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991.
An outcome-expectancy mediation theory of learning was tested in a series of transfer experiments with pigeons. The principal technique employed was a delayed two-choice conditional discrimination in which the subject's correct choice yielded a food reward on one kind of trial and a feedback tone on the other. According to the theory, this task engenders two-link mediational chains in that each conditional cue controls a particular outcome expectancy (S-E link) and the expectancy, in turn, cues a specific choice response (E-R link). Relative to the hypothetical mediators established by preceding training, transfer problems required either the same mediational chains, the alteration of one link in each chain, or the alteration of both links in both chains for optimal performance. The results of four separate transfer experiments confirmed detailed theoretical predictions, including that of an unusual nonmonotonic transfer effect. The relation of the present theory to earlier mediation theories is discussed.  相似文献   
992.
Two experiments were conducted to determine if rats tend to avoid contact with a stimulus that signals the occurrence of shock and contact a stimulus that signals the nonoccurrence of shock. The conditioned stimulus was a 60-sec platform presentation, and the unconditioned stimulus was a 2-sec inescapable shock. In each experiment, the emphasis was on two types of Pavlovian pairings: forward pairing in which each platform presentation was followed by shock, and backward pairing in which each platform presentation was preceded by shock and followed by a lengthy shock-free interval. Experiment 1 showed that in comparison with Random and CS-only procedures, the backward procedure produced a significant increase in approach and contact with the platform, but the forward procedure failed to produce a significant decrease in contact with the platform. Experiment 2, in which all groups were roughly equated for baseline levels of platform preference, demonstrated strong effects of both forward and backward conditioning. The experiments provide evidence for an aversive sign-tracking system in which animals' tendencies to withdraw from or approach and contact a platform CS are determined by the Pavlovian contingencies which render it a reliable signal for the occurrence or nonoccurrence of shock.  相似文献   
993.
Seven major preschool tests were administered to a group of 322 kindergarten children. Scaled scores from the instruments were submitted to principal factoring, with iterations for the total sample and separately by race/sex groupings. The average intercorrelation of the pretests was similar across race and sex. A two-factor solution of the battery was derived for the total group and for each of the four subgroups (WF, WM, BF, BM). The two-factor solution was highly similar across race and sex, as indicated by the large coefficients of congruence obtained between factors derived within each group, thus supporting the equivalence of internal psychometric properties of the battery across race and sex. No evidence was determined to support sexual or racial dimorphism in the early structure of cognitive abilities.  相似文献   
994.
In Experiment 1, pigeons exposed to US ONLY pretraining were observed to be retarded in the acquisition of autoshaping relative to naive controls; however, gross changes in contextual stimuli between pretraining and testing alleviated the retardation effect. In Experiment 2, groups of pigeons exposed to CS ONLY, US ONLY, or random CS-US presentations (TRC) were tested for the acquisition of autoshaping. The US ONLY and TRC groups were retarded relative to naive controls. The context change manipulation eliminated the US ONLY retardation effect and attenuated, but did not eliminate, the TRC retardation effect. Context blocking accounts for the US ONLY effect and contributes to the TRC effect; however, context-independent retardation following TRC pretraining suggests the operation of the learned irrelevance cognition.  相似文献   
995.
Three experiments used a flavor-aversion preparation to demonstrate the occurrence of within-compound associations in various conditioning procedures. In Experiment 1 rats first received two separate two-flavor compounds, each followed by a mild US. They then received one element from one compound paired with a strong US and one element from the other compound nonreinforced. A subsequent choice test of the other two flavors from the compounds revealed that the consumption of each test flavor reflected the conditioning history of the element with which it had been paired. Rats drank less of the flavor whose associate had been paired with the strong US than of the flavor whose associate had been nonreinforced. In Experiment 2 within-compound associations were observed using a similar design in a blocking procedure in which one element from each of the two compounds was conditioned previously. Experiment 3 identified within-compound associations in a procedure where reinforced single element presentations were intermixed with nonreinforced compound presentations, as in a conditioned inhibition paradigm. These results suggest that within-compound associations occur in several important conditioning procedures which use multiple CS presentations.  相似文献   
996.
