奖惩对注意缺陷多动障儿童情感决策的影响

采用简化版儿童赌博任务,其中操纵了奖励和惩罚的强度,探察两种亚型(注意缺陷型和混合型)ADHD儿童的情感决策能力,同时采集儿童在任务中的皮肤电活动以探析ADHD儿童在情感决策中的生理机制.结果发现,在不同的奖惩强度下,ADHD儿童情感决策模式不同,在即刻奖励条件下,ADHD儿童情感决策的能力明显弱于正常对照组儿童,倾向于不利选择,所产生的预测性皮电振幅也明显低于正常对照组;在即刻惩罚条件下,ADHD儿童的情感决策能力未见异常.两种亚型ADHD儿童的表现模式相似.上述结果证明,ADHD儿童仅存在对奖励的异常敏感性,并确实影响了其决策能力,而其回避惩罚的能力正常.两种亚型ADHD儿童存在的问题相似.     

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。     

激活水平对两亚型ADHD儿童反应执行与抑制能力的影响

研究选取了混合型ADHD儿童14名,注意缺陷型ADHD儿童16名以及正常儿童18名,考察了在不同激活水平下,两亚型ADHD儿童之间,及其与正常儿童之间的反应执行能力与抑制能力的异同。采用传统的go/no-go任务,并将刺激间的时间间隔设置为1秒、4秒、8秒三种条件,分别对应高、中、低三种激活水平。结果发现,(1)与正常儿童相比,ADHD儿童的反应执行能力更容易受到激活水平的影响,且两亚型ADHD儿童受到的影响模式基本一致。具体而言:在高激活水平下,ADHD儿童与正常儿童差异最小;在中、低激活水平下,ADHD儿童与正常儿童差异增大,表明ADHD儿童状态调节能力落后。(2)两亚型ADHD儿童的功能缺损模式不同,混合型儿童在状态调节和反应抑制两方面都存在缺损,且其反应抑制缺陷不受激活水平影响;注意缺陷型儿童仅在状态调节方面受损。     

注意缺陷多动障碍儿童在不同加工阶段的干扰控制

采用刺激－刺激和刺激－反应相容性任务范式,将信息加工在知觉和反应阶段的冲突效应分离开来,考察注意缺陷多动障碍（Attention Deficit Hyperactivity Disorder,简称ADHD）儿童在知觉和反应阶段冲突控制的模式和时间轨迹。结果发现,在反应阶段,ADHD儿童的干扰控制能力明显弱于正常对照组儿童,混合型ADHD儿童的能力更弱于注意缺陷型ADHD儿童;在知觉阶段,ADHD儿童没有明显的干扰抑制缺损,两组ADHD儿童（注意缺陷型和混合型）的表现模式相似;儿童抑制冲突干扰所遵循的时间轨迹在知觉和反应阶段有所不同：与知觉阶段相比,反应阶段需要更长的时间才能抑制冲突干扰。但ADHD儿童和正常儿童之间的表现模式相似     

两种亚型ADHD儿童的促进和抑制加工

采用图片Stroop任务,对两种亚型ADHD儿童的促进和抑制加工进行了研究。结果发现,不论在反应时还是错误率上,ADHD儿童和正常儿童在促进效应上的表现模式相似,但ADHD儿童在错误率上比正常儿童表现出更大的抑制效应,混合型ADHD儿童的抑制效应更大于注意缺陷型儿童。由于ADHD儿童仅选择性地在抑制加工上受损,而促进加工正常,这一结果提示,促进和抑制可能是具有不同机制的、分离的加工过程。     

奖惩线索对停止信号任务中抑制能力和心率、皮肤电的影响

采用不同类型强化刺激(中性刺激,奖励刺激,惩罚刺激,以及奖励、惩罚刺激并存)来改变可获得奖励和惩罚的强度和频度,分别考察不同类型强化条件对停止信号任务中抑制能力、心率和皮肤电的影响.结果显示:与奖惩混合条件相比,在奖励条件下,被试的反应速度快,但正确抑制率明显低于惩罚条件和奖惩混合条件;在奖励条件下,被试在任务完成过程中的心率明显高于反馈条件、惩罚条件和奖惩混合条件.四种条件下被试的皮肤电活动无差异.     

