Individual Differences in Hemispheric Specialization

It has long been recognized that the left cerebral hemisphere is specialized for language and possibly other symbolic process, and that the right hemisphere has a visuospatial specialization. Aphasia affecting the cerebral hemisphere on the same side as the preferred hand has also long been understood. Individual variation in degree and direction of specialization due to gender and handedness has, until recently, been regarded as a barrier to the investigation of lateralization, and at the same time individual differences have been used to explain differences in lateralization measurements on a post-hoc basis. This volume provides cross comparisons of several methods for assessing hemispheric specialization, methods such as perceptualbehavioral, clinicalneurological, electrophysiological, and real-time techniques for assessment of cerebral orientation. Errors of assessment should thereby be differentiable from individual variations in hemispheric specialization. It is the consensus of the authors of theses research notes that hemispheric specialization may reemerge, not as a monolithic, absolute structural concept, but as a dynamic process, modulating the utilization by differential strategy, activation, and arousal, of a relative structural specialization of the hemisphere in individual subjects. The importance of these concepts for psychopathology is also considered.