Social Dominance and Cerebral Hemisphericity

Abstract

A neurosociological argument is presented which hypothesizes that persons in positions of social subdominance-black racial status, low and middle socioeconomic status (SES), and female sexual status will, in comparison to persons in positions of dominance-white, high SES, and male, be right-hemispheric, i.e., will perform best on a test lateralized to the right cerebral hemisphere and its appositional mode of thought as opposed to a test lateralized to the left hemisphere and its propositional mode of thought. Data from 1058 adults from two probability samples (excluding left-handers, housewives and unemployed persons) are analyzed. Appositional performance is measured by the Street Gestalt-Completion Test (A), propositional performance by the WAIS Similarities Subtest (P), and right-hemisphericity by (a-p)/(a + p). Multigroup discriminant function analysis and three-way analyses of variance produced the following results: (1) blacks are more right-hemispheric than are whites, with lower similarities performance and higher Street performance; (2) SES varies directly with Similarities performance, but not with Street performance; (3) there is a two way interaction between race and SES such that middle SES groups are most right-hemispheric for whites, and low SES groups, most right-hemispheric for blacks; (4) females are more right hemispheric than are males among blacks and lower SES whites, reflecting in part the superior performance of black females on the Street test.