Cortical Activity preceding Speech: Semantic Specificity


RELIABLE, non-random changes in the electrical activity of the human brain, designated “cortical command potentials”, have been observed preceding voluntary hand and foot movements1, finger pressing2 and speech3. Command potentials which have been detected to date have shown relatively undifferentiated uniphasic or biphasic waveforms over the contralateral motor area; no specificity with respect to the voluntary activity time-locked to these potentials has been reported.

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  1. 1

    Gilden, L., Vaughan, jun., H. G., and Costa, L. D., EEG Clin. Neurophysiol., 20, 433 (1966).

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    Vazquez, A. J., and Toman, J. E. P., EEG Clin. Neurophysiol., 21, 381 (1966).

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    Ertl, J., and Schafer, E. W. P., Life Sciences, 6, 473 (1967).

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SCHAFER, E. Cortical Activity preceding Speech: Semantic Specificity. Nature 216, 1338–1339 (1967).

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