摘要:

Two studies investigated the transfer of respondent elicitation through equivalence classes. In Experiment 1, match‐to‐sample procedures were used to teach 8 subjects two four‐member equivalence classes. One member of one class was then paired with electric shock, and one member of the other class was presented without shock. All remaining stimuli were then presented. Using skin conductance as the measure of conditioning, transfer of conditioning was demonstrated in 6 of the 8 subjects. In Experiment 2, similar procedures were used to replicate the results of Experiment 1 and investigate the transfer of extinction. Following equivalence training and conditioning to all members of one class, one member was then presented in extinction. When the remaining stimuli from this class were then presented, they failed to elicit skin conductance. In the final phase of the experiment, the stimulus that was previously presented in extinction was reconditioned. Test trials with other members of the class revealed that they regained elicitation function. These results demonstrate that both respondent elicitation and extinction can transfer through stimulus classes. The clinical and applied significance of the results is disc

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-331

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Pigeons' choices between a reliable alternative that always provided food after a delay (i.e., 100% reinforcement) and an unreliable one that provided food or blackout equally often after a delay (i.e., 50% reinforcement) was studied using a discrete‐trials concurrent‐chains procedure modified to prevent choice between alternatives following a blackout outcome. Initial links were fixed‐ratio 1 schedules, and terminal links were fixed‐time schedules. Stimuli presented during the terminal‐link delays were correlated with the food and blackout outcomes. In Experiment 1, terminal‐link durations were varied. With short terminal links (i.e., 10 s), 6 of 8 subjects showed strong preference for the 50% side. As terminal‐link duration increased to 30 s, preference, regardless of direction, became less extreme. In Experiment 2, the side‐key location of the 50% and 100% alternatives was reversed for 3 subjects. Preference for the 50% alternative reoccurred following the key reversal. When a 5‐s separation was subsequently interposed between the initial and terminal links for both alternatives, all birds reversed to a preference for the 100% side. In general, the strong preference for the 50% side was qualitatively consistent with the expectation that the procedure enhanced the conditioned‐reinforcement effectiveness of the food‐associated terminal‐link stimulus on the 50% side. Implications of the results for various accounts of choice of the 50% al

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-353

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Four adult humans chose repeatedly between a fixed‐time schedule (of points later exchangeable for money) and a progressive‐time schedule that began at 0 s and increased by a fixed number of seconds with each point delivered by that schedule. Each point delivered by the fixed‐time schedule reset the requirements of the progressive‐time schedule to its minimum value. Subjects were provided with instructions that specified a particular sequence of choices. Under the initial conditions, the instructions accurately specified the optimal choice sequence. Thus, control by instructions and optimal control by the programmed contingencies both supported the same performance. To distinguish the effects of instructions from schedule sensitivity, the correspondence between the instructed and optimal choice patterns was gradually altered across conditions by varying the step size of the progressive‐time schedule while maintaining the same instructions. Step size was manipulated, typically in 1‐s units, first in an ascending and then in a descending sequence of conditions. Instructions quickly established control in all 4 subjects but, by narrowing the range of choice patterns, they reduced subsequent sensitivity to schedule changes. Instructional control was maintained across the ascending sequence of progressive‐time values for each subject, but eventually diminished, giving way to more schedule‐appropriate patterns. The transition from instruction‐appropriate to schedule‐appropriate behavior was characterized by an increase in the variability of choice patterns and local increases in point density. On the descending sequence of progressive‐time values, behavior appeared to be schedule sensitive, sometimes even optimally sensitive, but it did not always change systematically with the contingencies, suggesting the involve

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-367

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Pigeons were trained on a concurrent‐chains schedule. The initial links were concurrent variable‐interval schedules arranged on two side keys. Each terminal link was a fixed‐interval schedule arranged on the center key. In cued conditions, different center‐key colors signaled the two terminal‐link schedules. In uncued conditions, the same center‐key color appeared for both terminal links. Experiment 1 arranged unequal initial links and equal terminal links. Preference for the shorter initial‐link schedule was greater when the terminal links were uncued. Experiment 2 arranged equal initial links and unequal terminal links. Preference for the shorter terminal‐link schedule was greater when the terminal links were cued. Although the results of Experiment 2 successfully replicated previous research, the results of Experiment 1 are not easily reconciled with conditioned‐reinforcement or discriminative‐stimulus accounts of the role of terminal‐link cues. Rather, terminal‐link cues appear to decrease sensitivity to ini

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-385

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Four homing pigeons were trained over 5 months in a zero‐delay, “arbitrary” matching‐to‐sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed‐ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhum

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-399

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Several theories in the learning literature describe decision rules for performance utilizing ratios and differences. The present paper analyzes rules for choice based on either delays to food, immediacies (the inverse of delays), or rates of food, combined factorially with a ratio or difference comparator. An experiment using the time‐left procedure (Gibbon&Church, 1981) is reported with motivational differentials induced by unequal reinforcement durations. The preference results were compatible with a ratio‐comparator decision rule, but not with decision rules based on differences. Differential reinforcement amounts were functionally equivalent to changes in delays to food. Under biased reinforcement, overall food rate was increased, but variance in preference was increased or decreased depending on which alternative was favored. This is a Weber law finding that is compatible with multiplicative, scalar sources of variance but incompatible with pacemaker rate changes proportional to food presentation r

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-409

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1994.62-435

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY