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191.
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
192.
Maienschein J 《The American journal of bioethics : AJOB》2002,2(1):12-9, 30
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
193.
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
194.
Eichstaedt J 《Experimental psychology》2002,49(4):283-291
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
195.
Leybaert J 《Journal of experimental child psychology》2000,75(4):291-318
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
196.
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
197.
198.
The present study examined whether gender differences in affiliative aspects (collaboration and cooperation) of dyadic conversations occur because girls are more oriented than boys toward goals focused on others. Preadolescents (11-13 years old; 51 boys, 53 girls) worked with a same- or an other-gender peer on a 4-week-long creative-writing task at school. Dyadic conversations and goals were assessed twice. High-affiliation conversations and mutual-participation goals were more prevalent in female than in male and mixed-gender dyads. Mutual-participation goals mediated gender differences in high-affiliation conversations. Control and task-performance goals did not differ by dyad gender. In mixed-gender dyads, conversation strategies and goals did not differ by gender. Implications of goals for understanding gender differences and similarities in conversations are discussed. 相似文献
199.
Conceptual structure and social functions of behavior explanations: beyond person--situation attributions 总被引:3,自引:0,他引:3
Malle BF Knobe J O'Laughlin MJ Pearce GE Nelson SE 《Journal of personality and social psychology》2000,79(3):309-326
The traditional approach to studying behavior explanations involves treating them as either person causes or situation causes and assessing them by using rating scales. An analysis of people's free-response behavior explanations reveals, however, that the conceptual distinctions people use in their explanations are more complex and sophisticated than the person-situation dichotomy suggests. The authors, therefore, introduce a model of the conceptual structure of folk behavior explanations (the network of concepts and assumptions on which explanations are based) and test it in 4 studies. The modes and features of behavior explanations within this conceptual structure also have specific social functions. In 2 additional studies, the authors demonstrate that people alter distinct features of their explanations when pursuing particular impression-management goals and that listeners make inferences about explainers' goals on the basis of these features. 相似文献
200.
The authors propose that the nonaffective bodily feedback produced by arm flexion and extension informs individuals about the processing requirements of the situation, leading to the adoption of differential processing styles and thereby influencing creativity. Specifically, the authors predicted that arm flexion would elicit a heuristic processing strategy and bolster insight processes, whereas arm extension would elicit a systematic processing strategy and impair insight processes. To test these predictions, the authors assessed the effects of these motor actions on 3 central elements of creative insight: contextual set-breaking, restructuring, and mental search. As predicted, in 6 experiments, arm flexion, relative to arm extension, facilitated insight-related processes. In a 7th experiment, arm extension, relative to arm flexion, facilitated analytical reasoning, supporting a cognitive tuning interpretation of the findings. 相似文献