The role of local adaptation in flicker discrimination of brain-damaged (N = 16) and control (N = 16) Ss was investigated. Male adult patient's central binocular thresholds were measured before and after visual stimulation by a coarsely flickering light (10 cps) over 20 trials. In both groups there were significantly lower thresholds after stimulation and a progressive drop in both pre- and post-stimulation thresholds over trials. However, there were no significant group interactions. The methodological, empirical, and theoretical implications of these results are noted.
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