Page:American Journal of Psychology Volume 21.djvu/561

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VOLUNTARY MOVEMENT
549

out serious disturbances. If with eyes closed, the patient is asked a question she merely moves her lips in reply but upon opening her eyes declares she answered the question aloud. If her ears are closed and she is handed a written question she again merely moves her lips in reply, declaring when her ears are opened that she replied aloud. If she is requested to open and close her hands she accomplishes the movements by fixating the right hand. But if the right hand is placed outside the narrow field of vision the movements cease. Two interesting facts appear in this case: (a) when the sense processes are reduced to a certain minimum the movements called for, if executed at all, are reduced to a certain minimum of intensity, (b) In the two hand movements the left hand is controlled by means of the "resident" sensations while the right hand is controlled by means of vision or "remote" sense processes. In other words, either resident or remote sensation is essential for the control of each arm, the coordination (apparently) taking place when the one is controlled by "resident" and the other by "remote" processes.

Pick also cites the cases of Duchenne who observed three patients with total loss of sensibility on one side. Duchenne found that they were unable to move the anaesthetic members without the aid of vision. Both Pick and Duchenne explain their cases wholly in terms of attention. This explanation may be criticised on the following grounds: (i) Attention is not a psychic entity, as these authors appear to imply, but only a state of psychic processes. (2) As a state of psychic processes attention is, to quote Pillsbury, merely ' 'an increase in the clearness of one idea or group of ideas at the expense of others. " (Attention, p. n.) (3) To attend there must be something to attend to, which is what is wanting to the ansesthetic. That attention is an important factor in all forms of voluntary movement would probably be conceded by every competent observer, but that attention cannot create sensations and ideas but only render them conscious, or better, more clearly conscious, must be conceded with equal readiness. And what the facts show in these cases is primarily a loss of sensations and ideas normally functional in voluntary movement.

Bleuler also rejects the explanation in terms of attention on the ground that his case showed no marked disturbances of attention when getting sensations. In place of this explanation. Bleuler offers the following. He points out that we never take notice of the particular muscles concerned in making movements. "Unser bewusster Wille innervirt also nicht bestimmte Muskeln, sondern er fiihrt mit den Gliedern bestimmte Locomotionen oder bestimmte Thätigkeiten aus."