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W C STEBBINS

Publications and source records attributed to W C STEBBINS.

13 recordsLinked to original sources

CARDIOVASCULAR CONCOMITANTS OF THE CONDITIONED EMOTIONAL RESPONSE IN THE MONKEY.

Flow transducers were surgically implanted on the terminal aorta of five monkeys. A classical conditioning procedure, in which a light preceded a brief shock, was superimposed upon a variable-interval schedule of food reinforcement for key pressing (three monkeys) and alternated with an avoidanceschedule of shock reinforcement for key pressing (two monkeys). Suppression of the rate of the response of key pressing and sizable increase in blood flow and heart rate during the light were obtained for all animals.

Animals↗

NOTE OF CHANGES IN RESPONSE LATENCY FOLLOWING DISCRIMINATION TRAINING IN THE MONKEY.

Two monkeys were trained to press and hold down a telegraph key in the presence of a red light. Subsequent release of the key in response to a white cross superimposed on the red background was followed by reinforcement. Key release in response to a white circle on the red background was never reinforced. Latencies for the key release response to the reinforced stimulus (cross) were considerably shorter and less variable than those to the unreinforced stimulus (circle).

Animals↗

REACTION TIME AS A FUNCTION OF STIMULUS INTENSITY FOR THE MONKEY.

Monkeys were trained to release a telegraph key in response to a visual or auditory stimulus. The latency of the key release response was measured for different stimulus intensities. In general, the relation between latency and intensity is inverse and exponential with greater variability of latency at the lower intensities. Some preliminary data involving differential reinforcement of short latencies are presented.

Animals↗

Response latency as a function of reinforcement schedule.

Four Ss were trained to press and hold down a telegraph key in the presence of a light. Subsequent release of the key during a tone was followed by water reinforcement. The schedule of reinforcement for key release was varied, and its effects on the latency (RT) of key release to the tone were studied. Both median RT and variability of RT were found to be inversely related to frequency of reinforcement as determined by the schedule.

Learning↗

Response latency as a function of amount of reinforcement.

Food-deprived rats were trained to press and hold down a telegraph key in the presence of a light. Subsequent release of the key during a tone was followed by 0.15 ml of a 20-percent sucrose solution as reinforcement. The Ss were subsequently shifted to a 0-percent and to a 5-percent solution from the 20-percent base line. The median RT and the variability of RT increased markedly as a result of the shift to the lower sucrose concentrations. For all Ss, the change in median and variability was greater for the shift to the 0-percent solution than for the shift to the 5-percent solution. It is probable that median RT and variability of RT are inversely related to amount of reinforcement.

Animals↗