钟面画测试及其在ADHD儿童中的研究

钟面画测试被广泛用于研究和测试老年人群中的各种认知缺陷和认知老化,是一种有用的筛选老年痴呆症病人的工具。近年来它也被用于研究正常儿童和ADHD儿童。该文回顾了钟面画测试所涉及的内部认知过程以及影响钟面画测试的各种因素、钟面画测试与执行功能测试之间的相关,并且重点回顾了钟面画测试在正常儿童和ADHD儿童中的研究。由于钟面画测试本身简便、快捷,可以迅速地大规模筛选障碍儿童,在这方面的研究具有重大的实践意义。     

任务切换中切换代价产生的机制

关于任务切换中切换代价的来源和本质,目前主要有三种观点:任务设置惯性、任务设置重构和联结竞争。为揭示三者的关系,研究了在不同延迟时间条件下,预先信息与刺激类型对切换代价的影响机制。结果发现:延迟时间、预先信息和刺激类型对切换代价均有显著的作用,但是,三者之间的二次和三次交互作用均不显著。这表明,切换代价反映了任务设置惯性、任务设置重构和联结竞争三种成分,并且三者的关系是具有可加性的序列认知加工。     

任务维度和任务无关维度干扰信息的同质性影响视觉搜索的神经机制

在三个实验中, 我们利用功能性磁共振成像(functional magnetic resonance imaging, fMRI)技术考察了在简单特征搜索任务和客体内联合搜索任务中任务维度干扰项的同质性(或称一致性, homogeneity)和任务无关维度干扰信息的同质性对视觉搜索行为的影响及其神经机制。主要探讨了三个问题：(1) 任务维度干扰信息的同质性与目标存在性之间交互作用的神经机制; (2) 任务维度干扰信息的同质性与任务无关维度干扰信息的同质性之间的交互作用及其神经机制; (3) 上述神经机制在不同类型的视觉搜索(特征搜索和联合搜索)中的异同。     

两种亚型ADHD儿童在停止信号任务中的反应抑制

采用停止信号任务,操纵其中的反应冲突,探查两种亚型（注意缺陷型和混合型）ADHD儿童在不同抑制功能——反应冲突和反应停止上的表现,以及儿童在内源性和外源性两种注意条件下反应抑制的表现。结果发现,与正常儿童相比,ADHD儿童在两种反应抑制上都有不同程度的缺损,不仅冲突效应量更大,反应停止的错误率也更高;但在控制年龄因素后,未观察到两种亚型ADHD儿童之间在反应冲突和反应停止能力上有明显差异。研究还发现,儿童在内源性和外源性两种注意条件下反应抑制的表现模式相似,说明反应冲突和反应停止可能存在某些共同的神经机制,两种亚型ADHD儿童在这些机制的功能缺损上有类似之处。     

任务切换理论争议新证据

任务切换是研究认知控制的主要范式之一。大量研究发现切换试次比重复试次的反应时更长,错误率更高,这种差异称为切换代价。任务切换时所产生切换代价的理论解释主要有惯性论、重构论和联结论。近十年来,这些理论均获得新的实验支持和发展,但其争议依旧,没有哪一理论能成功解释任务切换的所有效应。未来研究可以建立整合模型,以准确描述切换代价产生的认知机制。     

准备时间和预先信息对任务切换的影响

两个实验采用任务线索范式,考察了准备时间和预先信息对任务切换的影响。实验1的准备时间为可预测,实验2的为不可预测,以考察准备时间的可预测性对任务切换的影响。以被试执行重复任务、切到任务和切离任务的正确反应时为主要指标,结果：（1）在准备时间可预测和不可预测两种条件下,准备时间和预先信息之间存在显著交互作用。在可预测条件中,重复和切到任务的反应时随着准备时间的增加而减少,但切到代价无显著变化,切离任务的反应时不受准备时间的影响,切离代价表现出反准备效应;不可预测条件下,三种任务的反应时都随着准备时间的增加而减少,但是切到和切离代价表现出反准备效应;（2）切离任务的反应时和代价显著高于切到任务的反应时和代价;（3）在这两种条件下,都没有出现切换代价的准备效应     

