Excessive postrotary nystagmus duration in learning-disabled children.

The Southern California Sensory Integration Test results of 109 learning-disabled children were reviewed and analyzed to investigate the hypothesis that learning-disabled children with excessive postrotary nystagmus durations display greater neuropsychological impairment than learning-disabled children with normal or depressed postrotary nystagmus. The findings supported the hypothesis that learning-disabled children judged to have relatively greater neuropsychological involvement exhibited significantly longer postrotary nystagmus durations. Data analysis revealed that six Southern California Sensory Integration Tests assumed to measure cortical level functions shared significant variance with excessive Southern California Postrotary Nystagmus Test (SCPNT) scores. A similar relationship was not found for normal or depressed SCPNT scores. A connection between cortical level versus brain-stem level central nervous system dysfunction, nystagmus, and learning disorder is discussed.