巴金森氏病患者之神經心理功能研究: 探討認知功能、監控記憶、及社會認知功能之關係

Abstract

巴金森氏病是常見的神經退化性疾病之一，其病理特徵位於基底核，由於涉及基底核─額葉迴路，因此患者除了臨床動作症狀外，亦常見非動作障礙，如失智症或神經精神症狀。近年研究指出輕度認知功能障礙是失智症的前驅，巴金森氏病患者常見執行功能障礙，而病程中失智症的發生則與後側腦區相關之認知功能障礙有關。監控記憶指個體對自己記憶功能的覺察，病患若能正確覺察記憶功能下降，即能早期治療。此外，「心智理論」指個體對他人的想法或情緒的察覺與推論，其為社會認知功能中重要的部分。監控記憶與「心智理論」能力和額葉功能關係密切，推測巴金森氏病患者上述功能可能有缺損，再者，哪些因素影響著巴金森氏病患者之社會認知功能尚待探討與釐清。本研究包含兩大部分，透過四個系列性研究探討上述問題。第一部分進行三個研究瞭解巴金森氏病患者之神經認知、監控記憶、社會認知等功能。初步結果發現巴金森氏病患者常見執行與記憶功能之缺損，監控記憶與覺察環境人際互動之能力亦下降；第二部分則進一步探究疾病嚴重度與執行功能（如監控與抑制控制功能）影響病患者社會認知功能之機制。早期巴金森病患者神經認知功能與社會認知功能均有缺損。執行功能為主要的神經認知功能缺損面向，而社會認知功能與執行功能（如概念形成、心智彈性、策略提取、抑制困難）間有顯著相關，病患比一般老年人需要更多的心理能力來推論他人的想法與意圖。站在臨床的觀點，我們的研究結果能作為發展神經復健計畫之參考以提升巴金森病患者的神經認知與社會認知功能。

Parkinson’s disease (PD) is a common neurodegenerative disease and pathologically characterized by the loss of dopaminergic neurons in the basal ganglia. Because of the pathological involvement of the frontal-striatal circuits, patients with PD also have non-motor symptoms, such as dementia and neuropsychiatric symptoms. Recent studies have suggested that mild cognitive impairment (MCI) is a precursor of dementia. Executive dysfunction is the most common in PD while the posterior cortical dysfunction is associated with the later development of dementia. Metamemory refers to the individual’s awareness of his/her own memory ability, and properly perceived decline in memory function early could facilitate early detection and intervention. In addition, Theory of Mind (ToM) refers the ability to infer other people’s thoughts or emotions in social situations and is one crucial part of social cognition. Metamemory and ToM ability are closely related to the frontal lobe function, it can be hypothesized that the above-mentioned functions were impaired in PD patients. Furthermore, what factors affect social cognition in patients with PD is needed to investigate. This thesis consists of two sections, a series of four studies were performed to explore these issues systematically. The first section comprises three studies and findings showed that executive function was most vulnerable in patients with PD; moreover, monitor ability of memory and others’ thoughts in social situation were impaired. However, the factors affect social cognition of patients with PD has still been unclear. Hence, we further explore the role of the disease severity and executive function, such as monitoring and inhibitory control, played in social cognition. Patients with early stage PD evidenced both individual neurocognitive and social cognitive dysfunction. Executive dysfunction is the most common and there is a significant relationship between ToM and executive function (concept formation, mental flexibility, strategy retrieval, and disinhibion). These patients need more psychological ability than healthy individuals do to infer others’ thought and intention. From the clinical perspective, it appears that the present findings might contribute to the development of neurorehabilitation program to improve both neurocognitive functions in patients with PD.