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141.
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   
142.
In contrast to motivational accounts of the personal-group discrepancy, results from this article suggest that the discrepancy is explained by aggregating different sets of comparison outcomes for either personal or group ratings. Results from a longitudinal study with East German (the minority group) and West German (the majority group) samples confirm the personal-group discrepancy and support our approach. First, social comparisons influenced evaluations of economic situation at both group and personal levels. Second, ratings of group versus personal economic situation were based on different sets of comparisons. Third, the mean structure of both sets of comparison outcomes mirrored the personal-group discrepancy. Fourth, an interaction between personal-group discrepancy and group status supported the authors' suggestions-concerning the direction of the discrepancy.  相似文献   
143.
"Defense" and "resistance" are usually regarded as two separate and distinct concepts, the first belonging to psychic functioning in general and the second to therapy, yet this distinction is far from constant. Clinical observations indicate a frequent overlapping of these two mental functions or positions. A patient's behavior may convey the meaning of either or both concepts, and a position or response that one assumes to bespeak resistance may reveal defense instead. This state of affairs may be seen in the analysis of patients with a relatively well-integrated neurotic identity, but its main import is in the analysis of psychosomatic patients and those with severe personality disorders. Insufficient holding experiences during the infancy of these patients do not enable them to develop functional structuralization. Deficient mothering in the first stages of life also prevents the stable differentiation between defense against threats from within and resistance against influence from outside.  相似文献   
144.
145.
This article focuses on the clinical onset of obsessive-compulsive disorder (OCD), specifically addressing the age of onset, gradual and acute onset, and whether there are some types of premorbid conditions or a prodromal phase that predispose individuals to the onset of OCD. Clinical and epidemiological studies have come to different conclusions regarding age at onset as well as regarding differences between the sexes. Data gleaned from research to date have demonstrated a relationship between OCD and obsessive-compulsive personality disorder (OCPD), although OCPD does not appear to be the more prevalent personality disorder among patients with OCD. Preliminary research has suggested that Axis I disorders may predispose individuals to OCD onset; however, the significance of this relationship remains to be clarified. Evidence of the association between OCD and subthreshold obsessive-compulsive syndrome suggests that these disorders lie on a continuum of severity, with some cases developing OCD while others do not.  相似文献   
146.
The primary focus of this article is on the presentation of wisdom research conducted under the heading of the Berlin wisdom paradigm. Informed by a cultural-historical analysis, wisdom in this paradigm is defined as an expert knowledge system concerning the fundamental pragmatics of life. These include knowledge and judgment about the meaning and conduct of life and the orchestration of human development toward excellence while attending conjointly to personal and collective well-being. Measurement includes think-aloud protocols concerning various problems of life associated with life planning, life management, and life review. Responses are evaluated with reference to a family of 5 criteria: rich factual and procedural knowledge, lifespan contextualism, relativism of values and life priorities, and recognition and management of uncertainty. A series of studies is reported that aim to describe, explain, and optimize wisdom. The authors conclude with a new theoretical perspective that characterizes wisdom as a cognitive and motivational metaheuristic (pragmatic) that organizes and orchestrates knowledge toward human excellence in mind and virtue, both individually and collectively.  相似文献   
147.
Although most depressive episodes in adulthood are recurrences of the disorder, lifetime history of major depression (MD) is often neglected in predictive models. On the basis of research and theory suggesting differential prediction of MD across the course of the disorder, the authors explored whether factors that predict a first MD onset would not predict MD recurrence. Predictors of MD were examined longitudinally in a sample of 128 young women followed for 5 years. Controlling for lifetime MD history, 5-year MD was predicted by the presence before study entry of 3 variables: having witnessed family violence before age 16, having a parent with a psychiatric disorder, and having a nonmood Axis I disorder. During the follow-up period, chronic and episodic stress predicted MD. Prior lifetime MD interacted with both chronic stress and parental psychopathology to predict MD, such that first onsets, but not recurrences, were predicted by these risk variables.  相似文献   
148.
Two studies of autobiographical memory explored the hypothesis that memories become more accessible when the linguistic environment at retrieval matches the linguistic environment at encoding. In Experiment 1, Russian-English bilinguals were asked to recall specific life experiences in response to word prompts. The results supported the hypothesis of language-dependent recall: Participants retrieved more experiences from the Russian-speaking period of their lives when interviewed in Russian and more experiences from the English-speaking period of their lives when interviewed in English. In Experiment 2, the language of the interview was varied independently from the language of the word prompts. Both variables were found to influence autobiographical recall. These findings show that language at the time of retrieval, like other forms of context, plays a significant role in determining what will be remembered.  相似文献   
149.
The concreteness effect: evidence for dual coding and context availability   总被引:10,自引:0,他引:10  
The term concreteness effect refers to the observation that concrete nouns are processed faster and more accurately than abstract nouns in a variety of cognitive tasks. Two models have been proposed to explain the neuronal basis of the concreteness effect. The dual-coding theory attributes the advantage to the access of a right hemisphere image based system in addition to a verbal system by concrete words. The context availability theory argues that concrete words activate a broader contextual verbal support, which results in faster processing, but do not access a distinct image based system. We used event-related fMRI to detect the brain regions that subserve to the concreteness effect. We found greater activation in the lower right and left parietal lobes, in the left inferior frontal lobe and in the precuneus during encoding of concrete compared to abstract nouns. This makes a single exclusive theory unlikely and rather suggests a combination of both models. Superior encoding of concrete words in the present study may result from (1) greater verbal context resources reflected by the activation of left parietal and frontal associative areas, and (2) the additional activation of a non-verbal, perhaps spatial imagery-based system, in the right parietal lobe.  相似文献   
150.
Professional pianists performed 2 bimanual rhythms at a wide range of different tempos. The polyrhythmic task required the combination of 2 isochronous sequences (3 against 4) between the hands; in the syncopated rhythm task successive keystrokes formed intervals of identical (isochronous) durations. At slower tempos, pianists relied on integrated timing control merging successive intervals between the hands into a common reference frame. A timer-motor model is proposed based on the concepts of rate fluctuation and the distinction between target specification and timekeeper execution processes as a quantitative account of performance at slow tempos. At rapid rates expert pianists used hand-independent, parallel timing control. In alternative to a model based on a single central clock, findings support a model of flexible control structures with multiple timekeepers that can work in parallel to accommodate specific task constraints.  相似文献   
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