Control of claw movements in cats.

In cats with the distal paw shaved and the claws painted with nail varnish, claw movements were recorded during the approach to a morsel of food with a conventional video camera; supplementary results were obtained with a high frequency video system. The claws can be protruded in two directions, either ventrally or more dorsalwards. Measurements of the outer contour of the paw suggest that these two modes are not due to differences in angular movements in the proximal interphalangeal joints; it is suggested that they depend on some (so far unknown) function in the distal interphalangeal joints. Differential movements of the claws of the different digits suggest some degree of individual control of the digits.