Doctor Hamilton when told of this behavior, reported that several times monkeys have shown resentment toward him when they were having trouble in the experiment. I therefore feel fairly confident that I have not misinterpreted Sobke's behavior. When on July 22 I gave Sobke an opportunity to enter the apparatus, he refused, and it was impossible to lure him in with food. Two hours later, having waited meantime for his breakfast, he entered readily and worked steadily and persistently through his third series of trials, but in no one of these trials did he choose correctly. Neither on this day nor the following did he exhibit resentment while at work. He apparently had regained his affective poise and was able to attend as formerly to the task of locating his rewards.
During these first three series, although the ratio of right to wrong choices stood 0 to 10, there occurred a marked reduction in the number of trials in which aid was necessary as well as in the total number of choices, and on July 23 correct reactions began to appear. Improvement during the next hundred trials was steady and fairly rapid, and on July 31, a record of seven right to three wrong trials was obtained. This was surprising to the experimenter, as well as gratifying, since he was eager to have the animal complete this problem before work should have to be discontinued.
Everything went smoothly until August 2, when my assistant, who had been left in charge of the experimental work for a week, attempted to increase the number of trials per day to two series. Sobke apparently was not quite ready for this increase in the amount of his day's labor and refused to work at the end of the first series. In this series he did less well than on the previous day. The following day, August 3, unfortunately and contrary to the wishes of the experimenter, the laboratory was painted and there was necessarily considerable disturbance because of the presence of the workmen, and in addition, the pervasive odor of fresh paint. Sobke chose still less successfully on this date, and on August 4, he refused to work after the eighth trial. It is true that during these bad days the total number of choices steadily diminished while the successes, also, diminished, or at best, failed to increase. When on August 9, I returned to the laboratory to take charge, I found that Sobke was no longer trying to solve the problem as when I had gone away. His attitude had changed in that he had become indifferent, careless, and obviously discouraged with his task.
TABLE 7
Results for Sobke, P. rhesus, in Problem 4
========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+======== | No. | S.1 | S.2 | S.3 | S.4 | S.5 | S.6 | S.7 | S.8 | S.9 | S.10 | | | | | Ratio Date | of | | | 1.2.3.4 | | | 1.2.3.4.5 | | | 3.4.5.6 | | R | W | R | W | of | trials | 2.3.4 | 5.6.7.8.9 | 5.6.7 | 7.8.9 | 4.5.6.7.8 | 6.7.8.9 | 1.2.3 | 2.3.4.5.6 | 7.8.9 | 6.7.8 | | | | | R to W ————+—————-+———————+———————+———————+———————+———————+———————+———————+———————+———————+———————+—-+—-+—-+—-+———— | | | | | | | | | | | | | | | | July | | | {5.9.5.5 | {1.7.1.3 | {9.7.9.7 | | {1.9.3.1 | | {6.3.2.6 | | | | | | | 20 | 1- 10 | 2.4.2.4.3 | {5.9.5.6 | {1.7.1.7 | {7.9.7.9 | {8.4.8.4 | {9.2.9.3 | 3.1.3.2 | {3.6.3.2 | {9.3.4.3 | {8.6.6.8.6 | 0 |10 | 0 |10 | 0:10.00 | | | {5.8.7* | {1.7.4* | {7.7.8 | {4.6 | {9.1.5* | | {6.3.4* | {3.9.3.6 | {8.6.8.6.7 | | | | | | | | | | | | | | | | | | | | | | | | | | {7.9.7.7 | {4.8.5.5 | {1.4.3.2 | | | {3.9.3.8 | | | | | | 21 | 11- 20 | 2.3 | {5.6.5.5 | {1.2.7.1 | {7.9.7.7 | {8.4.8.4 | {8.9.1.9 | 3.1.2 | {6.2.3.2.6 | {4.3.3.5 | 6.7 | 0 |10 | 0 |10 | 0:10.00 | | | {9.5.5.7 | {7.3.7.4 | {9.7.8* | {5.4.6* | {1.9.5* | | {3.5.2.4 | {3.4.6* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {3.7.4.8 | | | | | | 22 | 21- 30 | 2.3 | 5.6.5.6.7 | 1.7.4 | {7.9.7 | 4.7.4.6 | {1.4.6.3 | 3.1.2 | 5.2.6.4 | {4.3.5.8 | 6.6.7 | 0 |10 | 0 |10 | 0:10.00 | | | | | {7.7.8 | | {2.7.5 | | | {3.7.6* | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {5.4.7.4 | | | | | | 23 | 31- 40 | 2.4.3 | 5.6.8.7 | 1.7.4 | {7.7.7.7 | 4.7.6 | 2.7.5 | 3.1.2 | 6.4 | {7.5.4.3 | 7 | 1 | 9 | 1 | 9 | 1: 9.00 | | | | | {7.7.8 | | | | | {7.3.6 | | | | | | | | | | | | | | | | | | | | | | 24 | 41- 50 | 3 | 5.6.7 | 1.6.4 | 7.7.7.8 | 4.7.6 | {2.7.6.4 | 3.2 | 6.5.4 | 5.3.8.6.6 | 7 | 1 | 9 | 1 | 9 | 1: 9.00 | | | | | | | {2.7.3.8 | | | | | | | | | | | | | | | | {9.6.5* | | | | | | | | | | | | | | | | | | | | | | | | | 26 | 51- 60 | 4.3 | 6.5.7 | 2.7.4 | 7.8 | 6 | {6.4.2.7 | 3.2 | {6.5.3.5.2 | 7.6 | 7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | {4.8.6.5 | | {6.5.6.4 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {4.7.3.7 | | | | | | | | | 27 | 61- 70 | 3 | 6.5.7 | 2.5.4 | 7.7.8 | 5.7.6 | {4.6.1.4 | 2 | 6.5.4 | 5.7.6 | 6.7 | 2 | 8 | 2 | 8 | 1: 4.00 | | | | | | | {7.3.5 | | | | | | | | | | | | | | | | | | | | | | | | | 28 | 71- 80 | 3 | 7 | 6.5.4 | 7.8 | 5.4.7.6 | 2.7.6.5 | 2 | 5.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 29 | 81- 90 | 3 | 6.5.7 | 2.4 | 7.7.8 | 5.4.6 | {2.7.7.6 | 2 | 4 | 5.4.7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {2.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 30 | 91-100 | 3 | 7 | 2.6.5.4 | 7.8 | 6 | 5 | 2 | 5.4 | 5.4.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 31 | 101-110 | 3 | 7 | 2.4 | 7.8 | 6 | 5 | 2 | 4 | 7.6 | 7 | 7 | 3 | 7 | 3 | 1: 0.43 August | | | | | | | | | | | | | | | | 2 | 111-120 | 3 | 7 | 6.5.7.6.4 | 7.8 | 6 | 4.2.7.6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 3 | 121-130 | 3 | 6.5.7 | 7.6.5.4 | 7.8 | 7.6 | 5 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 4 | 131-140 | 3 | 7 | 6.5.7.6.4 | 7.8 | 6 | {2.7.6.4 | 2 | 6.4 | 3.5.4.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 | | | | | | | {8.7.6.5 | | | | | | | | | | | {2.4.4.4 | | | | | | | | | | | | | | 5 | 141-150 | {2.4.4.2 | 6.5.7 | {2.7.6.7 | 8 | 7.6 | {2.8.7.6 | 3.2 | 6.4 | 7.6 | 8.7 | 1 | 9 | 1 | 9 | 1: 9.00 | | {4.3* | | {5.4 | | | {8.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 6 | 151-160 | 2.4.4.3 | 7 | 2.6.5.4 | 7.8 | 7.6 | 7.6.5 | 2 | 6.4 | 6 | 7 | 4 | 6 | | | | | | | | | | | | | | | | | | | | | {4.4.2.4 | | | | | | | | | | | | | | " | 161-170 | {4.2.4.2 | 7 | 6.5.4 | 7.8 | 7.6 | 7.6.5 | 3.2 | 5.4 | 7.6 | 7 | 2 | 8 | 6 |14 | 1: 2.33 | | {4.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 7 | 171-180 | 4.3 | 7 | 6.5.4 | 8 | 7.6 | 5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | | | | | | | | | | | | | | | | | | | " | 181-190 | {4.2.4.4 | 7 | 7.6.5.4 | 7.8 | 6 | 6.5 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 9 |11 | 1: 1.22 | | {2.4.3 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 9 | 191-200 | 3 | 7 | 5.4 | 8 | 8.7.6 | 6.5 | 2 | 6.5.4 | 7.6 | 8.7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | | | | | | | | | | 10 | 201-210 | 3 | 7 | 2.5.4 | 7.8 | 7.6 | {2.8.7.6 | 2 | 6.5.