多重系統退化症之認知功能缺損：使用腦電圖探討認知功能變化

Abstract

多重系統退化症 (MSA) 是一種罕見且致命的神經退化性疾病，影響患者的運動和認知功能表現。目前對於多重系統退化症多注重於運動功能障礙，但對其認知功能缺損之研究仍然有限。本研究旨在採用綜合方法研究 MSA 患者的認知變化。本研究使用簡易精神狀態檢查 (MMSE) 和蒙特利爾認知評估 (MoCA) 測驗用於觀察 MSA 患者相較於健康對照組在認知功能中的特定領域差異，並且進行了被動式腦波監測和主動高階認知功能事件相關電位 (ERP) 作業。被動式腦波監測包括靜習態腦電圖及聽覺穩定狀態反應(ASSR)。此外，主動高階認知功能作業包括視覺特異刺激 (VOP) 及空間次激反應相容性 (SSR) 作業。 MMSE 和 MoCA 測驗結果顯示 MSA 患者的得分顯著下降。靜習態腦電圖顯示 MSA 組的 α 波峰值（PAF） 頻率較低，可視為皮質興奮性較低，且所有電極均呈現同樣的趨勢。同時， MSA 患者在 ASSR 中的 40 Hz 事件相關頻譜震盪 (ERSP) 也較弱。在 VOP 作業中， MSA 患者相較於健康對照組在 P3 成分波的振幅明顯降低，表示認知功能中的注意力缺陷。而在 SSR 作業中，發現 MSA 患者的 N2pc 成分波振幅相較於健康對照組也有明顯降低，顯示 MSA 患者在空間選擇性處理方面存有缺陷。與對照組相比， MSA 患者在 MoCA 測驗中得分明顯在視覺空間、執行和注意力較低，並且 MoCA 測驗與 P3 成分波之間存有潛在的相關性。因此，本論文以監測腦電圖探討神經活動之研究可被視為神經退化性疾病的預測生物標記。此外，這些結果為 MSA 患者在認知功能缺損提供了重要的見解，未來的研究應該更加重視 MSA 中的認知功能並延伸到臨床診斷。

Multiple system atrophy (MSA) is a rare and fatal neurodegenerative disease (NDD) affecting both motor and cognitive functions in patients. While motor deficits have been extensively studied, understanding cognitive impairments in MSA remains limited. This study aimed to investigate cognitive changes in MSA patients using a comprehensive approach. In this study, the Mini-Mental Status Examination (MMSE) and Montreal Cognitive Assessment (MoCA) tests were used to observe specific domains in cognitive function. The passive EEG paradigms and active high-level event-related potentials (ERPs) tasks were conducted. Passive EEG paradigms included the resting-state EEG and auditory steady-state response (ASSR). Additionally, active high-level function tasks included visual oddball paradigm (VOP) and spatial stimulus-response (SSR) tasks. Results in MMSE and MoCA tests revealed significantly decreased scores in MSA patients. The resting-state EEG showed lower PAF in the MSA group, indicating lower cortical excitability with a consistent trend at all electrodes. Meanwhile, 40 Hz event-related spectral perturbation (ERSP) in the ASSR was also weaker in the MSA patients. The VOP task suggested attention deficits in MSA patients compared to healthy controls. The amplitudes of P3 components in the MSA group were significantly reduced, suggesting impairment of attention deficits in cognitive function. MSA patients had significantly decreased N2pc components, reflecting deficits in spatially selective processing. The MoCA test displayed notably lower scores in MSA compared to the control group, especially in visuospatial, executive, and attention domains. There was an approaching significant correlation between the MoCA test and P3 components. Thus, investigating neural activity using EEGs might be considered a predictive biomarker in neurodegenerative disease. Moreover, these results provide important insights into MSA patients who have cognitive impairments, and future studies should put more emphasis on cognitive functions in MSA and reach out to clinical diagnosis.