Hemispheric asymmetries of affective processing as determined by the Minnesota Multiphasic Personality Inventory

Patients with left hemisphere disease have been noted to be depressed while those with right hemisphere disease appear indifferent. While patients with left hemisphere disease frequently have a greater cognitive deficit, patients with right hemisphere disease have difficulty in expressing affectively intoned speech. The Minnesota Multiphasic Personality Inventory (MMPI) can demonstrate underlying affective experience and is not dependent on affectively intoned speech. The purpose of this study was to determine whether a difference in affective moods, as assessed by the MMPI, was related to laterality of lesion in patients matched for severity of cognitive and motor dysfunction. Seven of the 16 subjects with left hemisphere dysfunction and none of the eight subjects with right hemisphere dysfunction showed an elevation on the depression scale. This observation not only confirms previous clinical observations but also demonstrates that these asymmetries cannot be ascribed completely to hemisphere-related differences in cognitive deficits or expressive abilities.