M. J. Lavin, B. Freise, and S. Coombes (Behavioral and Neural Biology, 1980, 28, 15–33) have shown that if two rats consume a flavored solution and one is poisoned, the unpoisoned partner will also exhibit a flavor aversion during a later preference test. Experiments 1 and 2 showed that a sufficient condition for obtaining this aversion is that the poisoned partner be present with the unpoisoned rat after it has consumed the flavored solution. It is not necessary that the poisoned partner be present when the flavored solution is consumed or indeed have had any exposure to the flavored solution. Experiment 3 showed that the unpoisoned partner can exhibit a flavor aversion when there is a temporal gap of as long as 6 hr between consumption of the flavored solution and exposure to the poisoned rat.  相似文献   
997.
Internals and externals observed a staged videotape presentation that portrayed a “teacher” and a “learner” engaging in a 20-item anagrams task. For externals, any variability (10, 50, and 90% schedule) in the reinforcing behavior of the “teacher” (agent of reinforcement) resulted in significantly greater perceived freedom than when no variability (0 and 100% schedule) occurred in behavior. For internals, perceived freedom was a negative linear function of the amount of reinforcement administered. Internals indicated that they could influence the behavior of the “teacher” in all reinforcement conditions, whereas externals indicated that they could influence only the “teachers” in the variable reinforcement conditions. It was concluded that greater freedom is attributed to a person whose behavior is perceived as congruent with the person's inner disposition.  相似文献   
998.
Subjects made three ratings for each of 30 words, then had an unannounced immediate free recall test and a second test after 1 week. There was no evidence to indicate significantly better retention on either test when the dimensions rated were unrelated as opposed to related. Subjects low on test anxiety performed better overall than subjects who scored high on either the emotionality or worry components of test anxiety. On the delayed test, the test anxiety effect was apparent only when study ratings involved unrelated dimensions (i.e., broad encoding). This interaction is consistent with two conclusions. First, rating related dimensions led to narrow encodings, thus hindering low-anxiety subjects who normally encode broadly. Second, even explicit ratings of unrelated dimensions did not induce high-anxiety subjects to encode more broadly. That the high-anxiety deficit was not overcome even with explicit orienting tasks may indicate inflexibility in deploying memory strategies.  相似文献   
999.
Some theoretical and applied implications of individual differences in nonverbal expressiveness were investigated in a medical setting. In Study I, the abilities of 21 physicians to express different emotions through voice tone were assessed and related to physician personality and to actual patient ratings of the physician. Study II replicated Study I using visual as well as vocal cues (i.e., videotapes) of a new sample of physicians, and added a study of physician greetings. It was found that: (1) Aspects of expressive ability were reliably correlated with a cluster of personality traits, thus supporting the notion that nonverbal affective style may be a window to inner dispositions; and (2) expressive ability was related to patient satisfaction with the interpersonal manner of their physicians and to the judged likeability of the physician's greeting, thus providing evidence for the importance of this ability for social interaction.  相似文献   
1000.
Recently it has been claimed that alcoholic amnesic patients mainly engage in passive repetitive rehearsal during spontaneous learning and that this contributes to their memory problem. To test this hypothesis further, two experiments were conducted which compared list learning in amnesic patients and normal controls. In Experiment I both groups of subjects were required either to learn a list which was presented five times consecutively with free recall following each presentation, or they were asked to repeat each word out loud as they saw it and carry on doing so until the next word was shown. Five presentation trials were given and free recall was again tested after each presentation. It was predicted that if the amnesics' spontaneous form of learning involved only passive repetition there should be no difference between learning and repetition for this group while the controls should show an impairment in repeating compared to learning. The results showed that both groups of subjects were impaired to the same extent with repeating compared to learning and it was concluded that spontaneous learning was similar in both groups and that neither group merely passively rehearsed during spontaneous learning. A second experiment examined recognition performance of the two groups of subjects after learning or repeating lists of 20 words. Recognition was tested with distractors which were irrelevant, acoustically similar, graphemically similar, or semantically similar to the target word. It was found there were no differences between either of the groups in the pattern of errors made over the different distractor types. It was thus concluded that there was no encoding or rehearsal abnormality in the amnesic group. The possibility of differences between groups of alcoholic amnesics was discussed as well as the putative role of slow cognitive processing in their memory problems.  相似文献   
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