ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-197

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Three pigeons searched arrays of alphabetic letters displayed on computer monitors. On each trial, either an A or an E appeared, and the reaction time and accuracy with which the bird pecked at this target were measured. In each block of trials, each target (A or E) was displayed alone, or together with a number of distractor letters (2 or 18) that varied in their similarity to the target. During a baseline series of sessions, responses to the A and to the E each yielded food reinforcement on 10% of the trials. In the next series of sessions, reinforcement continued at 10% for A, but rose to 30% for E. In a final series, these reinforcement conditions were reversed. As expected, reaction times increased with target‐distractor similarity and (for similar distractors) with the number of distractors. Increased reinforcement of E had no effect on reaction times to E, but produced a very consistent increase in reaction times to A; the average increase was constant across the various display conditions. Reversal of the differential reinforcement conditions reversed this contrast effect. Analysis of the reaction time distributions indicated that increased reinforcement to E decreased the momentary probability of response to A by a constant amount, regardless of display conditions. These results are discussed in relation to theories of contrast, memory, and of the search imag

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-199

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

In Experiment 1, one group of pigeons learned to classify a set of stimuli into the human languageclasses cat, flower, car, and chair(categorization); another group learned to classify the same set into arbitrary classes (pseudocategorization). Then, both groups were trained on a new categorization task and their performance compared to that of a control group that had no initial classification training. Hull's (1943) notion of secondary generalization (generalization that is not based on physical similarity but on mediating associations) predicts that categorization experience will facilitate the learning of a new categorization task, whereas pseudocategorization experience will impair it. However, in Experiment 1, performance on the new categorization task was not differently affected by prior experience. In Experiment 2, pigeons initially trained to classify a set of 48 stimuli (original training) were later trained to classify a subset of four of these stimuli using new responses (reassignment training). Then, they were tested on the 44 remaining stimuli. Performance better accorded with original than with reassignment training, indicating that categorization training did not lead to the formation of equivalence classes of stimuli, in which the equivalence relationship is mediated by secondary generalization. The lack of evidence of secondary generalization implies that our pigeons failed to meet Lea's (1984) criterion for conceptual behavior.

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-213

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Two cebus monkeys, with many years of experience matching a variety of static visual stimuli (forms and colors) within a standard matching‐to‐sample paradigm, were trained to press a left lever when a pair of displayed static stimuli were the same and to press a right lever when they were different. After learning the same/different task, the monkeys were tested for transfer to dynamic visual stimuli (flashing versus steady green disks), with which they had no previous experience. Both failed to transfer to the dynamic stimuli. A third monkey, also with massive past experience matching static visual stimuli, was tested for transfer to the dynamic stimuli within our standard matching paradigm, and it, too, failed. All 3 subjects were unable to reach a moderate acquisition criterion despite as many as 52 sessions of training with the dynamic stimuli. These results provide further evidence that, in monkeys, the matching (or identity) concept has a very limited reach; they consequently do not support the view held by some theorists that an abstract matching concept based on physical similarity is a general endowment of anim

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-225

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Three experiments showed stimulus control by either the absolute properties of probe stimuli, relational properties of the probe‐list relationship, or both in a serial probe recognition memory task in which a four‐item memory list was followed by a single probe (test) item. In Experiment 1, 3 rhesus monkeys received 39 to 75 repetitions of the same 24‐trial stimulus sequence. Special tests showed stimulus control by the absolute properties of the probe stimuli. Retention of previous relational control was demonstrated by the good transfer (83%) to novel list and probe stimuli at the beginning of Experiment 2. During Experiment 2, control by absolute properties of the probe stimuli gradually reoccurred. Only a small measure of control by list stimuli could be detected or promoted. In Experiment 3, 4 monkeys were shown to have largely lost their ability to perform on the basis of the list‐probe relationship, and were performing primarily on the basis of the absolute properties of the probe stimuli. Over the next 15 weeks, these monkeys were transferred to new stimuli at the beginning of each week. Control by the relational aspects of the task gradually returned. As transfer performance increased, control by the absolute properties of the probe stimuli was eliminated. The results are discussed in terms of stimulus control and performance strategies used by the

