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961.
This study examined the ethnic identification, psychological well-being, and intergroup competence of biracial individuals. Using a self-identification measure, the authors explored whether biracial individuals would identify with one, both, or none of their ethnic heritages and the implications of these orientations on psychological well-being and intergroup competence. Sixty-six Black/White and Asian/White individuals were included. Not differing between the 2 biracial groups, results revealed that participants were most likely to be biculturally identified, followed by minority identified and then nonidentified. Furthermore, psychological well-being and intergroup anxiety varied as a function of identity. Suggestions for future research with biracial identity are discussed. 相似文献
962.
Research indicates that the dorsolateral prefrontal cortex (DLPFC) contributes to working memory and executive control, whereas
the ventral frontal cortex (VFC) contributes to affective and motivational processing. Few studies have examined both the
functional specificity and the integration of these regions. We did so using fMRI and a verbal working memory task in which
visual cues indicated whether recall performance on an upcoming trial would be linked to a monetary reward. On the basis of
prior findings obtained in delayed response tasks performed by nonhuman primates, we hypothesized that (1) VFC would show
an increase only in response to a cue indicating potential for a monetary reward; (2) DLPFC would show sustained activity
across a delay interval for all trials, though activity in rewarded trials would be enhanced; and (3) regions engaged in speech-based
rehearsal would be relatively insensitive to monetary incentive. Our hypotheses about DLPFC and rehearsal-related regions
were confirmed. In VFC regions, we failed to observe statistically significant effects of reward when the cue or delay epochs
of the task were examined in isolation. However, an unexpected and significant deactivation was observed in VFC during the
delay epoch; furthermore, a post hoc voxelwise analysis indicated a complex interaction between (1) the cue and delay epochs
of the task and (2) the reward value of the trials. The pattern of activation and deactivation across trial types suggests
that VFC is sensitive to reward cues, and that portions of DLPFC and VFC may work in opposition during the delay epoch of
a working memory task in order to facilitate task performance. 相似文献
963.
The effects of emotional connotation on emotional Stroop interference in anxiety were examined. First, a classical conditioning paradigm was used in which neutral words and nonwords were paired with either negative or neutral pictures. These conditioned stimuli were then presented in an emotional Stroop paradigm. Finally, participants rated each word and nonword for emotional connotation. The high-anxious group demonstrated significant interference for the nonwords that had been negatively conditioned, and these effects did not dissipate over time. The affective rating data supported the view that nonwords, but not the words had been successfully conditioned in the high-anxious group. This experiment provides evidence for the importance of emotional connotation rather than confounded semantic factors in the emotional Stroop effect. 相似文献
964.
The literature suggests that smokers are more likely to be depressed, while people who are depressed are more likely to smoke. The purpose of the present study was to determine the strength of the relationship between smoking, depression, intention to smoke, and several psychosocial and environmental factors. The participants (98 high school and college students aged 16 to 19 years) completed a paper-and-pencil questionnaire consisting of the Multiscore Depression Inventory (MDI) and items regarding smoking behavior as well as psychosocial and environmental factors. Correlation, stepwise regression, and discriminant analyses were then conducted. It was found that participants were more likely to smoke if their parents smoked, if their scores on the MDI indicated instrumental helplessness and social isolation/withdrawal, or if they were older. Participants were more likely to state intention to smoke in the future if they had MDI scores indicating instrumental helplessness, if they were older, if their parents smoked, if their MDI scores indicated social intro-version, or if they resided with a guardian. Participants were also more likely to have smoked for more years if their parents smoked or if their scores on the MDI indicated instrumental helplessness. Further, participants were more likely to have scores on the MDI indicative of higher depression levels if they had low grades or if their parents smoked. 相似文献
965.
Ditto PH Munro GD Apanovitch AM Scepansky JA Lockhart LK 《Personality & social psychology bulletin》2003,29(9):1120-1132
The quantity of processing view of motivated reasoning predicts that individuals are more likely to spontaneously question the validity of unfavorable than favorable feedback even when the objective likelihood of the feedback is equivalent. Participants were videotaped self-administering a bogus medical test revealing either a favorable or an unfavorable result. In Studies 1 and 2, unfavorable result participants required more time to accept the validity of the test result and were more likely to spontaneously recheck its validity than were favorable result participants. However, unfavorable results also were perceived as less expected than were favorable results, even though the information supplied about their objective likelihood was identical. Study 3 showed that participants evaluating another student's results perceived favorable and unfavorable outcomes as equally likely, suggesting that the subjective likelihood of positive and negative feedback is also subject to motivational influence. 相似文献
966.
