Choosing sides: The left and right of the normal brain.

Publisher Website
Google Scholar
Abstract
The currently popular view of brain organization holds that the left cerbral hemisphere controls language processes, while the right hemisphere deals with various nonverbal activities, most particularly those involving visuospatial tasks. It is argued here that a substantial proportion of the population deviates from this modal model, and that the investigation of individual differences in brain organization is critical to our understanding of cerebral function. The present paper argues that it is possible to investigate such individual differences through careful studies of neurologically intact subjects. Deviations from the modal model are seen as being normal and genetically determined, rather than being pathological in origin. It is suggested that different functions, such as handedness, language, and visuospatial ability, are lateralized by relatively independent mechanisms, and therefore can be dissociated. Finally, some evidence for a positive relation between brain lateralization and cognitive ability is presented, and suggestions as to the possible mechanism are offered.