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-237

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Four experiments demonstrate that when putative conditional and discriminative cues are presented simultaneously in the single reversal procedure, it is not possible to ascribe a uniquely conditional or uniquely discriminative function to either of the cues. In Experiment 1, pigeons were trained to respond to a blue key and not to a red key while the houselight was on; then in a different session they learned the reversal of this discrimination with the houselight off (single reversal). Separate groups were tested for color generalization with houselight conditions alternating in blocks of trials or for houselight intensity generalization with blue and red key colors alternating in blocks of trials. Both test procedures revealed a conditional relationship between houselight and key color conditions. Experiment 2 produced the same result following training in which the key colors were held constant across training sessions while the houselight and no houselight conditions varied within sessions. In Experiment 3, separate groups were trained with the two procedures but were tested with randomly ordered combinations of key colors and houselight intensities. The two groups yielded indistinguishable bidimensional generalization gradients with peaks at both previously reinforced stimulus combinations. In Experiment 4 the subjects were switched from one of these training procedures to the other with no decrement in their discriminative performance. We conclude that for successive discriminations between conditional‐ and discriminative‐stimulus combinations, the notion of a hierarchical relation between conditional and discriminative stimuli must be extended to include a symmetrical relationship or the notion should be abandoned altoget

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-249

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Three adult subjects were taught a set of two‐choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within‐class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two‐choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within‐class conditional relations after the equivalenc

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-261

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The present study examined the occurrence of a novel behavior pattern with respect to a novel configuration of stimuli enabled by the participation of those stimuli in equivalence classes. In Experiment 1, functional substitutabilities were established via equivalence between two independent sets of musical stimuli. Aspects of stimuli from the two sets were then compounded to produce novel stimulus configurations. Behavioral components enabled by each separate class combined to produce novel musical performances and accurate descriptions of them. In Experiment 2, the impact of experimenter‐provided names for equivalence classes on the musical performances was investigated in naive subjects by establishing similar classes without experimenter‐provided names. The results indicated few differences in the playing performances under these conditions. These experiments demonstrated a possible method for the analysis of rule follow

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-275

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Three experiments examined the performance of 4‐year‐old children in matching geometric stimuli. Performance was developed as a simulation in which all components of the behavior were overt and directly measured. A correct match depended on the state of an instructional stimulus: the background color of the display. In the first two experiments, on nonidentity trials (signified by a green background) the next longer length, larger size, or greater distance was correct. With a blue background, a comparison identical to the sample was correct. In Experiment 3, red was added for which shorter, smaller, or nearer was correct. Also here, on nonidentity trials, if a comparison of the correct length was not presented, the children adjusted their search target to the comparison of the next succeeding size (larger or smaller) so as to maintain a constant matching relation. Subsequently, when exposure to the instructional stimulus was reduced to presentation only at the beginning of each trial, performance simulated matching based on instructions about abstract relations. In all experiments, accurate matching generalized across novel stimuli and reduced exposure to the instructional stim

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-293

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Pigeons' short‐term memory for fixed‐ratio requirements was assessed using a delayed symbolic matching‐to‐sample procedure. Different choices were reinforced after fixed‐ratio 10 and fixed‐ratio 40 requirements, and delays of 0, 5, or 20 s were sometimes placed between sample ratios and choice. All birds made disproportionate numbers of responses to the small‐ratio choice alternative when delays were interposed between ratios and choice, and this bias increased as a function of delay. Preference for the small fixed‐ratio alternative was also observed on “no‐sample” trials, during which the choice alternatives were presented without a prior sample ratio. This “choose‐small” bias is analogous to results obtained by Spetch and Wilkie (1983) with event duration as the discriminative stimulus. The choose‐small bias was attenuated when the houselight was turned on during delays, but overall accuracy was not influenced systematically b

ISSN:0022-5002    

DOI:10.1901/jeab.1989.52-311

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY