There were ten subjects in most of the experiments, and the marked differences in the individual records which were evident in the previous experiments did not exist here except in the case of A., for whom alone the time required to obtain the suppression exceeded the time of absence of the suppressed image.
In several experiments the subjects were unable to suppress the indicated image, which in five cases was the image at the center of a disc and in two cases the outer portion of the disc. Further, five failures were by one subject, D., and one each by A. and F. The statistical report here given includes only the results of the successful experiments. Forty-four of the one hundred and ninety-seven were completely successful, as the suppressed image did not return throughout the entire period. The following table shows the grouping of the experiments according to the recurrence of the suppressed image:
Returned 0 times, 44
" 1 "
26
" 2 "
18
" 3 "
25
" 4 "
16
" 5 "
16
" 6 to 10 "
28
" more than 10
times, 24
Total, 197
Seventy-three and three fifths per cent. of all the experiments have five or fewer returns of the suppressed images.
The subjects suppressed the image as soon as possible after each return, the average time taken to accomplish these later suppressions being 6.46 sec., while the average time of absence of the suppressed image was 32.14 sec.
Including the first efforts and the first absences of the suppressed image, the average time required to suppress the image was 7.60 sec., and the average time of absence of the suppressed image was 41.86 sec.
Arranging the subjects according to the average time they required to accomplish a suppression, we have the following order. J. and F. had more recurrences of the suppressed image than any of the other subjects.
J. 1.64 sec.
F. 2.40 "
C. 4.80 "
B. 4.98 "
I. 6.06 "
G. 11.15 "
H. 11.84 "
A. 16.05 "
K. 16.70 "
D. 25.80 "
Arranging them by the average absence of the suppressed image we have this order:
B. 251.08 sec
D. 193.89 "
H. 81.02 "
C. 62.07 "
I. 59.72 "
K. 31.83 "
J. 31.75 "
G. 19.47 "
A. 10.44 "
F. 10.09 "