ABSTRACT

Objective: Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent and impairing neurodevelopmental disorder. While early childhood is a crucial time for early intervention, it is characterized by instability of ADHD diagnosis. Neural correlates of ADHD have potential to improve diagnostic accuracy; however, minimal research has focused on early childhood. Research indicates that disrupted neural connectivity is associated with ADHD in older children. Here, we explore network connectivity as a potential neural correlate of ADHD diagnosis in early childhood.

Method: We collected EEG data in 52 medication-naïve children with ADHD and in 77 typically developing controls (3–7 years). Data was collected with the EGI 128 HydroCel Sensor Net System, but to optimize the ICA, the data was down sampled to the 10-10 system. Connectivity was measured as the synchronization of the time series of each pair of electrodes. Subsequent analyses utilized graph theoretical methods to further characterize network connectivity.

Results: Increased global efficiency, which measures the efficiency of information transfer across the entire brain, was associated with increased inattentive symptom severity. Further, this association was robust to controls for age, IQ, SES, and internalizing psychopathology.

Conclusions: Overall, our findings indicate that increased global efficiency, which suggests a hyper-connected neural network, is associated with elevated ADHD symptom severity. These findings extend previous work reporting disruption of neural network connectivity in older children with ADHD into early childhood.

 抽象的

目的：注意力缺陷/多动障碍（ADHD）是一种非常普遍且损害神经发育的障碍。虽然幼儿期是早期干预的关键时期，但其特点是多动症诊断的不稳定。 ADHD 的神经相关因素有可能提高诊断准确性；然而，针对幼儿期的研究却很少。研究表明，神经连接中断与年龄较大的儿童多动症有关。在这里，我们探索网络连接作为儿童早期多动症诊断的潜在神经关联。

方法：我们收集了 52 名未接受药物治疗的 ADHD 儿童和 77 名正常发育对照（3-7 岁）的脑电图数据。数据是使用 EGI 128 HydroCel 传感器网络系统收集的，但为了优化 ICA，数据被下采样到 10-10 系统。连接性是通过每对电极的时间序列的同步来测量的。随后的分析利用图论方法进一步表征网络连接性。

结果：整体效率的提高（衡量整个大脑信息传输的效率）与注意力不集中症状严重程度的增加相关。此外，这种关联对于年龄、智商、社会经济地位和内化精神病理学的控制是强有力的。

结论：总的来说，我们的研究结果表明，整体效率的提高（这表明神经网络的高度连接）与 ADHD 症状严重程度的升高相关。这些发现将之前报告患有多动症的大龄儿童神经网络连接中断的研究延伸到了幼儿期。