探討多重任務相關之神經調控機制

Abstract

駕駛車輛是一種需要持續專注的複雜行為，只要稍不留意就可能造成嚴重的交通事故。分心駕駛時，不同的腦區會負責整合接收刺激、分析資訊、決策選擇、作出回應。過去的研究透過量測腦電波訊號，來了解大腦與分心駕駛之關係，本研究透過新穎的神經調節機制分析 (Independent modulator analysis) 將不同腦區中頻譜獨立出神經調節元，藉此深入探討大腦運作，了解在多重任務中伴隨不同類型的分心因素如何影響大腦調控著不同腦區的變化。在駕駛行為的分析中，可發現反應時間隨作業程度上升而增加。同時，聽覺對於行為表現的干擾程度大於視覺。神經調節機制分析顯示在駕駛分心時存在不同神經調節元調控控著不同腦區。神經調節元調控的腦區頻帶在不同狀態下有不同影響。特別是在當同時執行的任務越多時，枕葉腦區被調控較多頻帶以處理額外的分心干擾。在雙重事件下的聽覺干擾，前額葉則會被調控較多頻帶。本研究提供不同的觀點，嘗試探討大腦深層影響不同腦區同步活化現象的神經調節機制，並了解在分心駕駛的狀態下，專注力是如何被影響及分配資源。

Driving is a complex task that requires drivers to pay attention all the time to control the cars. It takes only one split second of distraction can result in an accident. Distracted driving is regarded as an integrated task requiring different regions of the brain receive sensory data, coordinate information, make decision, and synchronize movement responses. Previous studies investigated electroencephalographic (EEG) dynamics associated with distracted driving. In this study, we further applied a novel independent modulator analysis (IMA) method to temporally independent EEG components to understand how the human executive control system coordinates different brain regions to simultaneously perform multiple tasks with different distractors. The behavioral results showed that the reaction time (RT) in response to the traffic event increased while multitasking. Moreover, the RT was longer when the distractor was presented in an auditory form versus a visual form. IMA results showed that there are performance-related independent modulators coordinating different brain regions while distracted driving. The component spectral fluctuations affected by the modulators were distinct between single- and dual-tasks. Specifically, more modulatory weights should project to the occipital region to deal with extra distracted stimulus in dual-tasks conditions. Comparison of modulatory weights between auditory and visual distractors showed that more modulatory weights projected to the frontal region while processing auditory distractor. This study provide valuable insights into the temporal dynamics of attentional modulation during multitasking as well as understanding of the underlying brain mechanisms that mediates the synchronization across brain regions and governs allocations of attention in distracted driving.