Forced-choice preferential looking acuity in very young kittens: a model for human development.

The development of visual acuity was studied longitudinally in young kittens, using a modification of the forced-choice preferential looking method (FPL). Acuity, defined as the spatial frequency which yields 70% correct responses by a naive observer, shows a 16-fold increase between 2 and 10 weeks of age. Acuity evaluated this way falls short of the acuity values obtained with the jumping stand or with electrophysiological methods. Acuity estimated with a criterion just above chance comes close to the resolution of the highest-resolving single cells in the striate cortex.