The Neural Bases of Top-Down Attentional Control in Autism Spectrum Disorders

描述（由申请人提供）：选择性注意是一种重要的认知功能，它允许一个人在复杂的环境中专注于相关信息。当注意力被隐蔽地引导到一个预计会出现刺激的位置时，对该位置的刺激的处理将得到加强，而对可能出现潜在干扰的无人注意位置的处理将受到抑制。在发育典型的成年人中，经高密度脑电图（EEG）证实，顶枕皮质α波段振荡活动（8-15 Hz）的偏侧增加已被作为注意力控制的指标。在自闭症谱系障碍（ASD）患者中，异常的α振荡动力学表明与注意力控制有关的大脑区域被非典型地激活。此外，有充分证据表明，患有自闭症谱系障碍的人在分散注意力方面存在行为障碍。这些个体在涉及注意力控制的额顶叶区域也表现出非典型的激活，并且注意网络中关键区域之间的连接可能减少。然而，ASD中注意控制的神经生理缺陷尚未明确确立，并且有可能注意控制的神经网络是完整的，但是潜在奖励回路的非典型激活导致了ASD个体的注意控制缺陷。这项工作的目的是表征ASD的注意控制的神经生理学，并探讨动机在调节这些过程中的作用。

DESCRIPTION (provided by applicant): Selective attention is a crucial cognitive function that allows one to focus on relevant information in a complex environment. When attention is covertly directed to a location where a stimulus is predicted to appear, processing of stimuli at that location will be enhanced, whereas processing at unattended locations where potential distractors may appear will be suppressed. In adults with typical development, lateralized increases in alpha-band oscillatory activity (8-15 Hz) over parieto-occipital cortices have been well-established as a metric for attentional control using high-density electroencephalography (EEG). In individuals with autism spectrum disorders (ASD), aberrant alpha oscillatory dynamics suggest that brain regions involved in attentional control are atypically activated. Additionally, individuals with ASD have well-documented behavioral impairments in disengaging the focus of attention. These individuals have also shown atypical activations in frontoparietal regions involved in attentional control, and potentially reduced connectivity between key regions in the attentional network. Yet, the neurophysiological deficits in attentional control in ASD have not been clearly established, and it is possible that the neural networks for attentional control are intact, but atypical activations of underlying reward circuitry contribute to attention control deficits in individuals with ASD. The goal of this work is to characterize the neurophysiology of attentional control in ASD and to investigate the role of motivation in regulating these processes. Stimuli that fall within restricted or circumscribed interests (RCI, e.g. trains) are often more motivating to individuals with ASD than social stimuli, and increased motivation has been shown to enhance activation in attention control regions in ASD. It may be that the atypical activation o attentional control circuits to social and non-social cues can be regulated in individuals with ASD through the presentation of motivating RCI stimuli that are contingent on these cues. The guiding model for this work holds that initial neuropathology at birth reduces sensitivity to socia reward, resulting in atypical activation of attention control brain areas, which is propagated by impaired attention to social stimuli and increased attention to stimuli of RCI. In the proposed work, alpha-band EEG indices for anticipatory attentional control will be correlated with standard clinical ASD severity measures for RCI. This will be crucial for understanding the relationship between attentional control deficits and RCI in ASD. A visuospatial cueing paradigm will be used in conjunction with the aforementioned alpha-band EEG metric to examine the integrity of attentional control. Motivational salience of imperative stimuli will be manipulated through presentation of participant-specific RCI stimuli, and anticipatory attentional control will be examined in nonsocial and social domains. The findings of these studies will have relevance for early interventions to regulate atypical neural activations underlying attentional control deficitsin ASD, and improve overall social functioning into adulthood. PUBLIC HEALTH RELEVANCE: Selective attention or the ability to focus on relevant information in the environment and suppress irrelevant information is a crucial function for good mental health. There is evidence that atypical selective attention patterns underlie social functioning deficits in autism spectrum disorders (ASD), but the associated brain processes are unclear. This project will investigate the neurophysiological bases for selective attention deficit in ASD, and provide a fundamental understanding so that evidence-based interventions can be devised.