Find over 25,000 psychological definitions


vomeronasal system

a set of specialized receptor cells that in nonhuman mammals is sensitive to pheromones and thus plays an important role in the sexual behavior and reproductive physiology of these animals. In humans, this system responds physiologically to chemical stimulation and, in turn, excites brain centers, but its role in human olfaction is not known. Also called Jacobson’s organ; vomeronasal organ (VNO).

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

February 23rd 2025

vacuum activity

vacuum activity

in classical ethology, the occurrence of a fixed action pattern in the absence of the usual external stimulus (the releaser, or sign stimulus) that triggers the pattern. This is believed to be caused by a build-up of action-specific or motivational energy that overrides the innate releasing mechanism. Also called vacuum response. [proposed by Konrad Lorenz]