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291.
Király I Jovanovic B Prinz W Aschersleben G Gergely G 《Consciousness and cognition》2003,12(4):752-769
We contrast two positions concerning the initial domain of actions that infants interpret as goal-directed. The 'narrow scope' view holds that goal-attribution in 6- and 9-month-olds is restricted to highly familiar actions (such as grasping). The cue-based approach of the infant's 'teleological stance', however, predicts that if the cues of equifinal variation of action and a salient action effect are present, young infants can attribute goals to a 'wide scope' of entities including unfamiliar human actions and actions of novel objects lacking human features. It is argued that previous failures to show goal-attribution to unfamiliar actions were due to the absence of these cues. We report a modified replication of Woodward (1999) showing that when a salient action-effect is presented, even young infants can attribute a goal to an unfamiliar manual action. This study together with other recent experiments reviewed support the 'wide scope' approach indicating that if the cues of goal-directedness are present even 6-month-olds attribute goals to unfamiliar actions. 相似文献
292.
The word length effect is the finding that short items are remembered better than long items on immediate serial recall tests. The time-based word length effect refers to this finding when the lists comprise items that vary only in pronunciation time. Three experiments compared recall of three different sets of disyllabic words that differed systematically only in spoken duration. One set showed a word length effect, one set showed no effect of word length, and the third showed a reverse word length effect, with long words recalled better than short. A new fourth set of words was created, and it also failed to yield a time-based word length effect. Because all four experiments used the same methodology and varied only the stimulus sets, it is argued that the time-based word length effect is not robust and as such poses problems for models based on the phonological loop. 相似文献
293.
Koch I 《Psychonomic bulletin & review》2003,10(2):488-492
Most studies of task-set switching rely on cuing paradigms, in which external cues indicate the upcoming task. The present study used an entirely predictable task sequence in a variant of the alternating-runs paradigm of Rogers and Monsell (1995). Preparation effects with purely internal memory cues were compared with those in another experimental group with additional external cues presented prior to the stimulus. External cues led to strongly reduced shift costs with prolonged preparation time. However, this effect was much smaller with internal cues only. To account for this differential effect of preparation time as a function of cue type, it is suggested that internal cues select the next task set, which is sufficient to perform the task. External cues additionally facilitate preparatory retrieval of task-specific stimulus-response rules. This account may also explain why incidental task-sequence learning based on internal cues did not reduce shift costs. 相似文献
294.
In a previous study, Kuroshima and colleagues demonstrated that capuchin monkeys (Cebus apella) learned to discriminate between a "knower" who inspected a box for food, and a "guesser" who did not. The aim of the present study was to specify whether the subjects learned a simple conditional discrimination or a causal relationship that seeing leads to knowing. In experiment 1, we introduced five types of novel containers to two subjects. Each container was of different shape and color. The subjects gradually learned to reach toward the container the knower suggested. In experiment 2, we diversified the behavior of the knower and the guesser. In experiment 3, in order to eliminate the possibility of discrimination based on differences in the magnitude and the complexity of two trainers, we equated their behaviors. One subject adapted to the novel behaviors of the knower and the guesser, successfully discriminating the two trainers. Thus this monkey clearly learned to use the inspecting action of the knower and the non-inspecting action of the guesser as a discriminative cue to recognize the baited container. This result suggests that one capuchin monkey learned to recognize the relationship between seeing and knowing. 相似文献
295.
The nature of the association between anger and 5 appraisal-action tendency components--goal obstacle, other accountability, unfairness, control, and antagonism--was examined in terms of specificity, necessity, and sufficiency. In 2 studies, participants described recently experienced unpleasant situations in which 1 of the appraisal-action tendency components was present or absent and indicated which emotions they had experienced. The results showed that (a) other accountability and arrogant entitlement, as an instance of unfairness, are specific appraisals ability for anger; and most important, (b) none of the components is necessary or sufficient for anger. The findings suggest that the relation between emotions and appraisal-action tendency components should be conceptualized instead as a contingent association, meaning that they usually co-occur. 相似文献
296.
