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991.
Event representation in Pavlovian conditioning: image and action   总被引:1,自引:0,他引:1  
P C Holland 《Cognition》1990,37(1-2):105-131
In a typical Pavlovian conditioning experiment, a relatively insignificant event, the conditioned stimulus (CS), is paired with a biologically more meaningful event, the unconditioned stimulus (US). As a consequence of those pairings, the CS is thought to acquire response characteristics of the US. In this article I describe experiments with rats that suggest that under some circumstances, the CS acquires control of perceptual processing of the US, in the absence of that US itself. I present three kinds of evidence for this surrogate processing, which I liken to imagery or hallucination: (1) CSs come to control specific, sensory-evaluative responses normally evoked only by the USs; (2) CSs can substitute for USs in the establishment of new learning about those USs themselves; (3) CSs can substitute for USs in the modulation of conditioning to other events, either overshadowing (interfering) or potentiating learning, in the same manner as the USs themselves. Finally, I compare these data with evidence for conditioned sensation and imagery in humans, and suggest that imagery may be a very basic process, evolutionarily derived from perceptual and conditioning processes adapted to deal with remote or absent objects.  相似文献   
992.
This study analysed the way 20 managers in the information technology industry in Australia viewed their lives, and identified two dimensions of central importance cutting across the work, family and leisure spheres encompassed by them. One dimension was positively loaded towards activities which were challenging, creative and under the individual's control. These activities were enjoyable, and included examples such as consulting with clients, creating new business, and communicating and dealing with others, whether at work or at home. The opposite pole of this dimension involved activities such as completing paperwork, general administration, doing the shopping, and disciplining the children. Such activities were seen as necessary, routine or stressful, and were generally disliked. The other dimension dealt with activities which, at one pole, were emotionally involving or involved moral standards, and included examples such as attending meetings, doing things as a family, and settling disputes, either at work or at home. At the other pole were activities which were usually done alone and involved no sense of social or moral obligation. Leisure activities typically fell into this category. The results indicated that these managers generally pursued a lifestyle which was seen to be non-stressful, and one valued for the challenge, enjoyment, freedom of choice and personal control which it offered.  相似文献   
993.
Congruence of personality and life events in depression   总被引:2,自引:0,他引:2  
Consistent with the personality-event congruence hypothesis, highly sociotropic depressed patients (n = 19) reported more recent negative interpersonal events than negative autonomy events and more negative interpersonal events than did highly autonomous depressed patients (n = 22), for whom the hypothesis was not supported. There was no evidence of such congruence among nondepressed schizophrenic patients (n = 44). In a second study, there was significant personality-event congruence in dysphoric students (n = 26) but not in nondysphoric students (n = 56). Both the high-sociotropy and high-autonomy dysphoric groups separately yielded nonsignificant trends consistent with congruence. These findings add to the growing support for the importance of the sociotropy construct in depression and weaker support for the autonomy construct or its measurement, and they suggest that the congruence effect does not generalize to all psychopathologies.  相似文献   
994.
Two studies provided evidence that alcohol's relationship to psychological stress is indirect and is mediated by the allocation of attention. Study 1 found that, as the attentional demands of a distracting activity increased, so did alcohol's reduction of anxiety. Study 2 replicated this effect and found that a highly demanding activity could reduce anxiety even without alcohol. This study further implicated the role of attention in anxiety reduction by demonstrating a relationship between changes in anxiety and response latency to a secondary monitoring task. Finally, in both experiments, intoxicated subjects who did not perform any activity showed an increase in anxiety. From these data, we argue that alcohol affects psychological stress, to an important degree, through its ability, in conjunction with ongoing activity, to affect the amount of attention paid to stressful thoughts.  相似文献   
995.
Peer-group association and adolescent tobacco use   总被引:10,自引:0,他引:10  
Mosbach & Leventhal (1988) examined the relation of cigarette smoking to peer-group identification in rural Wisconsin adolescents. They found that among dirts (problem-prone youth), regulars (average youth), hot-shots (good social or academic performers), and jocks (athletes), youth most likely to smoke were dirts and hot-shots. We performed a replication with a Southern California cohort and also for use of smokeless tobacco. We hypothesized that jocks would be the main users of smokeless tobacco. We identified the same groups and an additional one, skaters (skateboarders or surfers). As Mosbach & Leventhal found, cigarettes were used most by dirts. Contrary to their results, but consistent with other research, we found that hot-shots were least likely to smoke. Contrary to our prediction, we found that skaters and dirts were more likely to use smokeless tobacco than were jocks. Our data show that both tobacco forms are used by problem-prone youth.  相似文献   
996.