执行控制研究的重要范式——任务切换

任务切换是当前研究执行控制的重要范式。被试完成切换任务要慢于完成重复任务,并且往往有更高的错误率,这种差异称为切换损失。该文对此领域的研究进行了回顾,介绍了任务切换研究范式的发展,重点阐述了对切换损失来源的三种主要解释：任务重建、联结竞争和任务设置的惯性;指出任务切换与其他范式的结合是更深入地了解执行控制的可行途径。最后进行了简要的总结与展望。     

延迟时间与预先信息对任务切换的作用

对切换代价的本质存在任务设置惯性和任务设置重构两种观点。为揭示二者在切换代价中的关系, 研究了不同延迟时间条件下预先信息对任务切换的作用, 结果发现：(1)延迟时间对切换代价有显著影响, 100 ms的切换代价显著高于1000 ms的切换代价, 而600 ms分别与100 ms、1000 ms之间的切换代价无显著差异; (2)预先信息对切换代价的影响显著, 全部信息的切换代价显著低于无信息和部分信息的切换代价, 而后二者之间无显著差异; (3)延迟时间与预先信息无交互作用。这表明, 延迟时间与预先信息分别作用于任务设置惯性和任务设置重构, 切换代价反映了这两种具有相加效应的加工过程。     

刺激类型与预先信息对任务切换的影响

为揭示联结竞争与任务设置重构在切换加工过程中的关系,以切换代价为指标,研究了刺激类型与预先信息对任务切换的影响效应,结果发现:(1)无信息的切换代价显著高于部分信息和全部信息的切换代价,而后二者之间无显著差异;(2)单向刺激的切换代价显著高于双向刺激的切换代价;(3)预先信息和刺激类型对切换代价的影响无交互作用。这表明任务设置重构与联结竞争是两个具有相加效应的序列认知活动。     

任务切换的老化效应

采用任务线索范式(task-cueing paradigm),考察年龄对两个不同来源的切换损失的影响。实验一操控准备时间考察内源性切换损失,实验二操控首尾任务的异同考察外源性切换损失。以被试执行切换任务和重复任务的正确反应时为主要指标,结果发现:(1)在执行不同类型的任务时,老化效应极其明显,青年人反应速度普遍快于老年人,错误率普遍低于老年人;(2)内源性任务范式中重复任务和切换任务老化速度不一致,老化对切换任务影响更大,而外源性任务范式中CBA和ABA任务老化速度基本一致;(3)青年人和老年人在内源切换损失、外源切换损失上不存在显著差异。结果表明,整体上老年人的任务切换成绩差于年轻人,与外源性任务相比,内源性切换任务的成绩更易受老化的影响。     

Task Switching and Attention Deficit Hyperactivity Disorder

The main goal of the present set of studies was to examine the efficiency of executive control processes and, more specifically, the control processes involved in task set inhibition and preparation to perform a new task in attention deficit hyperactivity disorder (ADHD) and non-ADHD children. This was accomplished by having ADHD children, both on and off medication, and non-ADHD children perform the task-switching paradigm, which involves the performance of two simple tasks. In nonswitch trials, an individual task is performed repeatedly for a number of trials. In switch trials, subjects must rapidly and accurately switch from one task to the other, either in a predictable or unpredictable sequence. Switch costs are calculated by subtracting performance on the nonswitch trials from performance on the switch trials. These costs are assumed to reflect the executive control processes required for the coordination of multiple tasks. ADHD children showed substantially larger switch costs than non-ADHD children. However, when on medication, the ADHD children's switch performance was equivalent to control children. In addition, medication was observed to improve the ADHD children's ability to inhibit inappropriate responses. These data are discussed in terms of models of ADHD and cognition.     

