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V GRAF

Publications and source records attributed to V GRAF.

5 recordsLinked to original sources

AVERAGED BRAIN ACTIVITY FOLLOWING SACCADIC EYE MOVEMENT.

Since a change of stimulus is required to effect a visual response, and since saccadic eye movements change the locus of the retinal image, the hypothesis was developed that there should be a brain response following saccadic eye movement.- The hypothesis was tested experimentally by averaging the activities following successive saccadic eye movements. A response was found whose characteristics were dependent on illuminance of the stimulus.

Animals↗

FURTHER EXPERIMENTS ON PROBABILITY-MATCHING IN THE PIGEON.

In a discrete-trials, two-key choice situation, probability-learning by pigeons was studied under a variety of training conditions. Matching was found in simultaneous and in successive problems, but a spatial problem produced only maximizing. In the simultaneous problem, noncorrection produced maximizing, while correction produced matching. Guidance produced maximizing when the animals were required to earn each opportunity for choice by pecking a center key on FR-5, but matching when the center key was not used. In a discrete-trials one-key situation, with latency as the measure, frequency and probability of reinforcement were varied independently. Differences in probability produced differences in latency of response, but differences in frequency did not.

Animals↗

General activity as instrumental: application to avoidance training.

Some data on Sidman avoidance in the pigeon are presented to illustrate a technique of instrumental training which places minimal restriction upon the form of the reinforced response. The effect of a warning signal is demonstrated, and the course of discrimination-reversal is described.

Animals↗