Ladd-Franklin theory

a formerly influential but now superseded theory of color vision. It is based on the notion that light of certain wavelengths causes substances to be released from a highly developed photosensitive molecule in the retina and that these substances stimulate the retina, causing the perception of red, green, or blue. [introduced in 1929 by Christine Ladd-Franklin]

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

January 3rd 2025

syphilis

n. a contagious disease caused by infection with the spirochete bacterium Treponema pallidum. Syphilis is usually a sexually transmitted disease, but it can be transmitted through a break or cut in the skin or mucous membrane; it can also be transmitted by an infected pregnant woman to an unborn child. Untreated, syphilis progressively destroys body tissues, particularly those of the heart and nervous system. See also cerebral syphilis; general paresis.