Effects of intelligence on the CVLT performance of neuropsychiatric patients.

摘要

This study examined the relationships between Wechsler Adult Intelligence Scale-Revised (WAIS-R; Wechsler, 1981) FSIQ and VIQ scores and performance on the California Verbal Learning Test (CVLT; Delis, Kramer, Kaplan, & Ober, 1987), a measure of verbal learning and memory capabilities, in a neuropsychiatric sample. The study included 504 male veteran participants, ages 22--87, with 3--24 years of education, and WAIS-R FSIQ scores ranging from 58--138. Pearson product moment correlations revealed that WAIS-R FSIQs had significantly higher correlations than WAIS-R VIQs with most of the selected CVLT variables (Total Words Trials 1--5, Long Delay Free Recall, Semantic Clustering, and Total Intrusions), whereas VIQ correlated more highly with Serial Clustering.; Hierarchical multiple regression analyses revealed that WAIS-R FSIQ accounted for up to 16.3% of the variance in CVLT Total Words Trials 1--5 performance, and up to 12.3% of the variance in CVLT Long Delay Free Recall performance. Three additional hierarchical multiple regression analyses found that WAIS-R FSIQ accounted for up to 4.4% of the variance in CVLT Semantic Clustering, and up to 5.1% of the variance in CVLT Total Intrusions. Conversely, WAIS-R VIQ did not contribute significantly to performance on CVLT Serial Clustering.; After the sample was divided into three level of intelligence groups (i.e. low, middle, high), a one-way analysis of variance (ANOVA) indicated that neuropsychiatric patients with higher IQ scores performed significantly better than those with lower IQ scores on CVLT Total Words Trials 1--5 and Long Delay Free Recall indices. Three additional ANOVAs revealed that neuropsychiatric patients with higher IQ scores also performed significantly better than those with lower IQ scores on CVLT Semantic Clustering and Total Intrusions, but not on Serial Clustering. The same results were found after matching participants on age and education across IQ groups.; Overall, these results indicated that intelligence does correlate with performance on selected CVLT memory indices, and should be considered when interpreting test performance in a neuropsychiatric population. In addition, these findings were congruent with previous studies reporting that scores on intelligence tests correlate with scores on memory tests, indicating a relationship between intelligence and memory.