Department of Child and Adolescent Psychiatry, University of Heidelberg, Blumenstraße 8, D-69115 Heidelberg, Germany.
Behav Brain Funct. 2011 Aug 25;7:38. doi: 10.1186/1744-9081-7-38.
We aimed to investigate the influences of attention deficit/hyperactivity disorder (ADHD) on response evaluation, as reflected by the postimperative negative variation (PINV), a slow event-related potential.
We investigated PINV as an indicator of performance uncertainty in an audio-visual contingent negative variation (CNV) paradigm with an interstimulus interval of 3 seconds. A constant, unilateral, quick motor reaction with either the right or the left thumb was required after an auditory forewarned (S1) visual imperative stimulus (S2). We examined 18 ADHD patients (combined or hyperactive-impulsive subtype) aged between 8 and 14 years and an age-, sex and IQ-matched control group of 19 healthy subjects using 64-channel high-density EEG. A first run was recorded drug-free, a second one under methylphenidate (MPH) medication in the ADHD group.
We found a significantly increased negativity of the PINV-component over the ventrolateral prefrontal cortex in ADHD children compared to the healthy control group. PINV amplitude was influenced by movement side, most likely due to the slightly more difficult task when left hand responses were required. After the intake of MPH, PINV amplitudes of ADHD children normalized.
We conclude that children with ADHD are likely to be more uncertain about the correctness of their performance and interpret the increased PINV as a hint towards compensatory mechanisms for a deficit in the evaluation of contingencies. Further studies are needed to assess the exact extent to which remainders of eye-movement related potentials contribute to PINV amplitude despite the correction for eye-artifacts.
我们旨在研究注意缺陷多动障碍（ADHD）对反应评估的影响，这反映在滞后正变（PINV）上，即一种缓慢的事件相关电位。
我们在一个视听伴随负变（CNV）范式中，用 3 秒的刺激间隔，研究了 PINV 作为表现不确定性的指标。在听觉预告（S1）视觉命令刺激（S2）后，要求被试用右手或左手拇指进行快速、单侧的恒定运动反应。我们用 64 通道高密度脑电图检查了 18 名 8 至 14 岁的 ADHD 患者（合并或多动冲动亚型）和 19 名年龄、性别和智商匹配的健康对照组。第一组无药物记录，第二组在 ADHD 组中使用哌醋甲酯（MPH）药物记录。
我们发现，与健康对照组相比，ADHD 儿童的额下外侧前额叶皮层的 PINV 成分明显更负。PINV 幅度受到运动侧的影响，这很可能是由于当需要左手反应时任务稍微更难。在服用 MPH 后，ADHD 儿童的 PINV 幅度恢复正常。
我们得出结论，ADHD 儿童可能对自己的表现正确性更不确定，并将增加的 PINV 解释为对意外事件评估缺陷的补偿机制的暗示。需要进一步的研究来评估眼球运动相关电位的残余物在多大程度上尽管纠正了眼球运动伪迹，但对 PINV 幅度仍有贡献。
