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Attention capacity and task difficulty in visual search 总被引:1,自引:0,他引:1
When a visual search task is very difficult (as when a small feature difference defines the target), even detection of a unique element may be substantially slowed by increases in display set size. This has been attributed to the influence of attentional capacity limits. We examined the influence of attentional capacity limits on three kinds of search task: difficult feature search (with a subtle featural difference), difficult conjunction search, and spatial-configuration search. In all 3 tasks, each trial contained sixteen items, divided into two eight-item sets. The two sets were presented either successively or simultaneously. Comparison of accuracy in successive versus simultaneous presentations revealed that attentional capacity limitations are present only in the case of spatial-configuration search. While the other two types of task were inefficient (as reflected in steep search slopes), no capacity limitations were evident. We conclude that the difficulty of a visual search task affects search efficiency but does not necessarily introduce attentional capacity limits. 相似文献
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A meta-analytic review of stopping performance in attention-deficit/hyperactivity disorder: deficient inhibitory motor control? 总被引:14,自引:0,他引:14
Lijffijt M Kenemans JL Verbaten MN van Engeland H 《Journal of abnormal psychology》2005,114(2):216-222
This review discusses whether deficient inhibitory motor control is the core deficit of attention-deficit/hyperactivity disorder (ADHD). Inhibitory motor control is commonly assessed using the stop-signal paradigm. Since the last meta-analysis that was performed, 33 new studies have appeared. The current meta-analysis revealed a significant difference between ADHD patients and matched controls in stop latency (stop-signal reaction time) in both children and adults. Basic reaction time was significantly longer in children with ADHD, but not in adults, and there was a significant interaction between the elongation of the latency to stop and to respond in adults, but not in children. Deficient inhibitory motor control may be less crucial in children than in adults with ADHD. 相似文献
139.
Tronick EZ Messinger DS Weinberg MK Lester BM Lagasse L Seifer R Bauer CR Shankaran S Bada H Wright LL Poole K Liu J 《Developmental psychology》2005,41(5):711-722
Prenatal cocaine and opiate exposure are thought to subtly compromise social and emotional development. The authors observed a large sample of 236 cocaine-exposed and 459 nonexposed infants (49 were opiate exposed and 646 nonexposed) with their mothers in the face-to-face still-face paradigm. Infant and maternal behaviors were microanalytically coded. No opiate-exposure effects were detected. However, mothers of cocaine-exposed infants showed more negative engagement than other mothers. The cocaine-exposed dyads also showed higher overall levels of mismatched engagement states than other dyads, including more negative engagement when the infants were in states of neutral engagement. Infants exposed to heavier levels of cocaine showed more passive-withdrawn negative engagement and engaged in more negative affective matching with their mothers than other infants. Although effect sizes were small, cocaine exposure, especially heavy cocaine exposure, was associated with subtly negative interchanges, which may have a cumulative impact on infants' later development and their relationships with their mothers. 相似文献
140.
One of the most frequently reported changes across the transition to parenthood is a decline in marital quality after the birth of a first baby. Experiences in the family of origin may influence the trajectory of marital quality. Our study aimed to investigate the impact of recollections of family-of-origin marriage on marital quality (self-reports and clinical evaluation) from pregnancy to 1 year after the birth of a first child. A total of 62 first-time parents completed questionnaires (self-reported marital satisfaction) and clinical interviews (clinical evaluation of couples' dialogue quality). Although self-reported marital satisfaction and observed dialogue quality were highly associated, only self-reported marital satisfaction declined from pregnancy to 1 year after birth. This decrease was partly due to very high marital satisfaction during pregnancy. Different trajectories for self-reported marital satisfaction and observed dialogue quality were found for participants with recollections of low-, average-, and high-quality family-of-origin marriage. A structural equation model showed that participants who recollected a negative quality in their parents' relationship reported more negative changes in the quality of their own marriages. There seems to be an intergenerational transmission of marital quality that comes to light when couples are challenged by the birth and rearing of a baby. 相似文献