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。     

不同亚型ADHD儿童的视通道时距估计能力

本研究选取ADHD混合型儿童11名,ADHD注意缺损型儿童13名以及正常儿童15名,通过"平均估计长度"、"平均估计误差百分比"、"估计变异值"三个指标,考察不同亚型ADHD儿童在时距复制和言语估计上的稳定性和精确性。研究发现,在视觉刺激条件下,ADHD儿童的时距估计缺损并不受时距长度的影响;ADHD混合型儿童在多项任务中所表现的稳定性和精确性都差,而ADHD缺损型儿童只是稳定性差,说明ADHD混合型是ADHD中更严重的亚类型;ADHD儿童在时距估计任务中稳定性差,反映了其状态调节能力的落后。     

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。     

视觉选择性注意对注意缺损多动障碍儿童数字距离效应的影响

采用Posner的内源性和外源性线索实验范式,材料为1~9的阿拉伯数字(不包括5),以判断目标数字是否大于5为任务,考察视觉选择性注意中的内源性注意和外源性注意对注意缺陷型多动障碍儿童(ADHD)数字加工距离效应的影响。结果发现:(1)内源性和外源性注意条件下,正常儿童在数字判断加工任务中的反应时短于ADHD儿童;(2)内源性有效线索提示条件下,ADHD儿童和正常儿童均表现出显著的数字距离效应;而无效线索提示条件下,ADHD儿童的大小数字距离效应均不明显,正常儿童仍然表现出显著的数字距离效应;(3)外源性有效线索提示条件下,ADHD儿童的小数字距离效应显著,但大数字距离效应不明显,正常儿童则表现出显著的大小数字距离效应;而无效线索提示条件下,只有正常儿童表现出显著的数字距离效应,ADHD儿童的数字距离效应不显著。     

Development of "hot" executive function: the children's gambling task

Development of affective decision-making was studied in 48 children at two ages (3 and 4 years) using a simplified version of the Iowa Gambling Task (). On each of 50 trials, children chose from 1 of 2 decks of cards that, when turned, displayed happy and sad faces, corresponding to rewards (candies) won and lost, respectively. Cards in 1 deck offered more rewards per trial, but were disadvantageous across trials due to occasional large losses; cards in the other deck offered fewer rewards per trial, but were advantageous overall. On later trials, 4-year-olds made more advantageous choices than 3-year-olds, and 4-year-olds made more advantageous choices than would be expected by chance, whereas 3-year-olds made more disadvantageous choices than would be expected by chance. These findings, which were especially pronounced for girls, indicate that affective decision-making develops rapidly during the preschool period, possibly reflecting the growth of neural systems involving orbitofrontal cortex.     

Lack of Inhibition: A Motivational Deficit in Children With Attention Deficit/Hyperactivity Disorder and Children With Traumatic Brain Injury*

Recent research has demonstrated that both brain-injured children and children with attention deficit/hyperactivity disorder (ADHD) suffer from response inhibition deficits. To investigate whether these deficits can be influenced by motivational factors, the stop-signal task was performed with and without reward contingencies for successful inhibition. Three groups of children between 8 and 12 years of age, participated in the study: 31 children with ADHD, 37 with traumatic brain injuries (TBI), and 26 normal controls. Results indicated that, although all groups showed comparable learning effects, reward contingencies had different effects on the groups. Whereas the performance of children with ADHD under reward contingencies were brought up to the performance level of normal controls, rewards were found less effective at improving response inhibition in children with TBI. The results further support a motivational/energetic explanation of the inhibitory deficit in children with ADHD, and of a primary response inhibition deficit due to structural brain damage in children with TBI.     

Lack of inhibition: a motivational deficit in children with attention deficit/hyperactivity disorder and children with traumatic brain injury.

Recent research has demonstrated that both brain-injured children and children with attention deficit/hyperactivity disorder (ADHD) suffer from response inhibition deficits. To investigate whether these deficits can be influenced by motivational factors, the stop-signal task was performed with and without reward contingencies for successful inhibition. Three groups of children between 8 and 12 years of age, participated in the study: 31 children with ADHD, 37 with traumatic brain injuries (TBI), and 26 normal controls. Results indicated that, although all groups showed comparable learning effects, reward contingencies had different effects on the groups. Whereas the performance of children with ADHD under reward contingencies were brought up to the performance level of normal controls, rewards were found less effective at improving response inhibition in children with TBI. The results further support a motivational/energetic explanation of the inhibitory deficit in children with ADHD, and of a primary response inhibition deficit due to structural brain damage in children with TBI.     

Covert detection of attractiveness among the neurologically intact: evidence from skin-conductance responses

Several studies have shown that participants, without a deficit in face recognition, give an increased skin conductance response (SCR) to familiar faces when presented subliminally, hence suggesting covert recognition of these faces. In the experiment presented here we manipulated familiarity and attractiveness and tested whether participants distinguished between faces for these variables when presented too fast to allow conscious recognition. Three sets of faces were presented: famous attractive; unfamiliar attractive; and unfamiliar less attractive. SCRs were the same for each category of faces whether presented subliminally or supraliminally, and were the same for attractive faces, whether famous or unfamiliar; however, SCRs differed between the attractive and less attractive faces. The findings support those of Stone et al (2001 Cognitive, Affective and Behavioral Neuroscience 1 183-191) and suggest that higher SCRs to famous faces are not necessarily due to covert recognition, but may be a response to the positive affective valence of the stimuli.     

