幽默的腦神經機制   免費試閱

The Neural Substrates of Humor Processing: An Integrative Review

幽默在人類的認知與情感歷程扮演重要角色。近年腦造影技術的提升，使得對幽默歷程的腦神經機制有更加的認識。本研究者提出「幽默三元論」，即「幽默認知、情感與笑模式」，乃指幽默理解、幽默欣賞和幽默反應。幽默理解主要在額葉和顳葉等區域，主宰失諧偵側和解困的歷程；幽默欣賞主要在中腦邊緣系統的酬賞中心，扮演愉悅情緒感受；笑的行為反應主要在輔助運動區。然而，上述過去研究大多使用「幽默」和「非幽默」的條件相比，該做法是無法區分幽默歷程中認知與情感成分。本研究在幽默和非幽默條件之外，分別再加入「花園路徑句」與「失諧未解困」為條件的設計，有效分離幽默歷程的神經迴路模式：「失諧」主要在右邊顳中回和額中回，扮演語意衝突的偵探及語意訊息的儲存。「解困」主要在左邊額下回、額上回和頂下葉，主宰語意理解與統整。「愉悅感受」主要在左邊腹內側前額葉皮質、雙邊杏仁核和海馬旁回，與酬賞回饋系統有關。幽默歷程之基礎研究，整合了認知、神經生物與行為的研究取向，亦可提供在語言、正向情緒與工作記憶的認知神經科學研究之共構證據。

Humor is an important cognitive and affective phenomenon. Remarkable advances in fMRI techniques have made it possible to study the neural mechanisms underlying humor processing. The present study proposes a “Tri-component Model of Humor Processing”, in which humor processing involves cognition (comprehension), affect (appreciation) and the physical response of laughter (behavior). Previous research has found that regions in the frontal and temporal lobes become active during the humor comprehension process, which involves the detection and resolution of incongruity. The mesocorticolimbic dopaminergic system, associated with the experience of amusement, is responsive during the humor appreciation process. Finally, the physical laughter response has been associated with activity in the supplementary motor area (SMA). Earlier research, however, mainly “funny” and “unfunny” conditions, making it impossible to distinguish between cognitive and affective aspects of humor processing. To address this issue, our two studies made use of a novel design that incorporated a “garden path sentence” condition and a “nonsensical” condition. Results from these studies led to the development of a three-stage model of the neural circuit of humor processing. In this three-stage model, the detection of semantic incongruities involves the right middle temporal gyrus (MTG) and right medial frontal gyrus (MFG); the resolution of incongruities involves the left inferior frontal gyrus (IFG), left superior frontal gyrus (SFG), and left inferior parietal lobule (IPL); and the emotional experience of mirth or amusement is associated with the left ventral medial prefrontal cortex (vmPFC), the bilateral amygdalae and the bilateral parahippocampal gyri. We argue that this model successfully integrates behavioural, cognitive and neurobiological approaches to humor and suggest that it has the potential to serve as a foundation for further research into the neural mechanisms underlying the cognitive and affective processing of humor. We further recommend this model for use in developing converging lines of cognitive neuroscience evidence in research into phenomena as diverse as language, positive emotions, and working memory.