Ellis Alissa J, Kinzel Chantelle, Salgari Giulia C, Loo Sandra K
Semel Institute of Neuroscience and Human Behavior, Department of Psychiatry, University of California, Los Angeles, USA.
Semel Institute of Neuroscience and Human Behavior, Department of Psychiatry, University of California, Los Angeles, USA.
Neuropsychologia. 2017 Jul 28;102:45-51. doi: 10.1016/j.neuropsychologia.2017.06.003. Epub 2017 Jun 3.
Atypical asymmetry in brain activity has been implicated in the behavioral and attentional dysregulation observed in ADHD. Specifically, asymmetry in neural activity in the right versus left frontal regions has been linked to ADHD, as well as to symptoms often associated with ADHD such as heightened approach behaviors, impulsivity and difficulties with inhibition. Clarifying the role of frontal asymmetry in ADHD-like traits, such as disinhibition, may provide information on the neurophysiological processes underlying these behaviors.
ADHD youth (ADHD: n = 25) and healthy, typically developing controls (TD: n = 25) underwent an electroencephalography (EEG) recording while completing a go/no-go task-a commonly used test measuring behavioral inhibition. In addition, advanced signal processing for source localization estimated the location of signal generators underlying frontal alpha asymmetry (FA) during correct and incorrect trials.
This is the first study in ADHD to demonstrate that the dorsal-lateral prefrontal cortex (DLPFC) may be responsible for generating frontal alpha. During failed inhibition trials, ADHD youth displayed greater FA than TD youth. In addition, within the ADHD group, frontal asymmetry during later processing stages (i.e., 400-800ms after stimulus) predicted a higher number of commission errors throughout the task.
These results suggest that frontal alpha asymmetry may be a specific biomarker of cognitive disinhibition among youth with ADHD.
大脑活动中的非典型不对称与注意缺陷多动障碍（ADHD）中观察到的行为和注意力失调有关。具体而言，右侧与左侧额叶区域神经活动的不对称与ADHD以及通常与ADHD相关的症状有关，如增强的趋近行为、冲动性和抑制困难。阐明额叶不对称在类似ADHD的特质（如去抑制）中的作用，可能会提供有关这些行为背后神经生理过程的信息。
ADHD青少年（ADHD组：n = 25）和健康的、发育正常的对照组（TD组：n = 25）在完成一项停止信号任务（一种常用的测量行为抑制的测试）时进行了脑电图（EEG）记录。此外，用于源定位的先进信号处理估计了正确和错误试验期间额叶α不对称（FA）背后信号发生器的位置。
这是第一项关于ADHD的研究，表明背外侧前额叶皮层（DLPFC）可能负责产生额叶α波。在抑制失败的试验中，ADHD青少年比TD青少年表现出更大的FA。此外，在ADHD组中，后期处理阶段（即刺激后400 - 800毫秒）的额叶不对称预测了整个任务中更高的错误率。
这些结果表明，额叶α不对称可能是ADHD青少年认知去抑制的一种特定生物标志物。
