PUNISHMENT AND REWARD AS MOTIVES 



47 



TABLE 2 

 Percentages of Error for Daily Series of 10 Trials Each 



trials. When a perfect record for two days, i.e., 30 consecutive 

 correct choices, had been made, the problem was regarded as 

 learned. The table and curves show that the rats varied con- 

 siderably in their daily record, as well as in the time required 

 to learn the problem completely. Rat 1 (albino, group 1, 

 punished and rewarded) completed the association in 490 trials. 

 Rat 5 (pigmented eyes, of the same group), in 550 trials. Rat 

 3 (albino, group 2, punished) learned the problem in 550 trials, 

 but rat 7 (pigmented eyes, group 2) had not learned the prob- 

 lem in 620 trials, at which time the work had to be discon- 



