Facial-feedback hypothesis -  The idea that the brain uses feedback from facial muscles to recognize emotions that are being experienced.

Factor analysis -  A statistical procedure that clusters variables into dimensions depending on similarities among the variables.

Falsifiability -  The ability of a theory or hypothesis to be rejected.

Family studies -  Studies in which researchers examine trait similarities among members of a family to figure out whether that trait might be inherited.

Family therapy -  A type of therapy in which a therapist sees two or more members of a family at the same time.

Feature detectors -  Specialized neurons that are activated by specific features of the environment.

Fee for service -  An arrangement for health care in which people pay providers for health care services.

Feigned scarcity -  Implying that a product is in scarce supply, even when it is not, in order to increase demand for it.

Fetal alcohol syndrome -  A collection of symptoms that may be present in babies of alcoholic mothers who drank heavily in pregnancy.

Fetal stage -  The last stage of prenatal development, lasting from two months after conception until birth.

Figure -  What stands out when people organize visual information.

Fixation -  An inability to progress normally from one psychosexual stage of development into another.

Fixed-interval schedule -  A reinforcement schedule in which reinforcement happens after a set amount of time.

Fixed-ratio schedule -  A reinforcement schedule in which reinforcement happens after a set number of responses.

Flashbulb memories -  Vivid, detailed memories of important events.

Flooding -  A type of exposure therapy in which the client is exposed to a feared stimulus suddenly rather than gradually.

Flynn effect -  Phenomenon showing that people’s performance on IQ tests has improved over time in industrialized countries.

Foot-in-the-door phenomenon -  The tendency to agree to a difficult request if one has first agreed to an easy request.

Forebrain -  The biggest and most complex part of the brain, which includes structures such as the thalamus, the hypothalamus, the limbic system, and the cerebrum.

Forgetting curve -  A graph that shows how quickly learned information is forgotten over time.

Fovea -  The center of the retina, where vision is sharpest.

Free association -  A psychoanalytic technique that involves having the client verbalize all thoughts that come to mind.

Frequency -  The number of times per second a sound wave cycles from the highest to the lowest point.

Frequency theory -  A theory explaining how people discriminate low-pitched sounds that have a frequency below 1000 Hz.

Frustration -  The experience of being thwarted in the process of achieving a goal.

Frustration-aggression hypothesis -  A hypothesis stating that aggression is always caused by frustration.

Functional fixedness -  The tendency to think only of an object’s most common use in solving a problem.

Fundamental attribution error -  The tendency to attribute other people’s behavior to internal factors such as personality traits, abilities, and feelings. It is also called correspondence bias.