A cognitive probability model for learning

A quantitative model for the behavior of albino rats in choice-making situations is presented. The model, which is based upon a cognitive conceptualization of the learning process, is shown to yield predictions which are equivalent to those produced by the linear operator stochastic models at the asymptotic limit but which differ from these during early trials in the learning situation.     

Varying temporal placement of an added stimulus in a fixed-interval schedule

One paradigm for exploring stimulus effects on behavior is defined for steady state experiments. The paradigm is illustrated by a 60-sec fixed-interval reinforcement schedule wherein a 6-sec light is introduced into each interval. The temporal relation of this stimulus to the reinforcer is the independent variable that is systematically explored. Two experiments studied this temporal relation under two parametric conditions: (a) when the 6-sec light occurs once in each 60-sec interval, (b) when the 6-sec light occurs twice in each interval, the second time always during the 6 sec immediately preceding the reinforcer. Functions are presented showing the effect of the 6-sec light on responding at all points in the fixed-interval.     

Stimulus factors in aversive controls: conditioned suppression after equal training to two stimuli

Pigeons trained to peck a key for food were periodically presented with tones ending with electrical shock until tone presentation consistently suppressed ongoing pecks. Shock was then discontinued and gradients of stimulus generalization were assessed by presenting tones with frequencies above, below, and at the frequencies of those used to develop conditioned suppression. When the training tones had frequencies at 670 and 1500 cps, resulting gradients were bi-modal with peak suppression at 670 and 1500 cps. Of the other test tones, 1000 cps produced the most suppression. When the training tones had frequencies at 450 and 2250 cps, bi-modal gradients were again obtained with peak suppression to the 450 and 2250 cps tones. Of the other test tones, 1000 cps produced the least suppression. These results support the hypothesis that generalized response tendencies summate.     

The use of rats as discriminative stimuli

A FREE OPERANT PROCEDURE WAS USED TO DETERMINE WHETHER OR NOT ONE RAT COULD DISCRIMINATE: (1) between the presence and absence of a second rat, and (2) between two other rats of the same species and sex. The subjects were four male Wistar rats. The discriminatory response was a bar press and food was used as reinforcement during training. Although there were wide individual differences in rate of learning, all subjects learned to make both discriminations.     

Changes in Academic Performance in the Junior High School

This study was designed to determine the relationships between changes in academic performance and intellective and non-intellective factors. Seventh grade students attending five junior high schools, who had attended selected elementary schools, were tested with the Personal Values Inventory (PVI), a test of academic motivation, shortly after the first seventh-grade marking period. School marks at that marking period and those received the previous year were procured from a self-report included in the PVI. All students had taken the California Achievement Test Battery and Mental Maturity Test as well as the Scholastic Testing Service Work-Study Skills Test in the sixth grade. Factor analysis identified four factors in both boys and girls: intelligence-achievement, academic motivation, academic plans, and youth-culture involvement. While intelligence was found to be mainly unrelated to the criterion, the non-intellective factors, especially academic motivation, bore significant relationships to the changed performance.