Asymmetric processing in perception of apparent movement

Asymmetric processing of movement-simulated spatial arrays was studied by the method of successive random presentation to the left or right visual half-field. On each trial two arrays consisting of between 2 and 5 dots were tachistoscopically presented in rapid succession to one visual half-field, in such a way as to simulate movement of the dots. Subjects' response choice represented a presumed continuation of the apparent movement. This was assumed to involve a process of prediction in that subjects inferred the trajectory of the stimulus dots in order to choose a response array. Response accuracy, which was measured by the number of correct response arrays chosen from a three-array series on each trial, was greater when dot arrays were presented to the left visual half-field than when they were presented to the right half-field. It was concluded that the right hemisphere of the brain plays an important role in processing for this task, and task features that may be attributed to right hemisphere processing were discussed.