Abstract: | Murphy, K., D. R. Corfield, A. Guz, G. R. Fink, R. J. S. Wise, J. Harrison, and L. Adams. Cerebral areas associated withmotor control of speech in humans. J. Appl.Physiol. 83(5): 1438-1447, 1997. We have definedareas in the brain activated during speaking, utilizing positronemission tomography. Six normal subjects continuously repeated thephrase "Buy Bobby a poppy" (requiring minimal languageprocessing) in four ways: A) spoken aloud, B) mouthed silently,C) without articulation, andD) thought silently. Statisticalcomparison of images from conditions Awith C andB withD highlighted areas associated witharticulation alone, because control of breathing for speech wascontrolled for; we found bilateral activations in sensorimotor cortexand cerebellum with right-sided activation in the thalamus/caudate nucleus. Contrasting images from conditionsA with B andC with D highlighted areas associated withthe control of breathing for speech, vocalization, and hearing, becausearticulation was controlled for; we found bilateral activations insensorimotor and motor cortex, close to but distinct from theactivations in the preceding contrast, together with activations inthalamus, cerebellum, and supplementary motor area. In neithersubtraction was there activation in Broca's area. These resultsemphasize the bilaterality of the cerebral control of "speaking"without language processing. |