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {8.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 11 | 211-220 | 3 | 7 | 6.5.4 | 7.8 | 6 | {7.6.4.3 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 | | | | | | | {2.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 12 | 221-230 | 3 | 7 | 2.4 | 7.8 | 6 | 7.6.5 | 2 | 6.5.4 | 8.7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 19 | 231-240 | 3 | 7 | 2.4 | 7.8 | 6 | 5 | 2 | 6.4 | 8.7.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 | | | | | | | | | | | | | | | | 20 | 241-250 | 3 | 7 | 5.4 | 8 | 7.6 | {2.4.1.2.7 | 3.2 | 6.4 | 7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | | {8.7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 21 | 251-260 | 3 | 7 | 6.5.4 | 7.8 | {7.4.5.4 | {6.4.3.2 | 2 | 6.5.4 | 8.7.6 | 7 | 4 | 6 | 4 | 6 | 1: 1.50 | | | | | | {8.7.6 | {7.6.5 | | | | | | | | | | | | | | | | | | | | | | | | | 23 | 261-270 | 3 | 7 | 6.5.4 | 7.8 | 6 | 6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 24 | 271-280 | 3 | 7 | 6.4 | 7.8 | 7.6 | 2.5 | 2 | 4 | 7.4.3.8.7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 25 | 281-290 | 3 | 7 | 2.5.4 | 8 | 7.6 | 5 | 2 | 6.4 | 7.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 26 | 291-300 | 3 | 7 | 6.5.4 | 8 | 7.6 | 7.6.5 | 2 | 6.5.4 | 7.6 | 7 | 5 | 5 | 5 | 5 | 1: 1.00 27 | 301-310 | 3 | 7 | 2.6.5.4 | 8 | 7.6 | 5 | 2 | 6.5.4 | 7.5.4.9.8.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 28 | 311-320 | 3 | 7 | 2.5.4 | 8 | 6 | 9.8.7.5 | 2 | 3.4 | 8.6 | 7 | 6 | 4 | 6 | 4 | 1: 0.67 ========+===========+==============+==============+==============+==============+==============+==============+==============+==============+==============+==============+===+===+===+===+========
[Footnote *: Aided by experimenter.]
I immediately set about reinstating the former attitude by lessening the number of trials and the punishment, and by increasing the value of the reward, but my best efforts, continuing up to August 28, failed markedly to improve the condition. The number of correct choices did somewhat increase, but at no time did the animal attain the degree of success which he had achieved as early as July 31 in the eleventh series of trials.
During the last two weeks of experimentation, all possible efforts were put forth to discover the best combination of rewards and punishments. Punishment was varied from 0 to confinement of sixty seconds, and many kinds of food in different amounts were tried as rewards, but in spite of everything Sobke failed to improve markedly. From time to time, notably on August 12 and 21, he exhibited peculiarly strong resentment toward me and repeatedly attempted to attack me.
The outcome of my experiments with problem 4 is peculiarly interesting in that it indicates the importance of a favorable attitude toward the work and the extreme risk from disturbing or discouraging conditions. It seems not improbable that had the work progressed without change in experimenter, or method of procedure, and above all without the disturbance of the painting, Sobke might have solved problem 4 within a few days. This is by no means certain, however, for in problems 2 and 3 the ratio of right to wrong choices instead of increasing steadily increased very irregularly.