Working memory and behavioral inhibition in children with attention-deficit/hyperactivity disorder (ADHD): an examination of varied central executive demands,construct overlap,and task impurity

The stop-signal paradigm is the premier metric of behavioral inhibition in contemporary attention-deficit/hyperactivity disorder (ADHD) research. The stop-signal paradigm’s choice-reaction time component, however, arguably places greater demands on working memory processes (e.g., controlled-focused attention) relative to alternative inhibition metrics (i.e., go/no-go (GNG) tasks), and consequently obscures conclusions about inhibition and working memory deficits in affected children. The current study, therefore, aimed to determine whether shared variance between stop-signal behavioral inhibition and working memory performance in children with ADHD reflects overlap between the working memory and inhibition constructs or insufficient specificity of the stop-signal paradigm. Fifty-five children (8–12 years) with and without ADHD were administered established phonological (PH) and visuospatial (VS) working memory measures, as well as stop-signal and GNG tasks that vary with respect to demands on controlled-focused attention. Although working memory and GNG performance each uniquely predicted children’s inattention, stop-signal task performance was not a significant predictor of unique variance in inattention, above and beyond variance associated with working memory. Collectively, these findings suggest that performance on the stop-signal task, compared to the GNG task, is confounded by greater demands associated with working memory and consequently reflects an impure estimate of the inhibition construct.     

Social information processing skills link executive functions to aggression in adolescents with mild to borderline intellectual disability

Executive Functions (EFs) have been associated with aggression in children and adolescents. EFs as higher-order cognitive abilities are assumed to affect cognitive functions such as Social Information Processing (SIP). We explored SIP skills as a mediating mechanism linking EFs to aggression in adolescents with mild to borderline intellectual disability (MBID with IQ from 50–84), a high risk group for aggressive behaviors and EF impairments. A total of 153 adolescents (M_age = 15.24, SD = 1.35; 54% male) with MBID participated. Focused attention, behavioral inhibition, and working memory were tested with multiple neurocognitive tasks to define latent EF constructs. Participants responded to a video-based SIP task. A latent construct for aggression was defined by caretaker, teacher, and adolescent self-reports of aggression (Child Behavior Check List, Teacher Report Form, and Youth Self Report). Structural equation modeling was performed to test mediation. Results were consistent with mediation of the relation between focused attention and aggression by SIP, namely via hostile interpretations and self-efficacy for aggression. Behavioral inhibition was linked to aggression, but this relation was not mediated by SIP. The relation between working memory and aggression was mediated by SIP, namely via hostile interpretations, aggressive response generation and via self-efficacy for aggressive responses. Bearing the cross-sectional design in mind, support was found for SIP skills as a mechanism linking EFs, in particular focused attention and working memory, to aggression, providing a viable explanation for the high vulnerability of adolescents with MBID for aggression.     

前瞻记忆后效的加工机制：对自发提取观点和抑制观点的检验

摘 要 实验1探究前瞻记忆后效的产生是否消耗认知资源,实验2进一步探究前瞻记忆后效产生过程中消耗的认知资源的去向。实验1结果显示在完成阶段,相比于基线条件,其它四种实验条件的进行中任务反应速度均较慢,实验2结果显示无论线索是否显著,前瞻记忆后效均会随着认知负荷的提高而提高。结果表明前瞻记忆后效产生过程中会消耗认知资源对原意向进行抑制。本研究支持了抑制的观点。     

物质相关线索对成瘾者反应抑制的影响

成瘾者失控的物质寻求和使用与反应抑制的关系密切。很多研究在物质相关线索情境中探讨了这一关系。物质相关线索既可受到自动的注意加工, 又可诱发非自动的趋近动机状态。因此, 它们可能通过刺激驱动和状态依赖两种方式消耗有限的认知资源从而影响反应抑制, 这在成瘾行为的发展和维持中起到重要作用。未来需要在揭示其神经机制、明确物质使用动机或态度的调节、采用真实情境进行研究, 以及开发有效的干预方法等几个方面开展研究。     

自我相关信息对视觉搜索主动抑制的易化作用

工作记忆表征会以自上而下的方式调控注意选择过程, 其中一种表现就是能够对储存的干扰物表征产生注意的主动抑制, 进而提高对目标的搜索效率。另一方面, 凸显性刺激也会以自下而上的方式优先捕获注意。那么, 当保持在工作记忆中的干扰物为更具社会凸显性特征的刺激(如与自己有关的信息)时, 会对视觉搜索过程中的注意抑制产生怎样的影响, 目前尚不清楚。本研究采用短暂联结任务和工作记忆引导的视觉搜索任务范式, 探讨了自我凸显性对注意主动抑制的影响。结果发现, 相比他人和中性条件, 当工作记忆表征为自我联结刺激时, 目标搜索反应更快。本研究从行为层面为自我相关信息能够易化主动抑制过程提供了证据。     

