摘要:

The behavior of pigeons on six geometrically spaced fixed‐interval schedules ranging from 16 to 512 sec is described as a two‐state process. In the first state, which begins immediately after reinforcement, response rate is low and constant. At some variable time after reinforcement there is an abrupt transition to a high and approximately constant rate. The point of rapid transition occurs, on the average, at about two‐thirds of the way through the interval. Response rate in the second state is an increasing, negatively accelerated function of rate of reinforcement in the second

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-677

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Experiments with pigeons and rats showed that: (1) When a brief blackout was presented in lieu of reinforcement at the end of 25% of intervals on a fixed‐interval 2‐min schedule, response rate was reliably and persistently higher during the following 2‐min intervals (omission effect). This effect was largely due to a decrease in time to first response after reinforcement omission. (2) When blackout duration was varied, within sessions, over the range 2 to 32 sec, time to first response was inversely related to the duration of the preceding blackout, for pigeons, and for rats during the first few sessions after the transition from FI 2‐min to FI 2‐min with reinforcement omission. Post‐blackout pause was independent of blackout duration for rats at asymptote. These results were interpreted in terms of differential depressive effects of reinforcement and blackout on subsequent

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-689

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

In three experiments, human subjects were trained on a five‐component multiple schedule with different fixed intervals of monetary reinforcement scheduled in the different components. Subjects uninstructed about the fixed‐interval schedules manifested high and generally equivalent rates regardless of the particular component. By comparison, subjects given instructions about the schedules showed orderly progressions of rates and temporal patterning as a function of the interreinforcement intervals, particularly when feedback about reinforcement was delivered but also when reinforcement‐feedback was withheld. Administration of the instructions‐reinforcement combination to subjects who had already developed poorly differentiated behavior, however, did not make their behavior substantially better differentiated. When cost was imposed for responding, both instructed and uninstructed subjects showed low and differentiated rates regardless of their prior histories. It was concluded that instructions can have major influences on the establishment and maintenance of human operant b

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-701

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Key‐pecking behavior in the pigeon was maintained under second‐order schedules in which food was presented after a variable number of 2‐min fixed‐interval components were completed. When either the same stimulus (Exp. I) or different stimuli (Exp. II) appeared on the key during consecutive components, and a stimulus that was occasionally paired with food was presented briefly at completion of each component, (1) patterns of positively accelerated responding were maintained during the components, and, (2) mean response rates were generally as high during the initial components of a sequence as during the later components. In both experiments, when the food‐paired stimulus was omitted and either no stimulus or a stimulus never paired with food was presented at completion of each component, mean rates of responding increased, but patterns of positively accelerated responding were not maintained during individual components. When a food‐paired stimulus was not presented at completion of the components, mean response rates in Exp. I were low during the initial components of a sequence and gradually increased during subsequent components; in Exp. II mean response rates were variable, and pauses and abrupt changes in response rates w

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-713

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Pigeons' responses in the presence of two concurrently available (initial‐link) stimuli produced one of two different (terminal‐link) stimuli. The rate of reinforcement in the presence of one terminal‐link stimulus was three times that of the other. Three different pairs of identical but independent variable‐interval schedules controlled entry into the terminal links. When the intermediate pair was in effect, the pigeons distributed their (choice) responses in the presence of the concurrently available stimuli of the initial links in the same proportion as reinforcements were distributed in the mutually exclusive terminal links. This finding was consistent with those of earlier studies. When either the pair of larger or smaller variable‐interval schedules was in effect, however, proportions of choice responses did not match proportions of reinforcements. In addition, matching was not obtained when entry into the terminal links was controlled by unequal variable‐interval schedules. A formulation consistent with extant data states that choice behavior is dependent upon the amount of reduction in the expected time to primary reinforcement, as signified by entry into one terminal link, relative to the amount of reduction in expected time to reinforcement signified by entry into the other te

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-723

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

In an analysis of interactions between concurrent performances, variable‐interval reinforcement was scheduled, in various sequences, for both keys, for only one key, or for neither key of a two‐key pigeon chamber. With changeover delays of 0.5 or 1.0 sec, and with each key's reinforcements discriminated on the basis of key‐correlated feeder stimuli, reinforcement of pecks on one key reduced the pecking maintained by reinforcement on the other key. The decrease in pecking early after reinforcement was discontinued on one key was not substantially affected by whether pecks on the other key were reinforced, but after reinforcement was discontinued on both keys, reinstatement of reinforcement for one key sometimes produced transient increases in pecking on the other key. Correlating the availability of right‐key reinforcements with a stimulus, which maintained right‐key reinforcement while reducing right‐key pecking to negligible levels, demonstrated that these interactions depended on concurrent reinforcement, not concurrent responding. Thus, reinforcement of a response, but not necessarily the occurrence of the response, inhibits other reinforced responses. Compared with accounts in terms of excitatory effects of extinction, often invoked in treatments of behavioral contrast, this inhibitory account has the advantage of dealing only with observed dimensions

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-731

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Neurological patients were subjects in delayed visual matching‐to‐sample. The sample and choice stimuli were ellipses of varying size. By measuring the difference in size between the sample on a given trial and the ellipse the subject chose on that trial, gradients of differences between samples and choice stimuli could be plotted. These difference gradients broadened with increasing delays. Sharp gradients were controlled by the samples. Flat gradients were controlled by features of the choice display, independently of the samples. Intermediate gradients reflected combined control by the samples and by the choice displ

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-745

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-758

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Pigeons were trained to key‐peck for food, first with single‐stimulus training and then with successive discrimination (multiple schedule) training. In the multiple schedule, two different wavelengths were each correlated with equally frequent variable‐interval reinforcement but different durations (6 secvs.2 sec) of access to grain. For some birds, the different durations of feeding cycle were cued by different intensities of the food hopper light. For some of these “cued” birds, single‐stimulus training had been carried out with 6‐sec feedings and when multiple‐schedule training was introduced, the novel stimulus was correlated with 2‐sec feedings. For the others, 2‐sec feedings were originally used, and the novel stimulus was then present during the 6‐sec reinforcement duration. The cueing procedure enhanced discrimination performance, and was necessary for the consistent production of a peak shift. In addition, the condition in which original training had been carried out with 6‐sec feedings, and thus reinforcement duration was reduced in the presence of the novel stimulus, led

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-759

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

To learn whether prior discrimination training based on one stimulus would block learning about a subsequently added stimulus, rats were first trained to press a bar on a variable‐interval schedule of food reinforcement. Occasional stimuli were presented during which no reinforcement was available. Responding became suppressed in the presence of these stimuli. Stimuli could be noise, light, or a compound of noise plus light. A group trained with noise in Phase 1, then trained with the compound in Phase 2, showed less suppression to light in a subsequent test than a group that had the same compound training in Phase 2 but only variable‐interval training in Phase 1. This showed that prior training with noise blocked the development of control by light during compound training. Two further groups showed that noise training following compound training did not have the same effect on control by li

ISSN:0022-5002    

DOI:10.1901/jeab.1969.12-767

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY