Find over 25,000 psychological definitions

dark adaptation

the ability of the eye to adjust to conditions of low illumination by means of an increased sensitivity to light. The bulk of the process takes 30 minutes and involves expansion of the pupils and retinal alterations, specifically the regeneration of rhodopsin and iodopsin. See also rod–cone break. Compare light adaptation.

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

May 25th 2024




1. the practice of taking committed action to achieve an end, particularly as it relates to a political or social goal. See also community action group; social action program.

2. in philosophy, the doctrine that any relationship between thought and reality is characterized by continuous activity on the part of the mind, rather than passive receptivity. —activist adj., n.