Human Brain: Left-Right Asymmetries in Temporal Speech Region
At the time Walter Levitsky and I published this paper the prevailing view was that there were no significant anatomical asymmetries between the hemispheres and that the cause of cerebral dominance would have to be sought in purely physiological or in subtle anatomical differences between the two sides. Since the publication of this paper the results reported here have been replicated by several groups. Juhn Wada’s report at the International Neurological Congress in 1969 not only confirmed our findings in adults, but also reported the presence of these asymmetries in the brains of fetuses and new-borns. More recently Teszner (1972) in Paris and Witelson and Pallie (1973) in Canada have added further confirmations. The statistics in all these series have been very close in value. Dr. William Sheremata and I have as yet unpublished data showing a correlation between the larger left temporal plane and the longer left occipital horn described by McRae et at. (1968). As a result of this correlation it will be possible to make a rough prediction as to the presence of anatomical asymmetry on the basis of pneumoencephalographic findings. The development of elaborate computerized scanning devices should make it possible to determine the size of the left occipital horn non-invasively. In fact it is possible that by suitable programming it will be possible to determine directly the size of the temporal plane on the two sides.
KeywordsSylvian Fissure Planum Temporale Cerebral Dominance Aphasic Patient Anatomical Asymmetry
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- McRae, D. L., Branch, C. L., and Milner, B., ‘The Occipital Horns and Cerebral Dominance’. Neurology 18 (1968) 95–98.Google Scholar
- Teszner, D., Élude cmatomique de l’asymétrie droite-gauche du planum temporale sur 100 cerveaux d’adultes. Thèse pour le Doctorat en Médecine. Université de Paris, 1972.Google Scholar
- Bonin, G.. von. in Inter hemispheric Relations and Cerebral Dominance (ed by V. Mountcastle ), Johns Hopkins Press, Baltimore. Md.. 1962, p. 1.Google Scholar
- Connolly, C. J., External Morphology of the Primare Brain, Thomas, Springfield, I11., 1950, pp, 144 and 205.Google Scholar
- Flechsig, P., Neurol. Zentralbl. 27 (1908) 2, 50.Google Scholar
- Meyer, A., in Collected Papers of Adolf Meyer (ed. by E. Winters), Vol. 1, Johns Hopkins Press, Baltimore, Md., 1950, p. 358.Google Scholar
- Penfield, W. and Roberts. L., Speech and Brain-Mechanisms, Princeton Univ. Press, Princeton, N. J., 1959, p. 130.Google Scholar
- Pfeifer, R. A., in Handbuch der Neurologie (ed. by O. Bumke and O. Foerster), Vol. 6, Springer, Berlin. 1936, p. 533.Google Scholar
- Zangwill, O., in Handbook of Physiology, Sect. I. ‘Neurophysiology’ Vol. 3, Williams and Wilkins, Baltimore, Md., 1960, p. 1709.Google Scholar