Page:The Harveian Oration,1902.djvu/59

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adjoining region. But the careful experiments and weighty considerations advanced by Francois Franck[1] render it, I think, probable that all the cardiac and vascular effects that occur are merely the correlated concomitants of the functional activity of the motor centres, excited in a more or less obvious epileptic manner; or that the cerebral hemispheres are only the point of departure of stimuli which influence the cardiac and vaso-motor centres of the medulla oblongata in precisely the same way as those which originate in the periphery. The results are inconstant—sometimes acceleration, sometimes inhibition; they cannot be foretold; they do not vary with the point of stimulation; they have none of the features of the contra-lateral manifestations so characteristic of stimulation of the motor centres; and there is no good ground for assuming that there are any definite areas controlling respectively acceleration, inhibition, vaso-constriction, or vaso-dilatation. It is, indeed, probable that many of the reactions on the heart and blood-vessels which have been described as resulting from cortical excitation

  1. Les Fonciions Matrices du Cervean, 1887.