Neuropsychological changes in olivopontocerebellar atrophy

We used standardized neuropsychological measures of intellectual, cognitive, psychomotor, and emotional functioning to compare 39 patients with olivopontocerebellar atrophy and 25 normal controls of similar age. The patients reflected greater depression, anxiety, and subjective emotional discomfort than did the control subjects. While 4 of the patients had below-normal IQ scores (Wechsler Adult Intelligence Scale [WAIS-R] Full-Scale IQ [FSIQ] less than 80), their clinical histories suggested lifelong functioning at such levels. As a group, the patients were not abnormal in general intellectual functioning and related cognitive abilities (WAIS-R FSIQ, mean [+/- SD], 93.46 +/- 13.19; Wechsler Memory Scale mental quotient, 108.95 +/- 17.43). These scores were lower than those of the normal controls (WAIS-R FSIQ, 113.72 +/- 12.68; mental quotient, 127.80 +/- 12.40); however, the controls were a highly educated group with intelligence levels that were higher than those of the average population. Moreover, when education and motor dysfunction were statistically covaried, no significant differences between the patients and the normal controls were apparent on the cognitive and intellectual tasks. Further analysis of specific memory performance in a subgroup of patients and controls matched for age, sex, and education yielded findings that were comparable with the overall group analysis. We conclude that motor dysfunction and depressed mood could leave patients with olivopontocerebellar atrophy appearing to be impaired in memory, even demented, when they are not.