VARIATIONS IN LATERALIZED PROCESSING AMONG RIGHT-HANDERS - EFFECTS ON PATTERNS OF COGNITIVE PERFORMANCE

Two experiments investigated whether individual differences among right-handers in patterns of lateralized processing were related to level of performance on a variety of cognitive tasks presented under non-tachistoscopic conditions. Subjects were divided into two groups of individuals, those who characteristically have greater than average right-hemisphere involvement in functioning and those who characteristically have greater than average left-hemisphere involvement. In the first experiment we examined whether characteristic individual differences in hemispheric involvement could predict performance on a facial memory task. The group with relatively greater right-hemisphere involvement had better recognition memory than the group with relatively greater left-hemisphere involvement. In the second experiment, we examined whether individual differences in hemispheric involvement could predict performance on a larger set of cognitive tasks. The groups were administered two tasks selected to evaluate left-hemisphere function and two selected to evaluate right-hemisphere function. The results indicated that the groups differed in their profile of cognitive performance. Individuals with greater than average right-hemisphere involvement in processing tended to perform better on tasks indexing right-hemisphere function than on tasks indexing left-hemisphere function, whereas the opposite was true of individuals with greater than average left-hemisphere involvement. Collectively, the results of these two experiments indicate that individual differences in lateralized performance have important implications for individual differences in patterns of cognitive ability.