In an additional series of experiments with five of the same subjects (B., G., H., I. and K.), the object was moved during the five seconds of exposure either right, left, up or down, a distance of about six to eight inches, and back again. In this way the subject was supplied with further material of a pure memory type and it was believed that some addition to our knowledge of the nature of the control of the image might thus be made by securing data contrasting the construction and the more purely reminiscent work of the imagination.
The question proposed is as follows: Does the fact that a certain movement of an object was presented to the optical perception give an advantage in time, or ease, to the mental recall of that object as so moving, over its recall as moving in other directions? The subjective experiences during such recalls may be expected to throw light upon the matter.
The subject, with closed eyes, was requested to move the mental image of the object in the four directions indicated above, returning it after each movement to its original position, and the time of each movement was recorded and, as well, the report of the subject with regard to his subjective experiences. There were sixteen hundred movements in all, eight hundred away from the original position of the image (two hundred in each of the four directions mentioned above) and eight hundred in returning to the original position.
Besides these experiments, other movements of the object during exposure were made, such as inversion, rotation, change from the vertical to the horizontal position and vice versa, rolling, oblique movements and the subjective phenomena were recorded when the subject had repeated with the image the designated movements. In all the experiments the objects were moved by the hand of the conductor of the experiment.
Table VII. gives the time record in seconds of these experiments for each subject under each of the four variations: Movement of the object to right, left, up, down.
MOVEMENTS OF A SINGLE IMAGE, THE
OBJECT HAVING BEEN MOVED DURING THE
TIME OF OPTICAL STIMULATION. AVERAGE TIME IN SECONDS. TEN MOVEMENTS IN
EACH DIRECTION FOR EACH SUBJECT.
a. Object moved to right.
Subject R. Return L. Return Up Return Down Return Aver. B. 0.57 0.75 0.62 0.60 0.64 0.35 0.42 0.37 0.62 0.44 G. 0.55 0.60 0.55 0.57 0.57 0.27 0.25 0.27 0.25 0.26 H. 6.95 6.90 6.47 6.40 6.65 5.40 5.55 4.50 5.00 5.11 I. 2.05 2.10 2.05 2.22 2.10 1.15 1.35 1.32 1.57 1.35 K. 2.35 2.97 2.42 2.62 2.59 1.17 1.20 1.17 1.55 1.28 Ave. 2.49 2.66 2.02 2.48 2.52 1.67 1.75 1.53 1.80 1.69
Ave. to right, 2.49
Ave. of other movements, 2.52
Grand average, 2.10