Development of Visual Stimulus-Seeking in Kittens *

Abstract

Three studies of the development of stimulus-seeking kittens are reported. In Experiment I kittens were housed, from before eye-opening, in total darkness or in a normal laboratory environment. They were given the opportunity, for one hour each day, to press a panel to illuminate a pattern in an otherwise dark experimental chamber. The normally-reared kittens scarcely availed themselves of this opportunity throughout the experiment. In contrast, the dark-reared kittens showed a sudden onset of visual stimulus-seeking around the end of the second month and thereafter pressed the panel for extended periods. This behaviour was maintained for as long as the cats were kept in the dark. In Experiment II, kittens were given varying periods of normal visual experience before being housed in the dark. The results showed that onset of stimulus-seeking was age-dependent and required only that the animals be housed in darkness at or after the end of the second month. Experiment III showed that stimulus-seeking did not extend to auditory stimuli and also that moving and stationary visual stimuli were equally effective in promoting the phenomenon. It is suggested that visual stimulus-seeking is one aspect of the maturation of a system underlying visual approach and exploratory behaviour. Evidence bearing on this point is discussed.