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991.
Males of the Rb/lBg and C57BL/10Bg strains, as well as of the Bl0RblF, and RblBlOF1, reciprocal hybrids, were tested for aggression over three daily trials beginning at 50 days of age. The BlORblF, hybrids were sired by Rb/lBg males, and the RblBlOF, hybrids were sired by C57BL/10Bg males. The mean scores for the agonistic acts of chase, wrestle, flank-bite (but not tail rattle or attack), and the mean “aggression” score (but not mean latencies to first agonistic act or first attack) were significantly higher for BlORblF, than for RblBlOF, hybrids. These findings are consistent with the hypothesis that some aspect(s) of the Rb/lBg Y-chromosome strain can influence the occurrence of some of the motor patterns of offense but not defense. The Y-chromosomes of the DBA/1, DBA/2, CBA, and PHH inbred strains have a similar effect on agonistic behaviors. 相似文献
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Nanda N. J. Rommelse Marieke E. Altink Ellen A. Fliers Neilson C. Martin Cathelijne J. M. Buschgens Catharina A. Hartman Jan K. Buitelaar Stephen V. Faraone Joseph A. Sergeant Jaap Oosterlaan 《Journal of abnormal child psychology》2009,37(6):793-804
We aimed to assess which comorbid problems (oppositional defiant behaviors, anxiety, autistic traits, motor coordination problems,
and reading problems) were most associated with Attention-Deficit/Hyperactivity Disorder (ADHD); to determine whether these
comorbid problems shared executive and motor problems on an endophenotype level with ADHD; and to determine whether executive
functioning (EF)—and motor-endophenotypes supported the hypothesis that ADHD with comorbid problems is a qualitatively different
phenotype than ADHD without comorbid problems. An EF—and a motor-endophenotype were formed based on nine neuropsychological
tasks administered to 816 children from ADHD—and control-families. Additional data on comorbid problems were gathered using
questionnaires. Results indicated that oppositional defiant behaviors appeared the most important comorbid problems of ADHD,
followed by autistic traits, and than followed by motor coordination problems, anxiety, and reading problems. Both the EF—and
motor-endophenotype were correlated and cross-correlated in siblings to autistic traits, motor coordination problems and reading
problems, suggesting ADHD and these comorbid problems may possibly share familial/genetic EF and motor deficits. No such results
were found for oppositional defiant behaviors and anxiety. ADHD in co-occurrence with comorbid problems may not be best seen
as a distinct subtype of ADHD, but further research is warranted.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
993.
Kevin J. MacDonald Holly A. Lockhart Alex C. Storace Stephen M. Emrich Kimberly A. Cote 《Cognitive, affective & behavioral neuroscience》2018,18(6):1105-1120
Working memory (WM) is impaired following sleep loss and may be improved after a nap. The goal of the current study was to better understand sleep-related WM enhancement by: (1) employing a WM task that assesses the ability to hold and report visual representations as well as the fidelity of the reports on a fine scale, (2) investigating neurophysiological properties of sleep and WM capacity as potential predictors or moderators of sleep-related enhancement, and (3) exploring frontal and occipital event-related delay activity to index the neural processing of stimuli in WM. In a within-subjects design, 36 young adults (Mage = 20, 20 men, 16 women) completed a 300-trial, continuous-report task of visual WM following a 90-min nap opportunity and an equivalent period of wakefulness. Mixed-effect models were used to estimate the odds of successful WM reports and the fidelity of those reports. The odds of a successful report were approximately equal between nap and wake conditions for the start of the task, but by the end, the odds of success were 1.26 times greater in the nap condition. Successful WM reports were more accurate after a nap, independent of the time on task. Neither WM capacity nor any of the sleep variables measured were found to significantly moderate the nap effect on WM. Lastly, napping resulted in amplitude changes for frontal and occipital delay activity relative to the wake condition. The findings are discussed in relation to contemporary models of visual WM and the role of sleep in sustained attention. 相似文献
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