健康與自閉症青少年之心智理論神經機制

Neural Correlates of Theory of Mind in Typically Developing Youths and Youths with Autism Spectrum Disorder

余季霖(Chi-Lin Yu)

指導教授 ： 周泰立

國立臺灣大學/理學院/心理學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201800929

摘要

心智理論(Theory of Mind, ToM)是社會互動中必備能力，使我們得以感受並 理解他人的心理狀態。過往腦造影研究發現兩大功能性神經系統支持心智理論之 運作，包含經驗感受系統(experience sharing system)及心智推論系統(mentalizing system)。而過去自閉症(autism spectrum disorder)研究中，發現患者之心智理論功 能有所缺損，並伴隨兩大系統的神經活動異常。然而，未有研究直接探討患者兩 大系統之間的連結(connectivity)是否異常。因此，本研究欲藉功能性磁振造影， 探討健康青少年與自閉症青少年之心智理論神經機制，與兩大系統間的連結。本 研究共有健康組與自閉症組青少年各 28 位，使其於掃描時進行心智理論作業。 作業中會出現兩個三角形，受試者需判斷兩者是否正進行互動，抑或隨機移動。 結果發現，共 14 個腦區涉入於健康組心智理論歷程，包含雙側梭狀迴(fusiform gyrus)、雙側顳中迴(middle temporal gyrus, MTG)、雙側顳頂交界區 (temporoparietal junction, TPJ)、雙側額下迴(inferior frontal gyrus, IFG)、雙側前運 動皮質(premotor)、楔前葉(precuneus)，及背側、中間、腹側之內側前額葉皮質 (dorsal, middle, and ventral medial prefrontal cortex)。結果亦顯示自閉症組較健康 組於 precuneus 有較高活化量，且自閉症組於經驗感受系統(premotor 及 IFG)與心 智推論系統(TPJ 及 MTG)間有較弱的連結。綜上所述，本研究認為自閉症青少年 與正常青少年之心智理論神經機制有所不同，且自閉症患者之心智理論缺損，主 要源於兩大系統間的連結異常。

關鍵字

心智理論 ； 自閉症 ； 功能性磁振造影 ； 功能性腦連結 ； 心智推論系統 ； 經驗感受系統

並列摘要

Theory of Mind (ToM), the ability to share and understand others’ mental states, is important in social situations. Previous studies have found two neural systems to support ToM processing, including the experience sharing system and the mentalizing system. Individuals with autism spectrum disorder (ASD) have been found to underlie deficits in ToM and aberrant neural activities in the experience sharing system and the mentalizing system, yet little is known about the connectivity patterns in these two systems. We investigated neural correlates underlying ToM in youths with ASD and typically developing (TD) youths by using functional magnetic resonance imaging (fMRI). The sample consisted of 28 TD youths and 28 youths with ASD. They were scanned while doing a ToM task that had animations of two triangles moving either intentionally or randomly. Participants had to judge if there was interaction between two triangles. Results demonstrated 14 brain regions supporting normal ToM processing in TD youths, including the bilateral fusiform, bilateral middle temporal gyrus (MTG), bilateral temporoparietal junction (TPJ), bilateral inferior frontal gyrus (IFG), bilateral premotor, precuneus, dorsal, middle, and ventral medial prefrontal cortex (DMPFC/MMPFC/VMPFC). Furthermore, as compared to TD youths, youths with ASD showed increased activation in the precuneus and weaker inter-connectivity between the experience sharing system (bilateral premotor & bilateral IFG) and the mentalizing system (bilateral TPJ & bilateral MTG). In summary, these findings implied different functional organizations of ToM processing between youths with ASD and TD youths, further suggesting that the disruption in neural circuitry between the experience sharing system and the mentalizing system could be an influential factor of ToM impairments in youths with ASD.

並列關鍵字

Theory-of-mind ； Autism spectrum disorder ； fMRI ； functional connectivity ； mentalizing ； experience sharing

參考文獻

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