新一期Brain雜志網(wǎng)絡(luò)版刊登了法國研究人員的最新論文"Mentalizing under influence: abnormal dependence on prior expectations in patients with schizophrenia",，科學家認為精神分裂癥患者不能正確辨別他人行為意圖的原因之一,，在于他們不能恰當運用已有經(jīng)驗和剛剛獲取的直觀信息。
電地鐵上,，如果一個人從座位上站起來,，他是想在下一站下車,，還是想給你讓座？正常人一般能很快辨別他人行為意圖,，這也是人們在社會生存的一項基本技能,，但精神分裂癥患者卻沒有這種能力。
人們判斷他人行為意圖的能力主要建立在兩種信息的基礎(chǔ)上：第一種是通過觀察他人動作獲取的直觀信息,；第二種來源于已有的知識和經(jīng)驗,。只有借助后者，人們才能理解感覺器官提供的零碎信息,。
法國研究人員對陰性和陽性兩種精神分裂癥患者進行實驗,，其中陰性癥狀表現(xiàn)為情感淡漠、主動性缺乏,，陽性癥狀表現(xiàn)為幻覺和妄想,。
首先,，實驗對象觀看一些視頻片段，在這些片段中,，演員們分別帶著不同的目的去操作一些物體,。為形成先驗印象，其中一些片段被多次播放,。然后,，實驗對象重新觀看經(jīng)過刪節(jié)的相同片段。研究人員通過這種方式控制實驗對象能獲取的直觀信息量,，然后讓他們猜測演員的意圖,。
實驗結(jié)果表明，陰性患者不會利用經(jīng)驗,，對他人的意圖完全沒有任何預(yù)期,；反之，陽性患者則會過分依賴經(jīng)驗,，以至于無視直觀信息,，他們的想法不會因感官感受到的信息而改變。
精神分裂癥患者的這種癥狀無法通過藥物治療,，新研究成果有助于人們探索新的認知療法,，幫助患者更好地運用經(jīng)驗來判斷他人的行為意圖。此外,，這一發(fā)現(xiàn)也可用來治療和陰性精神分裂癥類似的自閉癥,。（生物谷Bioon.com）
doi:10.1093/brain/awr306
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PMID:
Mentalizing under influence: abnormal dependence on prior expectations in patients with schizophrenia
Valerian Chambon1, Elisabeth Pacherie2,*, Guillaume Barbalat3,4,*, Pierre Jacquet1, Nicolas Franck1,4 and Chl?é Farrer5,6
An impaired ability to appreciate other people's mental states is a well-established and stable cognitive deficit in schizophrenia, which might explain some aspects of patients’ social dysfunction. Yet, despite a wealth of literature on this topic, the basic mechanisms underlying these impairments are still poorly understood, and their links with the clinical dimensions of schizophrenia remain unclear. The present study aimed to investigate the extent to which patients’ impaired ability to appreciate other people's intentions (known as mentalizing) may be accounted for by abnormal interaction between the two types of information that contribute to this ability: (i) the sensory evidence conveyed by movement kinematics; and (ii) the observer's prior expectations. We hypothesized that this is not a generalized impairment, but one confined to certain types of intentions. To test this assumption, we designed four tasks in which participants were required to infer either: (i) basic intentions (i.e. the simple goal of a motor act); (ii) superordinate intentions (i.e. the general goal of a sequence of motor acts); (iii) social basic; or (iv) social superordinate intentions (i.e. simple or general goals achieved within the context of a reciprocal interaction). In each of these tasks, both prior expectations and sensory information were manipulated. We found that patients correctly inferred non-social, basic intentions, but experienced difficulties when inferring non-social superordinate intentions and both basic and superordinate social intentions. These poor performances were associated with two abnormal patterns of interaction between prior expectations and sensory evidence. In the non-social superordinate condition, patients relied heavily on their prior expectations, while disregarding sensory evidence. This pattern of interaction predicted the severity of ‘positive’ symptoms. Social conditions prompted exactly the opposite pattern of interaction: patients exhibited weaker dependence on prior expectations while relying strongly on sensory evidence, and this predicted the severity of ‘negative’ symptoms. We suggest both these patterns can be accounted for by a disturbance in the Bayesian inferential mechanism that integrates sensory evidence (conveyed by movement kinematics) into prior beliefs (about others’ mental states and attitudes) to produce accurate inferences about other people's intentions. on.
