Simultaneous colour discrimination in chicks is improved by brief exposure to light.

Dark-reared chicks were exposed to white light for 1 h at age 24 h. At 48 h these chicks, and others kept in the dark throughout, were given the opportunity to obtain a heat reward by choosing the correct arm in a Y maze. The discriminanda were red and blue illuminated circles, each being the positive stimulus for half the chicks. Light-exposure resulted in faster learning, especially when the positive stimulus was blue. This is taken as further support for the view that brief exposure to light activates the visual system non-specifically, affecting many kinds of visually guided behavior.