Interference Control in Children with Attention Deficit/Hyperactivity Disorder

The view that Attention Deficit/Hyperactivity Disorder (ADHD) is associated with a diminished ability to control interfference is controversial and based exclusively on results of (verbal)-visual interference tasks, primarily the Stroop Color Word task. The present study compares medication-naïve children with ADHD (n?=?35 and n?=?51 in Experiments 1 and 2, respectively) with normal controls (n?=?26 and n?=?32, respectively) on two interference tasks to assess interference control in both the auditory and the visual modality: an Auditory Stroop task and a Simon task. Both groups showed reliable but equal degrees of interference on both tasks, suggesting that children with ADHD do not differ from normal controls in their ability to control interference in either modality.     

错误意识判断对ADHD儿童错误觉察的影响特点

将GO/NO-GO任务范式和错误意识判断范式相结合,对21名ADHD儿童,27名正常儿童,在错误监控中的错误觉察水平进行考察,结果表明:1)ADHD儿童能够正常觉察到自己的错误反应;2)错误意识判断任务诱发出ADHD儿童的错误延迟效应,这种作用,既是因为该任务能够刺激ADHD儿童的有意觉察,又因为该任务无形中增加了GO/NO-GO任务中的刺激间隔时间。该结果表明,增加刺激间隔时间,可能会促使ADHD儿童改变错误后的反应策略,对错误反应进行错误调节,提高其错误监控水平。     

The Development of Selective Attention in Children With Attention Deficit Hyperactivity Disorder

The influence of age on a selective attention task was studied in a sample of children with and without Attention Deficit Hyperactivity Disorder (ADHD). The impact of methylphenidate (MPH) treatment on selective attention was also investigated in the children with ADHD. Two age groups of children with ADHD and two age groups of control children were tested using a timed computer task. The task consisted of identifying visual target stimuli under various distracter conditions. Distracters varied on the basis of modality (i.e., visual, auditory, or both) and task relevance (i.e., meaningful or irrelevant). Reaction times and accuracy were measured. Children with ADHD were less efficient on the selective attention task than were children without ADHD, and older children were more efficient than younger children in both groups. Children without ADHD were influenced more by the nature of distracters than were children with ADHD. For children with ADHD, MPH improved performance overall.     

反馈对注意缺损多动障碍儿童错误监控能力的影响

研究选取了注意缺损多动障碍(ADHD)儿童39名,正常儿童40名,采用两项选择任务,考察在无反馈和有反馈的情况下,ADHD儿童的错误监控能力是否存在缺损。结果发现,(1)无论是否提供反馈,与正常儿童相比,ADHD儿童的错误察觉能力正常,但是错误更正能力落后,这可能是由于ADHD儿童动作调节控制能力落后导致的;(2)反馈提高了ADHD儿童和正常儿童的认知加工速度,但同时降低了他们的警醒水平,导致错误监控能力下降。     

Psychosocial Treatments for Children with Attention Deficit/Hyperactivity Disorder

This article reviews studies examining the efficacy of behavioral interventions for the treatment of attention-deficit/hyperactivity disorder (ADHD). A specific emphasis is placed on evidence-based interventions that include parent training, classroom, academic, and peer interventions. Results indicate that school-aged children respond to behavioral interventions when they are appropriately implemented both at home and in the classroom setting. Combined treatments (behavioral management and stimulant medication) represent the gold standard in ADHD treatment and are often recommended as the first-line treatment option due to the many problems faced by children with ADHD. Diversity issues, although an important consideration in the treatment of ADHD, continue to remain an understudied area. Recommendations for future research are made pertaining to treatment sequencing with regard to behavior management as well as for subgroups of ADHD children who may respond best to specific treatments.     