海洛因戒除者的行为冲动性： 基于DDT和IGT任务反应模式的探讨

以61名男性海洛因戒除者和32名正常成年男性为被试,探讨了海洛因戒除者在延迟折扣任务和Iowa赌博任务两种决策条件下的冲动性反应模式及其关系。结果发现,海洛因戒除者的决策行为受其对即时强化的超敏感性或“即时收益优先”模式控制,其高冲动性特质既表现为对强化物长远价值的非敏感性,又表现为对强化物潜在风险的耐受性;该类人群上述两方面的特征虽有一定关联,但二者分别反应了其行为冲动性的两个相对独立的维度,且具有跨戒除时相的相对稳定性     

运用赌博任务测查不同攻击/受欺类别儿童的情感决策过程

攻击行为认知研究存在的一个重要问题是忽视情感对儿童认知加工的影响。考虑了情绪－认知整合过程的儿童行为决策更能全面而真实地反映社会信息加工情境下的攻击/受欺行为卷入过程。情感决策的赌博任务范式被认为能诱发类似于个人真实生活决策的表现,本研究运用计算机程序编制的标准赌博任务,以过程的视角考察了不同攻击/受欺儿童的情感决策特点。结果发现,不同类型儿童的有利-不利选择净分数、对有利-不利选择及奖惩频数的决策偏向存在显著差异。研究结果反映未卷入儿童在赌博任务上的整体表现优于其他类型儿童,攻击-受欺儿童仅次于未卷入儿童;直接攻击、攻击-受欺、未卷入儿童呈现惩罚定向的决策风格,但这三类儿童也表现出截然不同的趋势。     

Underlying processes in the poor response inhibition of children with Attention-Deficit/Hyperactivity Disorder

This study evaluated the effects of reward, punishment, and reward + punishment on the impulsive responses of ADHD children. The impulsive responses of ADHD and normal control boys (30 per group) were compared during performance of a go/no-go task, administered under reward-only, punishment-only, and reward + punishment conditions. When differences in aggression, anxiety, and IQ between these groups were controlled for, results indicated that the impulsivity levels of the ADHD group were higher than the control group in all three reinforcement conditions. Also, the ADHD group was more impulsive in the reward + punishment condition, compared to the reward-only and punishment-only conditions, and there was no difference between the reward-only and punishment-only conditions. The control groups showed no difference across the three reinforcement conditions. These findings raise the possibility that the poor response inhibition of ADHD children may be related to both a generalized inhibitory deficit and a response modulation deficit.     

Hot and Cool Aspects of Cognitive Control in Children with ADHD: Decision-Making and Inhibition

This study investigated hot and cool aspects of cognitive control in children with Attention Deficit Hyperactivity Disorder (ADHD). The study aimed to: (1) replicate the postulated response inhibition deficit of children with ADHD; (2) explore whether children with ADHD choose disadvantageously in a decision-making task and to explore the mechanisms underlying the expected response pattern; and (3) study whether performance on a combination of hot and cool executive control measures has predictive value for an ADHD diagnosis. The sample consisted of 20 children with ADHD and 22 normal developing children (NC, 8 to 12 years) matched on age, FSIQ, and gender. Two paradigms have been applied: (1) the stop signal paradigm, and (2) the adapted children's version of the IOWA Gambling task. There were no group differences for both paradigms. Both groups chose in a reward-oriented manner and seemed to develop the ability to take future consequences into account in making decisions. Moreover, feedback resulted in direct behavioral changes. Children with ADHD did not have a specific response inhibition deficit or a decision-making deficit.     

Temporal discounting of monetary rewards in children and adolescents with ADHD and autism spectrum disorders

It has been difficult to differentiate attention‐deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in terms of some aspects of their cognitive profile. While both show deficits in executive functions, it has been suggested that they may differ in their response to monetary reward. For instance, children with ADHD prefer small immediate over large delayed rewards more than typically developing controls. One explanation for this is that they discount the value of rewards to a higher degree as they are moved into the future. The current study investigated whether children with ADHD can be differentiated from those with ASD in terms of reward discounting. Thirty‐nine children (8–16 y) with ADHD, 34 children with ASD and 46 typically developing controls performed a hypothetical monetary temporal discounting task. Participants were instructed to make repeated choices between small variable rewards (0, 5, 10, 20, 30€) delivered immediately and large rewards delivered after a variable delay. Children with ADHD but not ASD discounted future rewards at a higher rate than typically developing controls. These data confirm steeper discounting of future rewards in ADHD and add to a small but growing literature showing that the psychological profile of ADHD can be distinguished from that of ASD in terms of disrupted motivational processes.