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981.
The present study was designed to examine the role that attentional problems may play in accounting for difficulties in story comprehension experienced by children with ADHD. A secondary task methodology was used to examine whether or not online variations in cognitive engagement with a televised story were related to the continuity of central or incidental information. Twenty-two 9- to 11 -year-old boys with ADHD and 36 of their nonreferred peers watched a television program and responded to auditory probes presented at preselected points during continuous sequences of central or incidental information. The reaction times to the probes for nonreferred boys showed the expected linear increase in cognitive engagement (i.e., the RTs increased) as central, plot-relevant sequences continued. In contrast, boys with ADHD showed the expected increase in RTs relatively late in the central sequences. The results were discussed in terms of how delays in engaging with central information may contribute to the academic difficulties experienced by boys with ADHD. 相似文献
982.
Recent research has indicated that the pro-inflammatory cytokines, particularly interleukin-1beta (IL-1beta), can affect learning and memory. We injected male Sprague-Dawley rats with IL-1beta (1.0, 3.0, or 6.0 microg/kg, i.p.) or saline vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. No effect of IL-1beta at any dose was observed in the number of escape responses across the 4-h session. However, subjects treated with the two lower doses (1.0 and 3.0 microg/kg) of IL-1beta performed more avoidance responses during the final hour of the 4-h session than the other two groups. Subjects treated with the highest dose of IL-1beta (6.0 microg/kg) did not differ from controls. Results are discussed in terms of the possible mechanisms behind the IL-1beta-induced enhancement of learning, as well as the observed dose-response relationship. 相似文献
983.
The present paper examines the role of cognitive-behavioral therapy (CBT) in the treatment of social anxiety disorder (SAD). A cognitive-behavioral model of SAD is first presented. Different modalities of CBT for SAD are then described, including exposure, cognitive restructuring, relaxation training, and social skills training, and evidence supporting their efficacy is reviewed. The comparative and combined impact of CBT and pharmacotherapeutic interventions is also explored. CBT appears to be an efficacious treatment for SAD. However, the overall efficacy CBT may be increased by closer examination of the active ingredients of treatment. Such analyses may also enable more successful integration of the different CBT techniques and of CBT and pharmacotherapy in the treatment of SAD. 相似文献
984.
985.
Electrophysiological correlates of anterior cingulate function in a go/no-go task: Effects of response conflict and trial type frequency 总被引:1,自引:0,他引:1
Nieuwenhuis S Yeung N van den Wildenberg W Ridderinkhof KR 《Cognitive, affective & behavioral neuroscience》2003,3(1):17-26
Neuroimaging and computational modeling studies have led to the suggestion that response conflict monitoring by the anterior cingulate cortex plays a key role in cognitive control. For example, response conflict is high when a response must be withheld (no-go) in contexts in which there is a prepotent tendency to make an overt (go) response. An event-related brain potential (ERP) component, the N2, is more pronounced on no-go than on go trials and was previously thought to reflect the need to inhibit the go response. However, the N2 may instead reflect the high degree of response conflict on no-go trials. If so, an N2 should also be apparent when subjects make a go response in conditions in which nogo events are more common. To test this hypothesis, we collected high-density ERP data from subjects performing a go/no-go task, in which the relative frequency of go versus no-go stimuli was varied. Consistent with our hypothesis, an N2 was apparent on both go and no-go trials and showed the properties expected of an ERP measure of conflict detection on correct trials: (1) It was enhanced for low-frequency stimuli, irrespective of whether these stimuli were associated with generating or suppressing a response, and (2) it was localized to the anterior cingulate cortex. This suggests that previous conceptions of the no-go N2 as indexing response inhibition may be in need of revision. Instead, the results are consistent with the view that the N2 in go/no-go tasks reflects conflict arising from competition between the execution and the inhibition of a single response. 相似文献
986.
The nature of the association between anger and 5 appraisal-action tendency components--goal obstacle, other accountability, unfairness, control, and antagonism--was examined in terms of specificity, necessity, and sufficiency. In 2 studies, participants described recently experienced unpleasant situations in which 1 of the appraisal-action tendency components was present or absent and indicated which emotions they had experienced. The results showed that (a) other accountability and arrogant entitlement, as an instance of unfairness, are specific appraisals ability for anger; and most important, (b) none of the components is necessary or sufficient for anger. The findings suggest that the relation between emotions and appraisal-action tendency components should be conceptualized instead as a contingent association, meaning that they usually co-occur. 相似文献
987.
988.
Merijn?van?TilborgEmail author Jan?N.?C.?van der?Pers Peter?Roessingh Maurice?W.?Sabelis 《Behavior research methods》2003,35(3):478-482
A novel type of locomotion compensator was designed and tested for its use in orientation behavior experiments with a predatory mite. In this apparatus, displacements of the test animal in the two-dimensional plane are recorded using video equipment and a servosphere that keeps the animal in focus. Thex andy displacements are registeredusing two rotation encoders and are compensated using a pair of servo-motors, in such a way that the animal is always positioned on top of the sphere, yet moves freely. Well-fed and starved predators were tested for their responses to (1) still air, (2) a stimulus-free air flow, (3) an air flow with odors from uninfested Lima bean leaves, and (4) an air flow with odors from Lima bean leaves infested by plant-feeding mites, the prey of the predatory mites. Anemotactic responses of adultPhytoseivlus persimilis females were feeding state dependent. Well-fed predators moved downwind under Treatments 1–3 but moved neither up-nor downwind in the presence of odors from infested plants (Treatment 4). Starved predators moved upwind under all treatments. These results are in agreement with those of earlier studies in a wind tunnel, and therefore, the new type of locomotion compensator (LC-100) offers an excellent method for studying the orientation behavior of micro-arthropods. 相似文献
989.
990.