Movement discrimination capacities in the cat.

Abstract

Cats were trained to discriminate moving from nonmoving targets or one direction of movement from another. Various stimulus changes, e.g., size, direction and rate, were then introduced as a test for generalization of the dimension of movement. Thresholds for detection for minimal movement were also determined. For cats, discrimination of movement was more difficult than discriminations based on brightness; the dimension of movement was completely generalized across stimulus configuration but incompletely generalized for direction of movement; the mean movement detection threshold was 3.3.degree./s; the thresholds for minimal movement and direction of movement were essentially identical; and stimulus-viewing strategies played an important role in the threshold determinations. The results of the generalization tests were consistent with the physiological properties of neurons sensitive to movement in the cat visual system. The movement threshold values suggested that resolution and slow movement thresholds are correlated.