Bresnahan Susan M, Barry Robert J
Department of Psychology, Brain and Behaviour Research Institute, University of Wollongong, NSW 2522, Australia.
Psychiatry Res. 2002 Oct 10;112(2):133-44. doi: 10.1016/s0165-1781(02)00190-7.
Attention deficit hyperactivity disorder (ADHD) in children and adolescents is characterised by excessive restlessness and an extremely poor concentration span, resulting in impulsive and disruptive behaviour. Clinical observation of ADHD in adults suggests that the early hyperactivity is diminished in terms of its impact on social and academic function, while impulsive-type behaviours remain unchanged. EEG studies in children and adolescents with ADHD have reported significantly more low-frequency power (predominantly theta) and less high-frequency power (predominantly beta) than in normal subjects. In normal children and adolescents, a decrease in theta power and an increase in beta power are found with increasing age, leading some researchers to interpret the EEG anomalies in ADHD as evidence of developmental delay. Studies of adults with ADHD compared with normal adult control subjects have found a reduction in the difference between the two groups, suggesting that the reduced beta activity apparent in ADHD children and adolescents changes with age. Adults with ADHD thus appear to have elevated low-frequency power as their predominant EEG difference from normal control subjects. The present study examined whether this EEG profile was specific to adult ADHD patients. Quantitative EEGs were recorded at rest in an eyes-open condition and used to compare 50 adult patients diagnosed with ADHD with 50 non-ADHD subjects (who presented for ADHD assessment but failed to meet the diagnostic criteria) and 50 control subjects. The ADHD group differed from both the non-ADHD and the control groups on the basis of elevated theta activity. The ADHD and control groups did not differ in beta activity, but relative theta was reduced and relative beta power was elevated in the non-ADHD group compared with both the ADHD and control groups. These results suggest that quantitative EEG may be used to differentiate ADHD adults from both normal adults and adults who display some of the symptoms of ADHD, but fail to meet the diagnostic criteria of ADHD.
儿童和青少年注意力缺陷多动障碍（ADHD）的特征是过度烦躁不安和注意力极度不集中，导致冲动和破坏性行为。对成人ADHD的临床观察表明，早期多动对社交和学业功能的影响有所减轻，而冲动型行为则保持不变。对患有ADHD的儿童和青少年进行的脑电图研究报告称，与正常受试者相比，低频功率（主要是θ波）显著增加，高频功率（主要是β波）显著减少。在正常儿童和青少年中，随着年龄增长，θ波功率降低，β波功率增加，这使得一些研究人员将ADHD中的脑电图异常解释为发育延迟的证据。与正常成人对照组相比，对患有ADHD的成人进行的研究发现两组之间的差异有所减小，这表明ADHD儿童和青少年中明显降低的β波活动会随着年龄而变化。因此，患有ADHD的成年人似乎以低频功率升高为其与正常对照受试者脑电图的主要差异。本研究调查了这种脑电图特征是否为成人ADHD患者所特有。在睁眼休息状态下记录定量脑电图，用于比较50名被诊断患有ADHD的成年患者、50名非ADHD受试者（因ADHD评估前来就诊但未达到诊断标准）和50名对照受试者。ADHD组因θ波活动升高而与非ADHD组和对照组均存在差异。ADHD组和对照组在β波活动方面没有差异，但与ADHD组和对照组相比，非ADHD组的相对θ波降低，相对β波功率升高。这些结果表明，定量脑电图可用于区分患有ADHD的成年人与正常成年人以及表现出一些ADHD症状但未达到ADHD诊断标准的成年人。
