Abstract:
Schizophrenia is marked by aberrant processing of complex speech and gesture, which may contribute functionally to its impaired social communication. To date, extant neuroscientific studies of schizophrenia have largely investigated dysfunctional speech and gesture in isolation, and no prior research has examined how the two communicative channels may interact in more natural contexts. Here, we tested if patients with schizophrenia show aberrant neural processing of semantically complex story segments, and if speech-associated gestures (co-speech gestures) might modulate this effect. In a functional MRI study, we presented to 34 participants (16 patients and 18 matched-controls) an ecologically-valid retelling of a continuous story, performed via speech and spontaneous gestures. We split the entire story into ten-word segments, and measured the semantic complexity for each segment with idea density, a linguistic measure that is commonly used clinically to evaluate aberrant language dysfunction at the semantic level. Per segment, the presence of numbers of gestures varied (n = 0, 1, +2). Our results suggest that, in comparison to controls, patients showed reduced activation for more complex segments in the bilateral middle frontal and inferior parietal regions. Importantly, this neural aberrance was normalized in segments presented with gestures. Thus, for the first time with a naturalistic multimodal stimulation paradigm, we show that gestures reduced group differences when processing a natural story, probably by facilitating the processing of semantically complex segments of the story in schizophrenia.
摘要:
精神分裂症的特点是复杂的言语和手势的异常处理,这可能在功能上导致其社交障碍。迄今为止,现存的精神分裂症神经科学研究主要是孤立地研究言语和手势功能失调,以前没有研究过这两种交流渠道在更自然的环境中如何相互作用。这里,我们测试了精神分裂症患者是否表现出语义上复杂的故事片段的异常神经处理,以及语音关联手势(协同语音手势)是否可以调节这种效果。在一项功能磁共振成像研究中,我们向34名参与者(16名患者和18名匹配对照)展示了一个连续故事的生态有效复述,通过语音和自发手势执行。我们把整个故事分成十个字的片段,并用思想密度测量每个片段的语义复杂性,临床上通常用于在语义水平上评估异常语言功能障碍的语言度量。每个细分市场,手势数量的存在不同(n=0,1,+2)。我们的研究结果表明,与控件相比,患者在双侧中额叶和下顶叶区域的更复杂节段的激活减少.重要的是,这种神经异常在手势显示的片段中被归一化。因此,第一次使用自然主义的多模态刺激范式,我们展示了手势在处理自然故事时减少了群体差异,可能是通过促进精神分裂症故事的语义复杂部分的处理。