A factor analytical investigation of the Multilingual Aphasia Examination

Language and cognition are thought to be closely related. The Multilingual Aphasia Examination (MAE) is a widely used test battery to assess language functions. The relationship of the MAE variables to cognition has not been well characterized. In this study, we examined how specific language dimensions relate to markers of general intelligence in a mixed neuropsychiatric population.;To this end, we identified specific language dimensions that are measured by the subtests of the MAE. We performed principal component analysis to understand how these language dimensions relate to markers of general intelligence. We used factor scores generated from the Wechsler Adult Intelligence Scales- Revised (WAIS-R) as measures of general intelligence. We also examined the relationship of age and level of education to the language dimensions measured by the MAE.;Three factors, representing aspects of general intelligence, Verbal Comprehension (VC), Perceptual Organization (PO) and Freedom From Distractibility (FFD) were generated from scores on the WAIS-R. Four language factors, namely repetition, naming, verbal fluency and comprehension, were identified by principal component analysis of scores on MAE subtests. Our results support the long-held idea that naming, repetition, verbal fluency and comprehension are distinct linguistic constructs.;In addition, naming was found to be robustly associated with crystallized verbal knowledge, as measured by the WAIS-R VC. Verbal fluency and repetition were correlated with the WAIS-R FFD. The comprehension factor was not strongly related to any of the WAIS-R factors. We also found an age-related decline in verbal fluency and auditory comprehension. In contrast, increasing levels of education were found to be associated with an increase in repetition and naming performance levels.;We also examined the relationships of the ACWP, RCWP, Written Spelling and Oral Spelling with the other MAE and WAIS-R factors. We found that while the ACWP and RCWP were strongly correlated with the WAIS-R VC construct, the spelling tests were mostly associated with the WAIS-R FFD construct.