Centre for Brain and Cognitive Development, Department of Psychological Sciences, Birkbeck, University of London, London, UK.
Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
J Child Psychol Psychiatry. 2022 Sep;63(9):1057-1067. doi: 10.1111/jcpp.13563. Epub 2022 Feb 20.
Uncovering the neural mechanisms that underlie symptoms of attention deficit hyperactivity disorder (ADHD) requires studying brain development prior to the emergence of behavioural difficulties. One new approach to this is prospective studies of infants with an elevated likelihood of developing ADHD.
We used a prospective design to examine an oscillatory electroencephalography profile that has been widely studied in both children and adults with ADHD - the balance between lower and higher frequencies operationalised as the theta-beta ratio (TBR). In the present study, we examined TBR in 136 10-month-old infants (72 male and 64 female) with/without an elevated likelihood of developing ADHD and/or a comparison disorder (Autism Spectrum Disorder; ASD).
Infants with a first-degree relative with ADHD demonstrated lower TBR than infants without a first-degree relative with ADHD. Further, lower TBR at 10 months was positively associated with temperament dimensions conceptually related to ADHD at 2 years. TBR was not altered in infants with a family history of ASD.
This is the first demonstration that alterations in TBR are present prior to behavioural symptoms of ADHD. However, these alterations manifest differently than those sometimes observed in older children with an ADHD diagnosis. Importantly, altered TBR was not seen in infants at elevated likelihood of developing ASD, suggesting a degree of specificity to ADHD. Taken together, these findings demonstrate that there are brain changes associated with a family history of ADHD observable in the first year of life.
揭示注意力缺陷多动障碍（ADHD）症状背后的神经机制需要研究行为困难出现之前的大脑发育。一种新的方法是对有患 ADHD 高风险的婴儿进行前瞻性研究。
我们使用前瞻性设计来检查一种在 ADHD 儿童和成人中广泛研究的振荡脑电图特征 - 较低和较高频率之间的平衡，用θ-β比（TBR）来表示。在本研究中，我们检查了 136 名 10 个月大的婴儿（72 名男性和 64 名女性）的 TBR，这些婴儿中有/没有患 ADHD 和/或对照障碍（自闭症谱系障碍；ASD）的高风险。
有 ADHD 一级亲属的婴儿的 TBR 低于没有 ADHD 一级亲属的婴儿。此外，10 个月时的 TBR 与 2 岁时与 ADHD 概念上相关的气质维度呈正相关。有 ASD 家族史的婴儿的 TBR 没有改变。
这是第一个证明 TBR 的改变在 ADHD 的行为症状出现之前就存在的证据。然而，这些改变与有时在患有 ADHD 诊断的较大儿童中观察到的改变不同。重要的是，在有患 ASD 高风险的婴儿中没有观察到 TBR 的改变，这表明 ADHD 具有一定的特异性。综上所述，这些发现表明，在生命的第一年，与 ADHD 家族史相关的大脑变化是可以观察到的。
