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T VERHAVE

Publications and source records attributed to T VERHAVE.

11 recordsLinked to original sources
PubMed1963

TOWARDS AN EMPIRICAL CALCULUS OF REINFORCEMENT VALUE.

Only one of two keys reinforces the subject with food. This key can assume one of two colors, each associated with a different fixed-ratio schedule for obtaining reinforcement. The function of the second key is to permit the animal to switch from the long schedule to the short schedule. If the difference between the ratio schedules is large enough, a preference for the shorter schedule is demonstrable. A quantitative index of preference is obtained as follows: each time the animal switches to the shorter schedule, the number of pecks required to produce the next switch is increased. As the "ante" on the switching key increases, the effective difference between the two ratio schedules decreases. After each food reinforcement, when the bird is exposed to the choice-situation, it takes longer before the bird switches again. This is used to "titrate" the bird's preference. If it does not switch within x sec, the progressively increasing ratio schedule of the switching key is decreased. A specific value, in terms of a rather specific number of responses the bird settles at on the choice key, is obtained. This equilibrium is employed as a dependent variable. Several variables of which it is a function are explored.

Animals↗
PubMed1962

The functional properties of a time out from an avoidance schedule.

Investigations are reported of some of the discriminative (cue) and reinforcing properties of stimuli (TO(av)) correlated with the discontinuation of a free-operant avoidance schedule. After several unsuccessful initial attempts to demonstrate the positively reinforcing effect of TO(av), a special technique was developed. The subjects were trained by means of a free-operant avoidance procedure to press a lever and postpone electric shock; by pressing a second lever, they could produce a cue correlated with the TO(av) period. The importance of a distinct cue correlated with TO(av) was demonstrated in experiments in which this signal was eliminated from the procedure. The reinforcing function of the TO(av) period was explored by showing its effectiveness under various schedules of reinforcement. Other observations were made concerning the course of extinction of both TO(av)-producing responses and avoidance behavior. In further experiments in which TO(av) was used as a reinforcer, the TO(av) behavior was also brought under separate stimulus control. The development of the various discriminations involved in the resulting performance were described.

Conditioning, Operant↗
PubMed1961

Labelling device.

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Equipment and Supplies↗