Page:American Journal of Psychology Volume 21.djvu/547

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VOLUNTARY MOVEMENT
535

for writing the list of ten words or forty letters, R's averages are based upon 50 records; E, C and D's upon 30 records each. The numbers express fifths of a second.

Eyes open

E. 28.2
R. 35-6
C. 47-8
D. 52.5

Eyes closed

29.7
39.7
54.7
70.2

D and C show the greatest differences. D practiced with eyes upon the cardboard in open-eye practice while C did not. Whatever the reason for these differences, it is clear that open eyes facilitated the writing even when the cardboard and bulbs were not regarded. It is possible that these time differences are due to differences in liability to distraction. This latter difference shows itself in the difficulty with which eye-closed practice records were obtained. Not only were mistakes more liable, but there were actual "break downs" when the attempt was made to obtain the eye-closed records, due to more pronounced consciousness of the rotating drum, etc. Such broken records were of course not used in obtaining the above averages. It is possible that the eye has a steadying effect upon voluntary movement, because of the original close connection this sense organ sustains with all our voluntary activities involving objects or extra-bodily space. It is possible, too, that vision aids by holding the external circumstances of the experiment in consciousness, at least in a peripheral way, and thus by association helps to maintain the "set." At any rate the "set" of consciousness here described was more readily maintained in eyeopen than in eye- closed practice.

To summarize, The automatization of a highly voluntary movement like the one here studied, involves the three following stages:

1st. A period of perceptual attention to details in which vision plays the leading role, the muscular sensations being only marginal, unless abnormal conditions, subjective or objective, force them into the focus of consciousness.

2nd. A transitional period, or period of adaptation, which is characterized by three things: (a) A process of elimination of perceptual data and, in instances if not in all cases, the substitution of memory imagery, for a longer or shorter period, for the eliminated perceptual data, (b) A gradual lessening of the intensity of attention and of general psychophysical tension, (c) The development of an organized "set" of consciousness in which the details no longer require attention in themselves but only as parts of a complex whole, the elements