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241.
Two versions of a distributed-memory model, one for associative information and one for serial-order information, leave open the question of whether there are two different modes of operation or only one. An analysis of these two versions showed that differential predictions emerge when one considers the role of item information. To test these predictions, a standard item-recognition task (Sternberg, 1966) was embedded in a paired-associate probe-recognition task, a serial-order probe-recognition task, or both. The item-recognition serial-position curves were quite different in the paired-associate and the serial-order conditions, and followed the paired-associate condition when the two were combined. In general, the results were consistent with the predictions of the distributed-memory models, and supported the idea of different modes of operation rather than a single common mode of operation.  相似文献   
242.
243.
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   
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245.
This article presents a series of studies investigating the influence of experimental factors and the personological variables of age and sex upon spatial abilities. It was hypothesized that the overall equivocal findings typical of spatial research may be partially due to the use of different factors across studies. The experimental variables of spatial factor, task demands, spatial information type, information-processing mode, and response mode were systematically manipulated across the eight studies. In each individual analysis of data collected in a specific study, no significant main effect sex differences were detected. However, when a meta-analytic review of the studies was conducted, both spatial information dimensionality and information dimensionality × spatial factor assessed proved to be influential on male and female spatial performances. Female performance was superior when the dimensionality of stimulus and response variables was invariant. Males had the advantage when dimensionality crossing was necessitated. The discrepancy between the sexes was particularly dramatic when the spatial orientation factor was tapped.  相似文献   
246.
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   
247.
248.
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   
249.
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.
In uniquely personal ways, each of these chronically frustrated individuals came to view his or her target either as the personification of the oppressive system, or as the agent through whom he or she could achieve “one great act,” or otherwise gain instant attention and status.  相似文献   
250.
Postpartum and lactational estrus: a comparative analysis in rodentia   总被引:1,自引:0,他引:1  
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   
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