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PubMedDate not supplied

[Motivation and reinforcement in the systemic mechanisms of behavior: the dynamic engrams of reinforcement].

Theoretical and experimental data are presented which give evidence that in systemic organization of behaviour motivation and reinforcement interact in separate brain neurons. It has been shown that the immunity mechanisms participate in motivation-reinforcement interaction. It is postulated that in the process of learning the reinforcement by means of feedback afferentation forms molecular engrams on the neuronal structures of action acceptor. Such engrams are built by DNA and protein synthesis in ribosomes. Later on these engrams can be activated by the dominant motivation.

Animals↗
PubMed1989

[Combination of self-reinforcement and external-reinforcement on matching-to-sample learning].

This study aimed at to investigate the combined effects of self-reinforcement (SR) and external-reinforcement (ER) on a matching-to-sample learning task. Four colored cards with four different marks (20, 10, 0, -10) were employed. Subjects of 27 college students were divided into three groups; SR, ER, and SR-ER groups, and they were requested to choose correct cards to score 20 marks in each trial. Subjects in SR and SR-ER groups were required to express their degrees of confidence by exhibiting either one, two or three chips of token accordingly. Following results were obtained. First, reinforcing powers were greater under both SR and SR-ER conditions than ER condition. Second, SR-ER group manifested a remarkably higher learning effect compared to SR group. This is interpreted as that the former established a sort of self-assurance due to ER contingency during this learning condition. Finally, the number of chips SR and SR-ER groups presented corresponded to the hitting rate of marks between n and n + 1 trials.

Adult↗
PubMed1965

THE EFFECT OF MULTIPLE S-DELTA PERIODS ON RESPONDING ON A FIXED-INTERVAL SCHEDULE. II. IN A PRIMATE.

A squirrel monkey was subjected to a fixed-interval pattern of reinforcement. During the course of each interval a bright white light was repeatedly presented. In the presence of the white light, a response was never immediately followed by food; the white light thus functioned as S(Delta). Responding was interrupted during the S(Delta) periods, but in the squirrel monkey as in the pigeon, these interruptions did not destroy the characteristic scalloped pattern of the cumulatively recorded responding through each interval.

Animals↗
PubMed1963

Some limitations on behavioral contrast and induction during successive discrimination.

A pigeon's rate of pecking on a red key, reinforced at a constant frequency, may be changed by increasing or decreasing the frequency of reinforcement of pecking on a successively presented green key. The changes in the rate of pecking on red, called interactions, are of two types: contrast, in which the changes in the rates of pecking on the two colors are in opposite directions; and, induction, in which the changes in the rates are in the same direction. In previous data, a change in the frequency of reinforcement associated with the green key produced a corresponding change in the rate of pecking the green key and an opposite change (contrast) in the rate of pecking on the red key. The present data suggest that the magnitude of contrast is very small if pecking on the red key is reinforced at a high enough frequency (about 40 reinforcements per hr in the present experiment). Also, given that interactions occur, induction rather than contrast may result from small changes in a low frequency of reinforcement associated with green.

Animals↗
PubMed1961

Time-out from positive reinforcement.

When an organism can itself impose extinction during fixed-ratio food reinforcement, the duration of the extinction period is a function of the number of responses required for reinforcement. Typically, the subject imposes extinction at the start of the usual fixed-ratio run.

Conditioning, Operant↗
PubMed2004

Cognitive and motor effects of dopaminergic medication withdrawal in Parkinson's disease.

AIMS: Recent evidence points towards dissociable effects of dopaminergic medication on motor function and cognitive function mediated by different fronto-striatal neural circuits. This study aimed to clarify the role of dopaminergic medication in spatial working memory, and reinforcement-based associative learning in relation to clinical changes in motor function in early Parkinson's disease (PD). METHOD: We tested 14 patients with mild to moderate PD on and off dopaminergic medication, on a spatial delayed-response working memory task, and on spatial and non-spatial (visual) trial-and-error learning tasks based on reinforcement, carefully matched for motor requirements. In addition, we explored relationships between the effects of withdrawal on motor symptom expression and performance on the cognitive tasks. RESULTS: Withdrawal from dopaminergic medication significantly exacerbated motor symptoms. This was related to spatial learning, but not visual learning, or delayed response accuracy. Moreover, medication withdrawal led to dissociable effects of response latency on the spatial learning and spatial delayed response tasks, with patients becoming faster after spatial learning, but relatively slower on the delayed response task. These changes in response latency were unrelated to motor symptom impairment. CONCLUSION: Our findings suggest dissociable effects of dopamine medication withdrawal on cognitive processes putatively mediated by dorsal and ventral striatal regions.

Aged↗
PubMedDate not supplied

[The capacity of ants for multiple alterations in the maze habit].

Ability was shown of ants Myrmica rubra to multiple reconstructions of the habit elaborated in symmetrical multialternative maze under motivation of care for the progeny (transportation of breed of the own species). Reconstruction consisted in the change of reinforcement location on the left or right aim spot. The ants showed the ability to carry out the series of eight reconstructions during one-two days. An improvement took place of the fulfillment of the last reconstructions in comparison with the first ones. Peculiarities of learning and reconstructions were found in two groups of animals differing by conditions of learning: at reinforcement on both ain spors or on one of them. The results obtained are considered as indices of high plasticity of the behaviour of ants of the studied species.

Animals↗