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231.
These experiments investigate whether or not differences in the way that retarded and nonretarded individuals monitor and regulate speed and accuracy of responding contribute to the slower and more variable performance of retarded subjects on choice reaction time (RT) tasks. Rabbitt (1979, 1981) suggested that efficient choice RT performance is mediated by subjects tracking increasingly faster RT bands on successive trials until, by making and recognizing errors, they discover those very fast RT levels that should be avoided and those safe bands, just above typical error levels, that should be tracked. Experiments 1A and 1B established that most retarded subjects detect their errors as efficiently as nonretarded controls, a finding that excludes the possibility that retarded subjects do not monitor accuracy efficiently but achieve comparable levels of accuracy by consistently responding within very slow RT bands that minimize likelihood of errors. Experiment 2 showed that while a qualitatively similar trial-by-trial tracking mechanism mediates the performance of both groups, retarded subjects are less efficient at constraining RTs within very fast, but safe, bands. Increasing error probabilities at longer RTs suggest that momentary fluctuations in stimulus discriminability and/or attention are factors affecting RT variability in retarded subjects. The RT patterns for various sequences of correct responses initiated and terminated by errors suggest that the effective past experience (EPEX) guiding trial-by-trial RT adjustments of retarded subjects is short and inadequate, and it was argued that this can account for much of the remaining RT variability contributing to retarded-nonretarded differences. Not only does a short EPEX increase variability by giving rise to long error-free sequences of slower than average RT but also, when combined with occasional specified random fluctuations, it suggests why retarded subjects can achieve, but not sustain, RT levels maintained by nonretarded subjects. 相似文献
232.
233.
Stimulus selection in passive avoidance learning and retention: weanling, periadolescent, and young adult rats 总被引:1,自引:0,他引:1
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems. 相似文献
234.
235.
A consecutive series of 30 school refusers received behavioural treatment (BTA). Their outcome is compared with that of 16 school refusers who were hospitalized and 20 who received psychotherapy and home tuition. The BTA group showed superior outcome compared to the other two groups. The Home-tuition group did very badly. There was no evidence of symptom substitution in the 28 cases treated successfully by behaviour therapy. 相似文献
236.
237.
Revision of the self-monitoring scale 总被引:14,自引:0,他引:14
Snyder's (1974) Self-Monitoring Scale exhibits a stable factor structure that does not correspond to the five-component theoretical structure he presents. Sets of face-valid items that better approximate the theoretical structure are described. Correlations between these sets of items and measures of other constructs reveal that four of the five components are positively related to social anxiety. Effective social interaction is supposedly the high self-monitor's forte, and social anxiety appears to be incompatible with this. The correlational results therefore question the entire theory and indicate the need for a narrower definition of the construct. Adopting such a definition from Snyder's review article (1979), we present a 13-item Revised Self-Monitoring scale which measures only sensitivity to the expressive behavior of others and ability to modify self-presentation. A 20-item Concern for Appropriateness scale is also described. This scale measures 2 variables that are directly associated with social anxiety--cross-situational variability and attention to social comparison information. Both scales have acceptable internal consistency, and both yield 2 subscale scores as well as a total score. Prospective users of either scale are advised to treat the 3 scores separately. 相似文献
238.
Marshall N. Heyman 《Behavioral sciences & the law》1984,2(2):131-149
Twenty-two people who were presidential assassins and other similarly dangerous persons were assessed from information contained in Secret Service files and in published accounts. These documents were studied in order to determine common characteristics as well as other clues to the identification of potentially dangerous persons. Although there was no single pattern of development, there was a pattern of maladjustment that embraced common feelings of inadequacy or persecution, which led to similar patterns of behavior when attempting to resolve frustration. In practical terms, these profiles show:
- 1 A systematic pattern of inadequacy in dealing with social, intellectual, and vocational challenges.
- 2 A corresponding absence of any positive channel for achieving satisfaction or a sense of accomplishment.
239.
A N Gilbert 《Journal of comparative psychology (Washington, D.C. : 1983)》1984,98(3):232-245
Virgin rodents exhibiting cycling estrus have traditionally been used for comparative studies of reproductive behavior. However estrus occurs in other life-history contexts, some of which differ from cycling estrus (CE) in that (a) the female is disposed to behave both maternally and sexually and (b) they result in litter overlap (i.e., the simultaneous gestation and lactation of two litters). In this report, two of these other modes of estrus are examined, with emphasis on their evolutionary and ecological implications. By means of a literature search of the order Rodentia, postpartum estrus (PPE) and lactational estrus (LE) were documented in 15 families, 71 genera, and 141 species. Analysis of these data showed that PPE and LE were nonrandomly distributed across taxa. They were statistically overrepresented in the family Cricetidae and underrepresented in squirrels (Sciuridae) and in pocket mice and kangaroo rats (Heteromyidae). Analysis of the phenotypes by which PPE and LE are achieved suggests important differences between them and CE in several parameters of female reproductive effort and breeding strategy, including maternal and copulatory behavior, optimal timing of litters, and hormonal control of heat and lactation. 相似文献
240.