EVALUATING THE EMPIRICAL SUPPORT FOR THE GESCHWIND-BEHAN-GALABURDA MODEL OF CEREBRAL LATERALIZATION

The Geschwind-Behan-Galaburda (GBG) model of cerebral lateralization p rovides a complex but testable theory of the origins and associates of cerebral lateralization. An overall evaluation of the model suggests that it is not well supported by empirical evidence and that in the ca se of several key theoretical areas, the evidence that does exist is i nconsistent with the theory. In particular: the concept of ''anomalous dominance'' is shown to be theoretically and methodologically flawed; a meta-analysis of the relationship between handedness and immune dis orders finds a marginal overall association, and while three condition s (allergies, asthma, and ulcerative colitis) do show significant asso ciations with left-handedness, two other conditions (myasthenia gravis and arthritis) show significant negative associations with left-hande dness. Finally, a review of the origins of the neural crest, and its a ssociations, suggests there is almost no empirical support for the GBG theoretical model in this area. (C) 1994 Academic Press, Inc.