ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-165

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Vervet monkeys received food reinforcement contingent on autogrooming. Experiment 1 reinforced grooming on a schedule of increasing intermittency and grooming increased in frequency and duration; with only pauses reinforced, grooming decreased in frequency and duration. Experiment 2 demonstrated differentiation of operant autogrooming; in each session a different single form of grooming was reinforced (for example, grooming the tail only), and that form increased in frequency while other forms became less frequent. In Experiment 3 scratching was succesfully conditioned with a method that selectively reinforced variety in behavior; reinforcement was contingent on a shift in scratching form. In Experiment 4, with no contingencies on grooming, a prefood stimulus did not increase autogrooming whether or not grooming had previously resulted in contingent reinforcement. The form of conditioned autogrooming resembled the form of unconditioned autogrooming. The discussion suggests how reinforcement principles can account for changes in the topography of operant behavior.

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-171

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Stimulus control of schedule‐induced general activity was demonstrated with pigeons using multiple schedules of response‐independent food delivery. In Experiment 1, the introduction of food during a multiple variable‐time 30‐second variable‐time 30‐second schedule produced a tenfold increase in activity above the no‐food baseline. Each pigeon developed stable differential activity rates during the components (correlated with red and green lights) of a multiple variable‐time 30‐second extinction schedule. Lengthening the extinction component from 1 to 7 minutes increased the rate differences and produced a reliable pattern of responding during S— (the stimulus correlated with extinction): Activity rate was high immediately following the change from S+ (the stimulus correlated with variable‐time 30‐second) to S—, then decreased abruptly and remained low throughout the middle of the interval, and subsequently showed a positively accelerated increase until the stimulus changed to S+. In Experiment 2, three pigeons were exposed to a mixed variable‐time extinction schedule prior to a multiple variable‐time extinction schedule. Auditory rather than visual stimuli were used to determine the generality of Experiment 1 results. The multiple‐versus mixed‐schedule results indicated that stimulus control of activity occurred for two of the birds, but rate differences between S+ and S— were much less than those demonstrated with visual stimuli. A direct comparison of visual and auditory stimulus control in Experiment 3 supported this conclusion. These parallels between the stimulus control of reinforced responding and that of schedule‐induced activity suggest that the stimulus control of induced activity may be

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-191

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

An experiment determined whether pigeons minimize number of key pecks per food delivery and maintain their baseline intake of food while key pecking on a three‐component chain schedule. Pigeons at either 80% or 100% body weight obtained all their food during baseline and contingency sessions. During baseline sessions, pecks on the left and center keys had no consequences; each peck on the right key activated the feeder. During contingency sessions, pigeons key pecked on a three‐component chain schedule simulating components of a foraging chain. In thesearch componenteither 3, 9 or 15 key pecks (varied parametrically across blocks of sessions) on the left key produced a stimulus on the middle key, indicating an encounter with either the low‐cost prey (3 key pecks) or an equally probable high‐cost prey (21 key pecks). In theprocurement componentthe pigeon pecked either: (a) the left key once, thus returning to the search component, or (b) the middle key either 3 or 21 times, which activated the right response key. In thehandling componentone peck on the right key operated the feeder. The pigeons always procured the low‐cost prey and minimized the number of key pecks per hopper by procuring the high‐cost prey when the search‐cost ratio was high (15 key pecks) but not when it was low (3 key pecks). All pigeons maintained their baselines of eating during contingency sessions by key pecking more frequently and eating more efficiently. The 80% body‐weight birds produced higher overall rates of key pecking and eating. These results have implications for ecological theories of optimal foraging and for psychological theories of lear

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-211

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Three pigeons were trained on a modified six‐key matching‐to‐sample procedure. The third peck on the figure‐sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two‐component chains or discrete five‐key disc

