Evaluating the Empirical Support for the Geschwind-Behan-Galaburda Model of Cerebral Lateralization

doi:10.1006/brcg.1994.1045

Brain and Cognition

Volume 26, Issue 2, November 1994, Pages 103-167

https://doi.org/10.1006/brcg.1994.1045 Get rights and content

Abstract

The Geschwind-Behan-Galaburda (GBG) model of cerebral lateralization provides 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 case of several key theoretical areas, the evidence that does exist is inconsistent 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 disorders finds a marginal overall association, and while three conditions (allergies, asthma, and ulcerative colitis) do show significant associations with left-handedness, two other conditions (myasthenia gravis and arthritis) show significant negative associations with left-handedness. Finally, a review of the origins of the neural crest, and its associations, suggests there is almost no empirical support for the GBG theoretical model in this area.

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Citation Excerpt :
Second, the Geschwind-Behan-Galaburda model (hereafter GBG) (Geschwind and Behan, 1982; Geschwind and Galaburda, 1985a, 1985b, 1985c, 1987) suggests that exposure to high levels of testosterone during gestation slows development of the left cerebral hemisphere, which can result in ‘anomalous dominance’, a term that is used to cover a range of phenomena including right hemisphere (or bilateral) speech representation, and left-handedness. Although the theory has at times been heavily criticised (see Bryden et al., 1994), many researchers have continued to test hypotheses derived from it (e.g., Beaton et al., 2011; Beaton et al., 2012; Kalmady et al., 2013; Stoyanov et al., 2011; Tran et al., 2014). Analogous with the sexual differentiation hypothesis, GBG theory predicts that high levels of foetal testosterone exposure will associate with left-handedness.
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Regular ArticleEvaluating the Empirical Support for the Geschwind-Behan-Galaburda Model of Cerebral Lateralization

Abstract

Regular Article
Evaluating the Empirical Support for the Geschwind-Behan-Galaburda Model of Cerebral Lateralization