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Brain mapping studies using dynamic imaging methods demonstrate areas regional cerebral blood flow (rCBF) decreases, as well as areas where increases, during performance of various experimental tasks. Task holds for both sets of cerebral blood flow changes (CBF), providing the opportunity to investigate areas that become and “activated” in the experimental condition relative to control state. Such data yield the intriguing observation that in areas in emotional processing, such as the amygdala, the posteromedial cortex, and the ventral anterior cingulate cortex, although flow as expected during specific emotion-related tasks, flow decreases performance of some attentionally demanding, cognitive tasks. Conversely, in some of the areas that appear to subserve cognitive functions, as the dorsal anterior cingulate and the dorsolateral prefrontal cortices, increases while performing attentionally demanding cognitive tasks, but during some experimentally induced and pathological emotional Although the specific nature of such reciprocal patterns of regional remains unclear, they may reflect an important cross-modal interaction during mental operations. The possibility that neural activity is less in areas required in emotional processing during some higher cognitive processes holds implications for the mechanisms underlying interactions cognition and emotion. Furthermore, the possibility that neural in some cognitive-processing areas is suppressed during intense states suggests mechanisms by which extreme fear or severe may interfere with cognitive performance.  相似文献   
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Population attributable risk (PAR) estimates have been used in suicide research to evaluate the impact of psychosocial and socioeconomic risk factors, including affective disorders, traumatic life events, and unemployment. A parallel concept of preventive fraction (PF), allowing for estimation of the impact of protective factors and effectiveness of preventive interventions, is practically unknown in suicidology. The study authors discuss the application of both concepts to suicide research and prevention, and review literature on the subject. Despite several methodological and conceptual limitations, both PAR and PF are valuable instruments to inform development and evaluation of suicide prevention programs.  相似文献   
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An eye-tracking experiment investigated whether incremental interpretation applies to interclausal relationships. According to Millis and Just's (1994) delayed-integration hypothesis, interclausal relationships are not computed until the end of the second clause, because the processor needs to have two full propositions before integration can occur. We investigated the processing of causal and diagnostic sentences (Sweetser, 1990; Tversky & Kahneman, 1982) that contained the connective because . Previous research (Traxler, Sanford, Aked, & Moxey, 1997) has demonstrated that readers have greater difficulty processing diagnostic sentences than causal sentences. Our results indicated that difficulty processing diagnostic sentences occurred well before the end of the second clause. Thus comprehenders appear to compute interclausal relationships incrementally.  相似文献   
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Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations.  相似文献   
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ABSTRACT The construct validity of assertion was analyzed in three independent correlational studies The convergence of self-reported, laboratory roleplayed, self-observed, and peer-rated measures was examined, as well as their relationship to Norman's peer-rated five personality factors of extraversion, agreeableness, conscientiousness, emotional stability, and culture Twenty-three and 29 undergraduate students participated in Studies 1 and 2, respectively In general, results showed poor convergence among assertiveness measures even when increasing the representativeness and reliability of the role-played laboratory and self-observed measures, as in Study 2 In Study 3, the role-playing test was abandoned and 45 subjects served as peers for one another The results of Study 3 supported the prediction that assertiveness measures showed at least moderate convergence, in addition there were significant relationships between assertiveness and extraversion and between peer-rated assertiveness and agreeableness, conscientiousness, and culture The relative contribution of each assessment procedure to the construct validity of assertion is discussed  相似文献   
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The influences of sex, age, and conversational, partner (mother vs. stranger) on eye contact during verbalizations were examined in a longitudinal study of 33 children at 2 and 4 years of age. A free-play sample was obtained of each child interacting with mother and with a male or female experimenter. The amount of eye contact in conjunction with verbalization was analyzed. Significant main effects were found for sex (females engaged in a higher percent of eye contact than males) and conversational partner (more eye contact while speaking exhibited to experimenter than to mother). There was an interaction between age and conversational partner, in that mother received more and experimenter relatively less percent of eye contact during verbalizations as children got older. Notably, there was no main effect for age. These results revealed sex differences at an age (2–2 1/2 years) and in a context (free-play setting) not previously studied, demonstrating the robustness of the effect. Further, age findings seem indicative of unique developmental trends for eye contact during verbalizations for the ages between 2 and 4 years.Mount Saint Vicent University  相似文献   
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An experiment that examined the way in which young readers deployed eye movements while reading sentences and while answering questions containing either a pronominal or noun anaphor is reported. To evaluate the possible causal role played by differences in inspection strategies between readers of above- and below-average reading skill, a third“age control” group of younger children was also tested. This group was matched on absolute reading ability with the less skilled group of older children, and on relative reading ability (i.e. reading quotient) with the more skilled group. Differences in inspection strategy were apparent between the groups of good and poor readers. Good readers launched more selective reinspections, whereas the poorer readers were more inclined to engage in“backtracking” and appeared to make less use of the displayed text. In every case there was a marked similarity in the behaviour of the good readers and the“age controls”. These results suggest that the ability to code the spatial location of words in a sentence, and, where necessary, to use this information to launch accurately targetted selective reinspections of previously read text, plays a crucial role in the development of skilled reading performance.  相似文献   
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