Attention deficit/hyperactivity disorders (ADHD) and autism spectrum disorders (ASD) frequently co-occur. However, we know little about the neural basis of the overlaps and distinctions between these disorders, particularly in young adulthood – a critical time window for brain plasticity across executive and socioemotional domains. Here, we systematically review 75 articles investigating ADHD and ASD in young adult samples (mean ages 16–26) using cognitive tasks, with neural activity concurrently measured via electroencephalography (EEG) – the most accessible neuroimaging technology. The majority of studies focused on event-related potentials (ERPs), with some beginning to capitalise on oscillatory approaches. Overlapping and specific profiles for ASD and ADHD were found mainly for four neurocognitive domains: attention processing, performance monitoring, face processing and sensory processing. No studies in this age group directly compared both disorders or considered dual diagnosis with both disorders. Moving forward, understanding of ADHD, ASD and their overlap in young adulthood would benefit from an increased focus on cross-disorder comparisons, using similar paradigms and in well-powered samples and longitudinal cohorts.

注意力缺陷/多动障碍 (ADHD) 和自闭症谱系障碍 (ASD) 经常同时发生。然而，我们对这些疾病之间重叠和区别的神经基础知之甚少，特别是在成年早期——执行和社会情感领域大脑可塑性的关键时间窗口。在这里，我们系统地回顾了 75 篇文章，使用认知任务研究年轻人样本（平均年龄 16-26 岁）的 ADHD 和 ASD，同时通过脑电图 (EEG)（最容易获得的神经影像技术）测量神经活动。大多数研究集中于事件相关电位（ERP），其中一些研究开始利用振荡方法。自闭症谱系障碍 (ASD) 和多动症 (ADHD) 的重叠和特定特征主要存在于四个神经认知领域：注意力处理、表现监控、面部处理和感觉处理。该年龄组中没有研究直接比较这两种疾病或考虑对这两种疾病进行双重诊断。展望未来，对多动症、自闭症谱系障碍及其在青年期的重叠的理解将受益于对跨疾病比较的更多关注，使用类似的范式并在强有力的样本和纵向队列中进行。