高低创造性思维水平者的认知抑制能力：行为和生理的证据

本研究采用2个实验, 考察创造性思维测验得分高低者在Stroop任务干扰条件上的差异, 从行为和生理指标探讨认知抑制与创造性思维的关系, 以及时间压力对认知抑制与创造性思维关系的调节作用。实验1采用Stroop颜色命名任务。结果发现, 相比低创者, 高创者的反应时干扰效应量和正确率干扰效应量均更小。实验2采用更灵活的Stroop字义-颜色命名转换任务, 操纵不同的时间压力条件, 并记录被试完成任务时的皮肤电活动。结果发现, 高创者在有时间压力条件下的干扰效应量显著小于无时间压力条件下, 而低创者在有和无时间压力条件下的干扰效应量无显著差异; 高创者在颜色命名任务的不一致条件下的皮肤电活动变化显著高于一致条件, 而低创者在颜色命名任务的一致和不一致条件下无显著差异。研究表明：总体而言, 相比低创者, 高创者的认知抑制能力更高, 能够有效抑制优势的但不相关的反应倾向。时间压力在认知抑制与创造性思维的关系中起调节作用, 高创者面对不同任务要求能够灵活调整自身的认知抑制水平, 并表现出变化的生理唤醒水平。结果支持创造性思维的适应性认知抑制假说。     

抑制对老年人舌尖现象的影响

抑制不足理论认为老年人抑制能力不足, 易受干扰信息的影响, 阻碍对目标词的检索, 故比年轻人有更多舌尖现象。实验1操纵抑制通达子功能探讨其在老年人舌尖现象中的作用, 采用2(干扰条件：有、无)×2(年龄组：老年、年轻)的混合设计, 相比于无干扰条件, 干扰条件下舌尖现象年龄差异变得更大, 表明老年人舌尖现象和通达功能有关。实验2操纵抑制删除子功能, 采用2(是否激活干扰：是、否)×2(年龄组：老年、年轻)的混合设计, 不激活干扰条件下舌尖现象年龄差异不显著, 而激活干扰条件下舌尖现象年龄差异显著, 舌尖现象随龄增多与删除功能不足有关。通达和删除功能不足是老年人舌尖现象增多的重要原因。     

情绪对不同外倾水平个体行为抑制的影响

采用双选择oddball实验范式与事件相关电位（ERP）技术,探讨了情绪对行为抑制的影响以及外倾性的调节作用。行为数据发现,相比标准刺激,被试对偏差刺激的反应时显著更慢,证明实验成功诱发了行为抑制效应。在内倾组,负性刺激下偏差与标准刺激反应时差值显著长于正性刺激条件,而在外倾组无显著差异。脑电数据发现,在N2成分上,内倾组在正性情绪下的波幅显著小于负性和中性情绪,而在外倾组,不同情绪下的波幅不存在显著差异。在P3成分上,内倾组在正性情绪下的波幅显著大于负性和中性情绪,相反,外倾组在负性情绪下的波幅显著大于正性和中性情绪。结果表明,情绪对行为抑制的影响受到了个体外倾性水平的调节。     

不同熟练双语儿童注意定向中的抑制控制

研究目的：探讨不同熟练双语儿童“注意定向”成分中抑制控制的差异,及这一差异是否依赖于双语儿童第二语言的熟练程度。方法：采用IOR范式的行为实验。被试为平衡、未平衡双语儿童和单语儿童。结果：SOA600ms时,三组被试均出现了IOR,平衡双语儿童与单语儿童的IOR效应量差异显著,其余被试间差异均不显著。结论：（1）双语学习促进了平衡双语儿童抑制控制能力的发展。（2）双语学习对抑制控制能力的促进作用依赖于双语儿童第二语言的熟练程度。     

Task‐related interactions between kindergarten children and their teachers: the role of emotional security

This study examined the emotional security of kindergarten children in dyadic task‐related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers' support. Participants were 79 kindergartners (mean age=69.7 months) and their 40 regular teachers. Children were selected to approach a normal distribution of social inhibition. Children and teachers were filmed during a dyadic interaction task outside the classroom. Three groups of independent observers rated children's emotional security and their task behaviours, as well as teachers' supportive behaviours. Multilevel modelling revealed a positive link between teachers' support and emotional security. This link suppressed a negative relation between social inhibition and emotional security. In addition, emotional security was positively associated with children's task behaviours and mediated part of the positive link between these behaviours and teachers' support. Finally, security moderated the relation between support and persistence, such that the effect of teachers' support on persistent behaviours was amplified for relatively insecure children. These results highlight the importance of considering emotional security when examining the interactions between kindergarten children and their teachers. Copyright © 2008 John Wiley & Sons, Ltd.