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181.
To assess the psychological and family factors associated with suicidal ideation in pre-adolescent children, we studied a sample of 361 students, average age 9 years old. Two groups were formed, on the basis of the presence (n = 34) or absence (n = 44) of suicidal ideation. Suicidal ideation was assessed with the Children's Depression Inventory and the Children's Depression Rating Scale-Revised. Depression, hopelessness, self-esteem, and perceived family environment were compared in both the suicidal ideation and the control groups. Students with suicidal ideation generally presented greater depressive symptoms and hopelessness, and lower self-esteem and family expressiveness, although there were differences both between sexes, and when the variable depression was controlled. Identifying these risk factors in pre-adolescents may have an impact on prevention of suicidal behavior at higher risk ages.  相似文献   
182.
For scientific knowledge to be trustworthy, it needs to be dissociated from material interests. Disinterested research also performs other important non-instrumental roles. In particular, academic science has traditionally provided society with reliable, imaginative public knowledge and independent, self-critical expertise. But this type of science is not compatible with the practice of instrumental research, which is typically proprietary, prosaic, pragmatic and partisan. With ever-increasing dependence on commercial or state funding, all modes of knowledge production are merging into a new, ‘post-academic’ research culture which is dominated by utilitarian goals. Growing concern about conflicts of interest is thus a symptom of deep-seated malaise in science and medicine. An expanded version of this paper was presented at an International Conference on “Conflict of Interest and its Significance in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002.  相似文献   
183.
Moral psychology has long focused on reasoning, but recent evidence suggests that moral judgment is more a matter of emotion and affective intuition than deliberate reasoning. Here we discuss recent findings in psychology and cognitive neuroscience, including several studies that specifically investigate moral judgment. These findings indicate the importance of affect, although they allow that reasoning can play a restricted but significant role in moral judgment. They also point towards a preliminary account of the functional neuroanatomy of moral judgment, according to which many brain areas make important contributions to moral judgment although none is devoted specifically to it.  相似文献   
184.
Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication  相似文献   
185.
In 2001, the U.S. House of Representatives passed the "Human Cloning Prohibition Act" and President Bush announced his decision to allow only limited research on existing stem cell lines but not on "embryos." In contrast, the U.K. has explicitly authorized "therapeutic cloning." Much more will be said about bioethical, legal, and social implications, but subtleties of the science and careful definitions of terms have received much less consideration. Legislators and reporters struggle to discuss "cloning," "pluripotency," "stem cells," and "embryos," and whether "adult" are preferable to "embryonic" stem cells as research subjects. They profess to abhor "copying humans" or "killing embryos." Do they know what they are talking about? Do we? This paper explores the historical, philosophical, and scientific contexts that inform this heated discussion.  相似文献   
186.
Prior studies provide consistent evidence of deficits for psychopaths in processing verbal emotional material but are inconsistent regarding nonverbal emotional material. To examine whether psychopaths exhibit general versus specific deficits in nonverbal emotional processing, 34 psychopaths and 33 nonpsychopaths identified with Hare's (R. D. Hare, 1991) Psychopathy Checklist--Revised were asked to complete a facial affect recognition test. Slides of prototypic facial expressions were presented. Three hypotheses regarding hemispheric lateralization anomalies in psychopaths were also tested (right-hemisphere dysfunction, reduced lateralization, and reversed lateralization). Psychopaths were less accurate than nonpsychopaths at classifying facial affect under conditions promoting reliance on right-hemisphere resources and displayed a specific deficit in classifying disgust. These findings demonstrate that psychopaths exhibit specific deficits in nonverbal emotional processing.  相似文献   
187.
Preactivation of particular content categories in memory yields latency differences in a visual recognition task. Two Internet studies demonstrate this content category superiority effect (CCSE). Target words are repeatedly flashed for 400 ms and then masked for 200 ms. Experiment 1 shows that differences in pre-activated memory content, related to participants' use of computer operating systems, influence z-scored visual word recognition latencies. Experiment 2 shows that this influence is susceptible to instruction. Participants expecting to find positive words recognized those words faster, whereas participants expecting to find negative words were faster on negative words. The CCSE provides a basis on which new measures of implicit memory content can be founded. Two such applications are discussed--the Motive Superiority Measure of implicit motives, and a latency-based measure of self-focused attention.  相似文献   
188.
Hearing and deaf children, ranging in age from 6 years 8 months to 14 years 4 months, and matched for general spelling level, were required to spell high-frequency and low-frequency words. Of interest was performance in relation to degree of exposure to Cued Speech (CS), which is a system delivering phonetically augmented speechreading through the visual modality. Groups were (a) hearing children, (b) deaf children exposed early and intensively to CS at home (CS-Home), and (c) deaf children exposed to CS later and at school only (CS-School). Most of the spelling productions of hearing children as well as of CS-Home children were phonologically accurate for high-frequency as well as for low-frequency words. CS-School children, who had less specified phonological representations, made a lower proportion of phonologically accurate spellings. These findings indicate that the accuracy of phonological representations, independent of the modality (acoustic versus visual) through which spoken language is perceived, determines the acquisition of phonology-to-orthography mappings. Analyses of the spelling productions indicate that the acquisition of orthographic representations of high precision depends on fully specified phonological representations.  相似文献   
189.
We investigated infants' sensitivity to amount of continuous quantity and to change in amount of continuous quantity. Using a habituation procedure, Experiment 1 examined whether 6-month-old infants can distinguish between different amounts of liquid in a container. Infants looked significantly longer at a novel quantity than at the familiar quantity. Using a violation-of-expectation paradigm, Experiment 2 examined whether 9-month-old infants expect a change in amount when liquid is added to a hidden container which is already one-fourth full of liquid. Infants looked significantly longer at the impossible event than at the possible event. These findings indicate that infants are sensitive to amount, calling into question claims that infants have a quantitative mechanism which is exclusive to number.  相似文献   
190.
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