NEUROPSYCHOLOGICAL TEST-PERFORMANCE AND MEG-BASED BRAIN LATERALIZATION - SEX-DIFFERENCES

Magnetoencephalographic (MEG) auditory evoked fields (EF) were recorde d from left and right hemispheres of 9 normal males and 12 normal fema les. Source location of the 100 ms latency component (M100) was locali zed to superior temporal lobes bilaterally using an inverse solution a lgorithm. All subjects also were administered the Wechsler block desig n and visual reproduction subtests, and the California Verbal Learning Test (CVLT). M100 source locations demonstrated significant sex diffe rences in interhemispheric asymmetry. Males had source locations furth er anterior than females, with the differences most pronounced in the right hemisphere. Expected sex differences were found in neuropsycholo gical test performance, with males performing better on block design a d visual reproduction, and females performing better on the CVLT. Acro ss both sexes, block design scores correlated significantly with right hemisphere M100 location, with more anterior source locations associa ted with better performance. CVLT scores were negatively correlated wi th right hemisphere M100 source locations. These findings suggest MEG- based measures of interhemispheric asymmetry may be related to specifi c neuropsychological test performance measures.