Murphy FC Nimmo-Smith I Lawrence AD 《Cognitive, affective & behavioral neuroscience》2003,3(3):207-233
The application of functional neuroimaging to the study of human emotion has yielded valuable data; however, the conclusions
that may be drawn from any one study are limited. We applied novel statistical techniques to the meta-analysis of 106 PET
and fMRI studies of human emotion and tested predictions made by key neuroscientific models. The results demonstrated partial
support for asymmetry accounts. Greater left-sided activity was observed for approach emotions, whereas neural activity associated
with negative/withdrawal emotions was symmetrical. Support was also found for affect program emotion accounts. The activation distributions associated with fear, disgust, and anger differed significantly. These emotions
were most consistently associated in activity in regions associated with selective processing deficits when damaged: the amygdala,
the insula and globus pallidus, and the lateral orbitofrontal cortex, respectively. In contrast, the distributions for happiness
and sadness did not differ. These findings are considered in the context of conceptualizations of the neural correlates of
human emotion. 相似文献
297.
Wong A Escobar M Lesage A Loyer M Vanier C Sakinofsky I 《Suicide & life-threatening behavior》2001,31(1):103-112
Media reports connecting UN peacekeeping duties by Canadian soldiers to their subsequent suicide prompted this study of peacekeeping as suicide risk. In a case-control design we retrospectively compared 66 suicides in the Canadian military between 1990 and 1995 with two control groups: (a) 2,601 controls randomly selected from the electronic military database and (b) 66 matched controls with complete personnel and medical data. We found no increased risk of suicide in peacekeepers except among a subgroup of air force personnel. Here confounding individual factors, isolation from supports, and possibly inadequate preparation for deployment elucidated their suicides. Theater of deployment (e.g., Bosnia) did not affect the suicide rate. Military suicides experienced psychosocial stresses and psychiatric illness more often than their matched controls. We conclude that although peacekeeping per se does not increase overall suicide risk, military life-styles may strain interpersonal relationships, encourage alcohol abuse, and contribute to psychiatric illness and suicide in a minority of vulnerable individuals irrespective of peacekeeping assignment. Careful selection, and preparatory military training that encourages intragroup bonding and mutual support, may protect against suicide risk. 相似文献
298.
The relationships between cognitive and affective attitudes toward the body, body experiences (dissociation, insensitivity, and lack of control), and suicidal tendencies were examined as a derivative of the hypothesis that bodily attitudes and experiences may facilitate suicidal acting out. Three groups of adolescents (aged 14-18), including suicidal (made a suicide attempt) and nonsuicidal inpatients and controls, were compared with regard to suicidal tendencies, various body aspects, and depression and anxiety. A series of MANOVAs, discriminant analysis, Pearson correlations, and regressions were employed. The results show that the suicidal group differed from the two nonsuicidal groups in feelings toward the body, body protection, and body dissociation. Some aspects of bodily measures discriminated between suicidal and nonsuicidal subjects. In addition, various bodily measures were associated with and statistically predicted suicidal tendencies. The discussion focuses on the web of associations between body attitudes and experiences and their role in suicidal behavior. 相似文献
299.
Chronic, severe hypertension does not impair spatial learning and memory in Sprague-Dawley rats 总被引:1,自引:0,他引:1 下载免费PDF全文
This study tested the hypothesis that long-term hypertension impairs spatial learning and memory in rats. In 6-wk-old Sprague-Dawley rats, chronic hypertension was induced by placing one of three sizes of stainless steel clips around the descending aorta (above the renal artery), resulting in a 20–80-mm Hg increase of arterial pressure in all arteries above the clip, that is, the upper trunk and head. Ten months later, the rats were tested for 5 d in a repeated-acquisition water maze task, and on the fifth day, they were tested in a probe trial; that is, there was no escape platform present. At the end of the testing period, the nonsurgical and sham control groups had similar final escape latencies (16±4 sec and 23±9 sec, respectively) that were not significantly different from those of the three hypertensive groups. Rats with mild hypertension (140–160 mm Hg) had a final escape latency of 25±6 sec, whereas severely hypertensive rats (170–199 mm Hg) had a final escape latency of 21±7 sec and extremely hypertensive rats (>200 Hg) had a final escape latency of 19±5 sec. All five groups also displayed a similar preference for the correct quadrant in the probe trial. Together, these data suggest that sustained, severe hypertension for over 10 mo is not sufficient to impair spatial learning and memory deficits in otherwise normal rats. 相似文献
300.
In this editorial contribution, two issues relevant to the question, what should be at the top of the research agenda for ethics and technology, are identified and discussed. Firstly: can, and do, engineers make a difference to the degree to which technology leads to morally desirable outcomes? What role does professional autonomy play here, and what are its limits? And secondly, what should be the scope of engineers' responsibility; that is to say, on which issues are they, as engineers, morally obliged to reflect? The research agendas proposed by the authors contributing to this special section, implicitly, give different answers to these questions. We suggest that an explicit discussion of these issues would greatly help in constructing a common research agenda. 相似文献