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

选择性注意力是一种重要的认知功能，它允许人们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预测刺激出现的位置时，在该位置处的刺激的处理将被增强，而在潜在干扰物可能出现的无人值守位置处的处理将被抑制。在具有典型发育的成年人中，顶枕叶皮质上的α带振荡活动（8-15 Hz）的偏侧增加已被公认为使用高密度脑电图（EEG）进行注意力控制的指标。在自闭症谱系障碍（ASD）患者中，异常的α振荡动力学表明，参与注意力控制的大脑区域被激活。此外，ASD患者在分散注意力方面存在有据可查的行为障碍。这些人还表现出参与注意力控制的额顶叶区域的非典型激活，并可能减少注意力网络中关键区域之间的连接。然而，ASD注意力控制的神经生理缺陷尚未明确确定，注意力控制的神经网络可能是完整的，但潜在的奖励回路的非典型激活有助于ASD个体的注意力控制缺陷。 这项工作的目标是描述ASD注意控制的神经生理学特征，并研究动机在调节这些过程中的作用。 属于受限或限定兴趣（RCI，例如火车）的刺激通常比社交刺激更能激励ASD患者，并且已显示增加的动机可增强ASD中注意力控制区域的激活。这可能是注意控制回路对社会和非社会线索的非典型激活可以在ASD个体中调节 通过呈现与这些线索相关的激励性RCI刺激。 这项工作的指导模型认为，出生时的初始神经病理学降低了对社会奖励的敏感性，导致注意力控制脑区的非典型激活，这是通过对社会刺激的注意力受损和对RCI刺激的注意力增加而传播的。在拟议的工作中，用于预期注意力控制的α波段脑电指数将与RCI的标准临床ASD严重程度测量相关。这将是至关重要的，了解注意力控制缺陷和RCI在ASD之间的关系。一个视觉空间提示范例将与上述的α-波段脑电图指标结合使用，以检查注意力控制的完整性。动机显着性的命令性刺激将被操纵，通过呈现参与者特定的RCI刺激，预期注意控制将在非社会和社会领域进行检查。这些研究的结果将与早期干预有关，以调节ASD注意力控制缺陷的非典型神经激活，并改善成年后的整体社会功能。

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.