Impact of executive dysfunctions on episodic memory abilities in patients with ruptured aneurysm of the anterior communicating artery 总被引:3,自引:0,他引:3
Executive and memory dysfunctions are among the most frequently reported deficits following a ruptured aneurysm of the anterior communicating artery (ACoA). In order to study the impact of the dysexecutive syndrome on episodic and semantic memory, the data obtained from 59 ACoA patients were examined retrospectively. All patients were assessed on a variety of episodic memory tests (Rey Auditory-Verbal Learning Test, Rey Complex Figure Test, Weschler Memory Scale), semantic memory (verbal fluency), and standardized tests of executive functions (Trail Making Test, Maze tests, Wisconsin Card Sorting Test). There was a strong positive correlation between executive dysfunction and retrieval difficulties in episodic and semantic memory tasks. Comparisons of subgroups of patients with high and low frontal lobe functioning on delayed recall and recognition revealed a significant group X condition interaction in addition to significant group and condition main effects. ACoAs patients with low frontal lobe functioning were particularly deficient in free recall (immediate and delayed) while recognition was equally well preserved in the two subgroups. Neither subgroup presented with an abnormal forgetting over time suggesting a retrieval deficit rather than a true retention impairment. 相似文献
967.
Sex differences exist for several cognitive tasks and estrogen has been suggested to influence these differences. Eighteen men and 18 women were matched on age and estradiol level. Potential sex differences were assessed in episodic memory, semantic memory, verbal fluency, problem solving, and visuospatial ability. Significant sex differences, favoring women, were found for tasks assessing episodic memory. Correlations between estradiol level and cognitive performance were significant for face recognition in females. Since sex differences remained in verbal episodic memory tasks and face recognition despite matched levels of estradiol, circulating estradiol does not appear to be of paramount consequence for observed sex differences in episodic memory. 相似文献
968.
The Frontal Systems Behavior Scale (FrSBe), formerly called the Frontal Lobe Personality Scale (FLOPS), is a brief behavior rating scale with demonstrated validity for the assessment of behavior disturbances associated with damage to the frontal-subcortical brain circuits. The authors report an exploratory principal factor analysis of the FrSBe-Family Version in a sample including 324 neurological patients and research participants, of which about 63% were diagnosed with neurodegenerative diseases (Huntington's, Parkinson's, and Alzheimer's diseases). The three-factor solution accounted for a modest level of variance (41%) and confirmed a factor structure consistent with the three subscales proposed on the theoretical basis of the frontal systems. Most items (83%)from the FrSBe subscales of Apathy, Disinhibition, and Executive Dysfunction loaded saliently on three corresponding factors. The FrSBe factor structure supports its utility for assessing both the severity of the three frontal syndromes in aggregate and separately. 相似文献
969.
Acquiring an understanding of design: evidence from children's insight problem solving 总被引:8,自引:0,他引:8
The human ability to make tools and use them to solve problems may not be zoologically unique, but it is certainly extraordinary. Yet little is known about the conceptual machinery that makes humans so competent at making and using tools. Do adults and children have concepts specialized for understanding human-made artifacts? If so, are these concepts deployed in attempts to solve novel problems? Here we present new data, derived from problem-solving experiments, which support the following. (i) The structure of the child's concept of artifact function changes profoundly between ages 5 and 7. At age 5, the child's conceptual machinery defines the function of an artifact as any goal a user might have; by age 7, its function is defined by the artifact's typical or intended use. (ii) This conceptual shift has a striking effect on problem-solving performance, i.e. the child's concept of artifact function appears to be deployed in problem solving. (iii) This effect on problem solving is not caused by differences in the amount of knowledge that children have about the typical use of a particular tool; it is mediated by the structure of the child's artifact concept (which organizes and deploys the child's knowledge). In two studies, children between 5 and 7 years of age were matched for their knowledge of what a particular artifact "is for", and then given a problem that can only be solved if that tool is used for an atypical purpose. All children performed well in a baseline condition. But when they were primed by a demonstration of the artifact's typical function, 5-year-old children solved the problem much faster than 6-7-year-old children. Because all children knew what the tools were for, differences in knowledge alone cannot explain the results. We argue that the older children were slower to solve the problem when the typical function was primed because (i) their artifact concept plays a role in problem solving, and (ii) intended purpose is central to their concept of artifact function, but not to that of the younger children. 相似文献
970.
The role of prosodic boundaries in the resolution of lexical embedding in speech comprehension 总被引:6,自引:0,他引:6
Participants' eye movements were monitored as they heard sentences and saw four pictured objects on a computer screen. Participants were instructed to click on the object mentioned in the sentence. There were more transitory fixations to pictures representing monosyllabic words (e.g. ham) when the first syllable of the target word (e.g. hamster) had been replaced by a recording of the monosyllabic word than when it came from a different recording of the target word. This demonstrates that a phonemically identical sequence can contain cues that modulate its lexical interpretation. This effect was governed by the duration of the sequence, rather than by its origin (i.e. which type of word it came from). The longer the sequence, the more monosyllabic-word interpretations it generated. We argue that cues to lexical-embedding disambiguation, such as segmental lengthening, result from the realization of a prosodic boundary that often but not always follows monosyllabic words, and that lexical candidates whose word boundaries are aligned with prosodic boundaries are favored in the word-recognition process. 相似文献