Hemisphericity: A critical review

Hemisphericity refers to the idea that people may rely on a preferred mode of cognitive processing, which is linked to activity on the part of the left or right cerebral hemispheres. Four methods have been used in hemisphericity research: lateral eye-movements, electrophysiological measures, questionnaires and cognitive tests. It is demonstrated that none has been properly validated with respect to the purposes for which they are employed in studies of hemisphericity. It is argued that the idea of hemisphericity lacks adequate foundation and that, because of the assumptions implicit in the idea of hemisphericity, it will never be possible to provide such a foundation. The idea is a misleading one which should be abandoned.