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-223

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Three experiments were conducted with pigeons to examine the role of the signal in delay‐of‐reinforcement procedures. In the first, a blackout accompanying a period of nonrein‐forcement increased key‐peck response rates maintained by immediate reinforcement. The effects of dissociating the blackout from the delay interval were examined in the second experiment. In three conditions, blackouts and unsignaled delays were negatively correlated or occurred randomly with respect to one another. A signaled delay and an unsignaled delay that omitted the blackouts were studied in two other conditions. All delay‐of‐reinforcement conditions generally produced response rates lower than those produced by immediate reinforcement. Signaled delays maintained higher response rates than did any of the various unsignaled‐delay conditions, with or without dissociated blackouts. The effects of these latter conditions did not differ systematically from one another. The final experiment showed that response rates varied as a function of the frequency with which a blackout accompanied delay intervals. By eliminating a number of methodological difficulties present in previous delay‐of‐reinforcement experiments, these results suggest the importance of the signal in maintaining responding during delay‐of‐reinforcement procedures and, conversely, the importance of the delay interval in

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-239

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Three experiments used concurrent‐chains procedures to examine the effects of reinforcement delay, number of reinforcers, and terminal‐link duration on preference. In Condition 30 of Experiment 1, food was delivered after 30 seconds in each 150‐second terminal link, with four additional food deliveries occurring at 30‐second intervals in one of the links. In Condition 5, food was delivered after 5 seconds in each 25‐second terminal link, and the four additional reinforcers were delivered at 5‐second intervals. Preferences for the multiple‐food chain were greater in Condition 30. In Experiment 2, the terminal link(s) providing only one reinforcer terminated immediately after delivery of the reinforcer. Preferences for the multiple‐food chain were smaller than in Experiment 1. In Condition 5 of Experiment 3, food was delivered after 5, 75, 100, 125, and 150 seconds in one 150‐second link and after 5 seconds in the other. Condition 50 differed only in that the first (or only) reinforcer in each link was delivered after 50 seconds instead of after 5 seconds. Preferences for the multiple‐food chain were greater in Condition 50. Results of Experiments 1 and 2 do not correspond to results obtai

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-255

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Rats' lever pressing produced sucrose reinforcers on a variable‐interval schedule where, in different conditions, the duration of a stimulus presented immediately after reinforcement was either correlated or uncorrected with the duration of the current interreinforcement interval. Under the baseline schedule, in which no stimulus was presented, the minimum interreinforcement interval was 8 s and the mean postreinforcement pause of each subject approximated this value. Response rates increased slowly over the first 10 to 15 s and then remained roughly constant throughout the remainder of the interval. In both the correlated and uncorrected conditions, the added stimulus resulted in the postreinforcement pauses lengthening to values in excess of the duration of the preceding stimulus. This resulted in a poststimulus pause which was, in most cases, roughly constant irrespective of the duration of the preceding stimulus, or of the reinforcement contingencies prevailing immediately after stimulus offset. Local response‐rate patterns in the uncorrelated conditions were similar to those obtained under the baseline schedule in which no stimulus was presented. However, in the correlated condition local response rates increased across the remainder of the interreinforcer interval. Further, the rate of acceleration was inversely related to the duration of the preceding stimulus. These results show that a correlation between stimulus duration and the ensuing time to reinforcement can control behavior—a type of temporal control not previously rep

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-267

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Choice between signaled and unsignaled response‐independent food schedules was assessed in three experiments using a commitment procedure. In Experiment 1, subjects tested with a 5‐s visual signal consistently changed from the signaled to the unsignaled schedule. Changing from the unsignaled to the signaled schedule was observed only occasionally and only at low levels. The same outcome was observed in Experiment 2 with different types of visual signals and with different stimulus combinations identifying the signal period, the signal‐absent period, and the unsignaled schedule. In Experiment 3 the visual signal was replaced with an auditory signal for four of the subjects tested in Experiment 2. The subjects then changed from the unsignaled to the signaled schedule or showed a substantial reduction in choice for the unsignaled schedule. The data were assessed using a conditioned‐reinforcement interpretation of

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-279

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Pigeons responded in a two‐alternative forced‐choice task in which reinforcement was dependent upon the frequency of events that occurred in an immediately preceding schedule sample. On a given trial the events were either brief food presentations or brief visual and auditory stimulus changes. High levels of stimulus control were obtained by food‐presentation schedules only. Discriminative control by frequency or stimulus change was absent. Stimulus control by food frequency was decreased by the imposition of a delay period between the schedule sample and the choice. Moreover, stimulus control by food frequency was related to the ratio of food‐presentation schedule pairs when novel schedules were presented in a transf

ISSN:0022-5002    

DOI:10.1901/jeab.1984.42-291

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY