Abstract:
Variation in facial emotion processing abilities may contribute to variability in penetrance for psychotic symptoms in 22q11.2DS. However, the precise nature of the social cognitive dysfunction (i.e., facial expression perception vs. emotion recognition), the potential additional roles of genetic and environmental variabilities, and consequently the possibility of using this neurocognitive marker in clinical monitoring remain unclear. The present case study aimed at testing the hypothesis that when confounding factors are controlled, the presence of psychotic symptoms in 22q11.2DS is associated, at the individual level, with a neural marker of facial expression perception rather than explicit emotional face recognition. Two monozygotic twins with 22q11.2DS discordant for psychiatric manifestations performed (1) a classical facial emotion labelling task and (2) an implicit neural measurement of facial expression perception using a frequency-tagging approach in electroencephalography (EEG). Analysis of the periodic brain response elicited by a change of facial expression from neutrality indicated that the twin with psychotic symptoms did not detect emotion among neutral faces while the twin without the symptoms did. In contrast, both encountered difficulties labelling facial emotion. The results from this exploratory twin study support the idea that impaired facial expression perception rather than explicit recognition of the emotion expressed might be a neurocognitive endophenotype of psychotic symptoms that could be reliable at a clinical level. Although confirmatory studies should be required, it facilitates further discussion on the etiology of the clinical phenotype in 22q11.2DS.
摘要:
22q11.2DS中面部情绪处理能力的变化可能导致精神病症状的外显率变化。然而,社会认知功能障碍的确切性质(即,面部表情知觉vs.情感识别),遗传和环境变化的潜在额外作用,因此,在临床监测中使用这种神经认知标志物的可能性仍不清楚。本案例研究旨在检验以下假设:当混杂因素得到控制时,22q11.2DS中精神病症状的存在是相关的,在个人层面,具有面部表情感知的神经标记,而不是明确的情感面部识别。两个具有22q11.2DS精神表现不一致的单卵双胞胎进行了(1)经典的面部情绪标记任务和(2)在脑电图(EEG)中使用频率标记方法对面部表情感知进行隐式神经测量。对面部表情从中性变化引起的周期性大脑反应的分析表明,有精神病症状的双胞胎没有在中性面孔中检测到情绪,而没有症状的双胞胎则检测到。相比之下,两人都遇到了标记面部情绪的困难。这项探索性双胞胎研究的结果支持以下观点:面部表情感知受损而不是对所表达情绪的明确识别可能是精神病性症状的神经认知内表型,在临床水平上可能是可靠的。尽管应该需要进行验证性研究,它有助于进一步讨论22q11.2DS中临床表型的病因。