Endorsement of dysfunctional beliefs depends on current mood state   总被引:2,自引:0,他引:2  
In two studies we tested the hypothesis that endorsement of dysfunctional beliefs depends on current mood state for persons who are vulnerable to depression. The first study showed that reports of dysfunctional beliefs vary with spontaneous diurnal mood fluctuations in 47 depressed psychiatric patients. The effect of mood state was highly significant (p less than .01); dysfunctional thinking increased when mood was worst and decreased when mood was best. The second study conceptually replicated this finding in a population of asymptomatic subjects. As predicted, reports of dysfunctional beliefs varied as a function of mood state in 14 persons who had experienced a depressive episode but not in 27 who had never been depressed. These findings support the cognitive theory of depression, which proposes that dysfunctional beliefs are vulnerability factors for depression but also that reporting of dysfunctional beliefs depends on current mood state.  相似文献   
997.
Selective processing of threat cues in posttraumatic stress disorder   总被引:1,自引:0,他引:1  
Vietnam combat veterans with (n = 15) and without (n = 15) posttraumatic stress disorder (PTSD) performed a modified Stroop task in which they named the colors of neutral words (e.g., INPUT), positive words (e.g., LOVE), obsessive-compulsive disorder (OCD) words (e.g., GERMS), and PTSD words (e.g., BODYBAGS). In contrast to normal controls, PTSD patients took significantly longer to color-name PTSD words than to color-name neutral, OCD, and positive words. Because Stroop interference reflects involuntary semantic activation, it may provide a quantitative measure of intrusive cognitive activity--the hallmark symptom of PTSD.  相似文献   
998.
This study is to report a cross-cultural comparison on perceptions of icons and graphics and their relationships. Data were ratings of 10 icons and 10 graphics against 21 bipolar semantic differential scales from 325 college students in three countries, Mexico, Columbia, and Japan. Cross-cultural factor analyses resulted in the identification of four semantic (three affective and one denotative) features, three icon factors, and three graphic factors. Indigenous cultural means of these iconic and graphic factors were computed and used to probe cross-cultural similarities and differences in perceptions. Psychosemantics of icon factors were further predicted by graphic factors through canonical correlation. This study concludes the importance of implicit cultural meanings of nonverbal figures in intercultural communications. The implications of this study are also discussed.  相似文献   
999.
To see if suicide ideators responded differently than nonideators after success or failure experiences, 61 college students who were relatively high or low ideators participated in a computer task on which half got bogus success feedback, the other half got bogus failure feedback. Both groups then completed the Reasons for Living Inventory (RFL). Two (High versus Low Suicide) X 2 (Success or Failure) analyses indicated main effects for suicide on overall RFL and four of the six RFL subscales. Although there were no main effects for success versus failure, an interaction indicated that, in the failure condition, low suicidal subjects were significantly higher than high suicidal subjects in overall reasons for living. Results suggest that suicidal individuals may be vulnerable to failure, and may need interventions to help them avoid potential failure or to bolster their coping mechanisms.  相似文献   
1000.
The purpose of this research was to investigate rule learning in reading disabled (RD) and normal children (chronological age and reading age (RA) match) when required to (a) abstract rules independently, and (b) use rules after instruction. Study 1 required the children to solve problems using shapes and letters. Although there was no difference between groups in the rate of problem solving when children were asked to abstract rules independently, the pattern of errors was different. The RD children made a greater proportion of errors on the negative instance for the more complex problems. In particular, this occurred on the letter task which involved psycholinguistic categorization. After instruction, the RA controls made more errors than the other groups. Study 2 was an analogous pseudoword reading task. Even with statistical adjustment for differences in prior grapheme-phoneme (g-p) rule knowledge, the RD children performed less accurately than the RA controls when they had to abstract rules, although this was restricted to the most difficult rule (rule of e). There was no difference after instruction in rule application, although the pattern of errors and post-test results indicated that the RD children continued to experience decoding difficulty. These results suggest a phonologically based productive deficit which interferes with the learning of g-p rules. This may be part of a more general language deficit which includes psycholinguistic categorization. Despite the severity of this handicap, RD children seem responsive to instruction.  相似文献   
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