摘要:

Pigeons were trained to discriminate the duration of a stimulus. One response in a psychophysical choice situation was reinforced, given the immediately prior presentation of a stimulus duration in one class of durations called short durations, and the other response was reinforced given the immediately prior presentation of a stimulus duration in a second class called long durations. Durations of equal logarithmic difference from the cutoff, whether in the short or long class, yielded equal accuracy. Accuracy was a function not only of the properties of the stimuli to be discriminated, but also of the experimental contingencies used. Accuracy was greater in variable‐ratio than in fixed‐ratio schedules of reinforcement of the discriminative responses, and was lower at the beginning than later in individual fixed ratios. Proportion of short or long responses (response bias) was affected by sequential dependencies among long and short durations and was effectively controlled through the use of asymmetric reinforcement and fixed‐ratio continge

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-223

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

Terrace suggested that the peak shift in stimulus generalization occurs because the training stimulus not correlated with reinforcement has become aversive. This hypothesis is plausible in the light of instances where the peak shift is obtained compared with those where it fails to appear. The present experiment attempted to test implications of this hypothesis. Two groups of pigeons learned the same two‐stimulus discrimination between colors by different training methods in a free‐operant situation. When the discrimination was trained with many errors, a large peak shift was obtained in a subsequent generalization test of wavelength; after discrimination training with few errors, a negligible shift was observed. Half of each group then received noncontingent aversive shock during presentations of the stimulus not correlated with reinforcement in continued discrimination training. After this treatment, the errorless‐shock subgroup showed a large peak shift and the error‐shock subgroup tended to show a larger shift than before. Nonshocked control groups showed little change in the peak shift. It was concluded that pairing aversive shock with a stimulus not correlated with reinforcement is sufficient to produce or enhance a peak shift. In their effect on the peak shift, aversive shock and large amounts of nonreinforced responding appear to be equ

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-239

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

Interresponse time distributions of the terminal rate under fixed‐interval and fixed‐ratio schedules were examined, using data from three rats in each case. By means of a sequential analysis, the overall interresponse time distributions were separated into orderly components. Consideration of the component distributions suggested that multiple determinants of rate act in succession, not simultaneously, and that probability of reinforcement has an important effect on the probability of occurrence of interresponse ti

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-251

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-259

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

In a two‐link, concurrent‐chain schedule, pigeons' pecks on each key during the initial link occasionally produced a terminal link, during which only that key was operative. Responses in the terminal link were reinforced with food on either fixed‐interval or variable‐interval schedules. In one experiment, relative amount of responding in the initial link equaled the relative harmonic rate of reinforcement in the terminal links. In a second experiment, the selection of interreinforcement intervals in variable‐interval schedules in the terminal links was such that rates of reinforcement based on the harmonic or on the arithmetic means of the interreinforcement intervals predicted opposite preferences in the initial links. The observed preference was consistent with that predicted by the harmonic rather than by the arithmetic rates of rein

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-263

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

In a multiple schedule, exteroceptive stimuli change when the reinforcement schedule is changed. Each performance in a multiple schedule may be considered concurrent with other behavior. Accordingly, two variable‐interval schedules of reinforcement were arranged in a multiple schedule, and a third, common variable‐interval schedule was programmed concurrently with each of the first two. A quantitative statement was derived that relates as a ratio the response rates for the first two (multiple) variable‐interval schedules. The value of the ratio depends on the rates of reinforcement provided by those schedules and the reinforcement rate provided by the common variable‐interval schedule. The following implications of the expression were evaluated in an experiment with pigeons: (a) if the reinforcement rates for the multiple variable‐interval schedules are equal, then the ratio of response rates is unity at all reinforcement rates of the common schedule; (b) if the reinforcement rates for the multiple schedules are unequal, then the ratio of response rates increases as the reinforcement rate provided by the common schedule increases; (c) the limit of the ratio is equal to the ratio of the reinforcement rates. Satisfactory confirmation was obtained for the first two implications, but the third was left

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-271

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

This experiment investigated the effect of several punishment intensities on two responses maintained by contrasting rates of reinforcement. The responses were concurrently reinforced according to two different variable‐interval schedules. Because these schedules were independent of one another and programmed different rates of reinforcement, the two responses occurred at dissimilar rates. When responses were simultaneously suppressed by punishment, both rates were reduced proportionately until suppression was virtually complete. In other words, the per cent suppression resulting from punishment was independent of the rate at which the response was reinforced. Phenomena found in single‐response studies were duplicated here. Responding tended to increase both within and between punishment sessions at mild and moderate punishment intensities. Cessation of punishment led to a “compensatory” overshooting beyond the prepunished respon

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-285

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

Six rats with electrodes chronically implanted in septal or hypothalamic sites were tested for intracranial reinforcement on a progressive fixed‐ratio schedule. Two variations of this schedule were also examined and compared. Functions relating the highest level of stable fixed‐ratio responding to a wide range of stimulus currents were, unlike those derived from continuous reinforcement rates, monotonic at all stimulation sites tested. One of the procedures described, in particular, is quite sensitive to intracranial reinforcement parameters, provides a reliable technique for within‐session assays of these parameters, and successfully avoids many problems commonly encountered with administration of central stimulation on a continuous reinforcement sch

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-293

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-302

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1968.11-303

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY