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cerebral atrophy

degeneration and shrinkage of the brain, usually due to aging, disease, or injury. It is marked by enlargement of the surface clefts (sulci) and inner cavities (ventricles) of the brain. In normal aging there may be few or no cognitive effects, but cerebral atrophy may be secondary to more serious disorders, such as cerebrovascular disease, encephalitis, Alzheimer’s disease, or head injury. Also called brain atrophy.

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Psychology term of the day

May 10th 2024

guilty knowledge test

guilty knowledge test

a form of lie detection in which knowledge about the details of a crime is tested. A polygraph examiner presents examinees with multiple-choice questions concerning the crime, to which only the guilty party should know the correct answers; it is assumed that innocent examinees will see all options as equally plausible. The polygraph examiner measures the examinees’ physiological arousal as each option is presented and identifies which option produces the highest physiological response. Over a series of questions, if an individual consistently shows the greatest response to the correct option, the examiner may identify that person as untruthful in his or her denial of knowledge of the details of the crime. See also control question test; relevant–irrelevant test.