant physiological state.
Abraham Maslow proposed that there is a hierarchy of needs
and that people pay attention to higher needs only when lower ones are satisfied.
Needs may be innate or learned. Learned needs are determined
by values. Both innate and learned needs are influenced by society and
A genetically influenced set point may allow people to keep their weight
The lateral hypothalamus and the ventromedial
andparaventricular nuclei of the hypothalamus play key roles in regulating
The digestive system and hormones such as insulin and leptin
also regulate hunger.
Environmental influences on hunger include availability of
foods,preferences, habits, memory,
stress, andcultural attitudes.
Alfred Kinsey was one of the first people to give a modern account of
William Masters and Virginia Johnson described the human
The sexual response cycle has four phases:
excitement,plateau, orgasm, and resolution.
Testosterone increases sex drive, and sexual activity increases testosterone.
Psychological influences on sex drive include internal and external erotic
stimuli, desires, and cultural context.
Researchers have found that there are some gender differences in sexual behavior and
partner choice. Both evolutionary and sociocultural explanations can account for these
Estimates of the prevalence of homosexuality vary, and the causes of homosexuality
Researchers have suggested that biological factors including hormone
levels, genes, prenatal environment, and brain
anatomy could influence sexual orientation.
Psychologists have proposed several theories about how environment might influence
homosexuality, but research has failed to support these theories.
Researchers often use the thematic apperception test (TAT) to measure the
need for achievement.
People who have a high achievement motivation tend to be persistent and
hardworking. They are able to delay gratification to meet long-term goals, and they tend to
choose careers that allow them to compete with others.
People achieve the most when they have high expectations of
success,incentives that reward competence, control over
tasks,opportunities to achieve, and effective goals.
Goals are most effective when they are specific, moderately
difficult, and framed in terms of what must be done rather than what must