Glossary D

Decay refers to a hypothesized process of forgetting in which material is thought to erode, break apart, or otherwise disintegrate or fade. Decay occurs when simply the passage of time causes an individual to forget. In the study of sensation and perception, Decay is defined as the decrease in the sound signal that occurs at the end of a tone.

Decay theory refers to a theory that asserts that information is forgotten because of the gradual disappearance, rather than displacement, of the memory trace. Decay theory is an explanation for loss of information in short-term memory based on the notion that the physiological effects of stimulation fade. Decay theory is similar to Fading in connection with forgetting in long-term memory. (see Fading.)

Deceleration describes an event in which the brain is in motion traveling at a certain speed and then stops abruptly.
Decency refers to conformity to recognized standards of propriety, good taste, and modesty as defined by a particular group. Standards of decency differ among groups or cultures. What might be decent to one group or culture might not be decent to other groups or cultures. Example: in some countries in Africa it is decent to be bare breasted even in oublic, but in other countries it is indecent to be bare breasted when in public.

Decentering is when a person learns to recognize that he or she is not the center of the universe, and that there is not as much emphasis on humans as we think there is.

Decentralization is a term used in industrial and organizational psychology that refers to a process which occurs when lower-level employees have the right to make important decisions instead of management making all the decisions.
Deception refers to concealment of the purpose and procedures of a study from the participants.

Decibel is defined as a unit that indicates the presence of a tone relative to a reference pressure: dB 20 log (p/po) where p is the pressure of the tone and po is the reference pressure.