The relationship between cerebral lateralization and cognitive ability: suggested criteria for empirical tests.

Many recent investigations in cognitive neuropsychology have been devoted to a fundamental question: are individual differences in cerebral lateralization reliably associated with differences in cognitive ability? The results have been highly inconsistent and inconclusive, with some studies showing a relationship, others not. We propose that research on this question has been hampered by inadequate clarification of the criteria required for a proper test. We suggest what these criteria should be, and, for purposes of illustration, we evaluate representative tests of the lateralization--cognition hypothesis in light of these criteria. We conclude that studies that meet our criteria lend at least a modest measure of support for the hypothesis.