工作记忆负荷对注意缺陷多动障碍儿童过滤新异分心刺激能力的影响*

关于启动工作记忆负荷的强度与过滤分心刺激这两种认知资源的关系一直存在争论;并且对ADHD儿童来说,新异的分心刺激是提高了唤醒水平,还是干扰了任务进程也一直存在争论。本研究选取了ADHD儿童32名,正常儿童35名。采用视听跨通道oddball任务,通过操作视觉任务工作记忆负荷的高低,以及分心刺激与目标刺激之间的时间间隔,探讨不同工作记忆负荷对 ADHD 儿童过滤新异分心刺激能力的影响。结果发现：(1)在低工作记忆负荷条件下,分心刺激对两组儿童都起到了唤醒作用;在高工作记忆负荷条件下,分心刺激影响了两组儿童对任务本身的加工过程,使其判断的精确性下降。但是 ADHD 儿童受到的影响更大,表明其过滤分心刺激的能力落后。(2)当分心刺激与目标刺激同时出现时, ADHD儿童受到的干扰最大;但随着二者时间间隔的延长,并没有出现间隔越长干扰效应越小的趋势。在本研究条件下,得出以下结论：(1)两组儿童对跨通道新异分心刺激的过滤受到目标任务的工作记忆负荷强度的影响。(2)适度延长分心刺激与目标刺激之间的时间间隔可能会帮助ADHD的注意回归。     

注意缺陷多动障碍儿童的表征搜索

为探索ADHD儿童在时间维度上的视觉选择性注意的基本机制,揭示其表征搜索能力是否存在缺陷,研究采用RSVP范式,通过实验材料(字母和数字)和呈现方式操作两种搜索方式:序列搜索和平行搜索,比较ADHD儿童(18名)和控制组儿童(17名)的成绩差异。结果发现:①在平行搜索和序列搜索条件下,ADHD儿童的成绩均低于正常控制组;②比较平行搜索和序列搜索条件下的成绩变化,以及由低难度到高难度上成绩的变化,无论是正确率还是反应时均发现ADHD儿童和正常儿童具有相同的成绩变化模式。结论认为ADHD儿童在视觉选择性注意的基本搜索机制上并不存在明显缺陷。     

Restraint and Cancellation: Multiple Inhibition Deficits in Attention Deficit Hyperactivity Disorder

We used variations of the stop signal task to study two components of motor response inhibition—the ability to withhold a strong response tendency (restraint) and the ability to cancel an ongoing action (cancellation)—in children with a diagnosis of attention deficit hyperactivity disorder (ADHD) and in non-ADHD controls of similar age (ages 7–14 years). The goal was to determine if restraint and cancellation were related and if both were deficient in ADHD. The stop signal task involved a choice reaction time task (go task) which required a rapid response. The demand for inhibitory control was invoked through the presentation of a stop signal on a subset of go trials which required that the ongoing response be suspended. The stop signal was presented either concurrently with the go signal (restraint version) or after a variable delay (cancellation version). In Study 1, we compared ADHD and control children on the cancellation version of the stop task; in Study 2, we compared ADHD and controls on the restraint version. In Study 3, a subset of ADHD and control participants completed both tasks so that we could examine convergence of these dimensions of inhibition. Compared to control participants, ADHD participants showed a deficit both in the ability to cancel and to restrain a speeded motor response. Performance on the restraint version was significantly correlated with performance on the cancellation version in controls, but not in ADHD participants. We conclude that ADHD is associated with deficits in both restraint and cancellation subcomponents of inhibition.     

Children with Attention Deficit Hyperactivity Disorder

ABSTRACT

It is estimated that there have been over 4,000 articles in the literature on the subject of attentional problems, addressing its etiology, epidemiology, assessment, diagnosis, and treatment. This article reviews recent and relevant literature with an eye toward functional conclusions and linkages between assessment and intervention. The article concludes by providing a problem-solving model that integrates parent or teachers' referral concerns, reasons for these concerns, assessment methods, and intervention strategies. In the end, four definitive conclusions are drawn, and the importance of multimodal strategies that collaboratively involve home, school, and community settings is emphasized.