UMR1253, INSERM, Université de Tours, TOURS, France.
Centre Universitaire de Pédopsychiatrie, CHRU de Tours, TOURS, France.
J Neurodev Disord. 2018 Sep 18;10(1):28. doi: 10.1186/s11689-018-9246-9.
Autism spectrum disorder (ASD) is characterized by atypical behaviors in social environments and in reaction to changing events. While this dyad of symptoms is at the core of the pathology along with atypical sensory behaviors, most studies have investigated only one dimension. A focus on the sameness dimension has shown that intolerance to change is related to an atypical pre-attentional detection of irregularity. In the present study, we addressed the same process in response to emotional change in order to evaluate the interplay between alterations of change detection and socio-emotional processing in children and adults with autism.
Brain responses to neutral and emotional prosodic deviancies (mismatch negativity (MMN) and P3a, reflecting change detection and orientation of attention toward change, respectively) were recorded in children and adults with autism and in controls. Comparison of neutral and emotional conditions allowed distinguishing between general deviancy and emotional deviancy effects. Moreover, brain responses to the same neutral and emotional stimuli were recorded when they were not deviants to evaluate the sensory processing of these vocal stimuli.
In controls, change detection was modulated by prosody: in children, this was characterized by a lateralization of emotional MMN to the right hemisphere, and in adults, by an earlier MMN for emotional deviancy than for neutral deviancy. In ASD, an overall atypical change detection was observed with an earlier MMN and a larger P3a compared to controls suggesting an unusual pre-attentional orientation toward any changes in the auditory environment. Moreover, in children with autism, deviancy detection depicted reduced MMN amplitude. In addition in children with autism, contrary to adults with autism, no modulation of the MMN by prosody was present and sensory processing of both neutral and emotional vocal stimuli appeared atypical.
Overall, change detection remains altered in people with autism. However, differences between children and adults with ASD evidence a trend toward normalization of vocal processing and of the automatic detection of emotion deviancy with age.
自闭症谱系障碍(ASD)的特征是在社交环境中和对变化的事件做出反应时表现出异常行为。虽然这一对症状是该疾病的核心,以及异常的感觉行为,但大多数研究只调查了一个维度。对同一性维度的关注表明,对变化的不宽容与对不规则性的非注意前检测异常有关。在本研究中,我们针对情绪变化做出了相同的反应,以评估自闭症儿童和成人的变化检测和社会情感处理之间的相互作用。
在自闭症儿童和成人以及对照组中记录了对中性和情感韵律偏差(不匹配负波(MMN)和 P3a,分别反映变化检测和对变化的注意力定向)的大脑反应。中性和情感条件的比较允许区分一般偏差和情感偏差效应。此外,当相同的中性和情感刺激不是偏差时,记录了它们的大脑反应,以评估这些声音刺激的感觉处理。
在对照组中,韵律变化检测受到调制:在儿童中,这种调制表现为情感 MMN 向右侧的偏侧化,而在成人中,情感偏差的 MMN 比中性偏差更早。在 ASD 中,与对照组相比,整体观察到异常的变化检测,表现为 MMN 更早,P3a 更大,这表明对听觉环境中的任何变化异常的非注意前定向。此外,自闭症儿童的偏差检测显示 MMN 振幅减小。此外,在自闭症儿童中,与自闭症成人相反,韵律对 MMN 没有调节,并且对中性和情感声音刺激的感觉处理均呈现异常。
总的来说,自闭症患者的变化检测仍然异常。然而,自闭症儿童和成人之间的差异表明,随着年龄的增长,声音处理和对情绪偏差的自动检测有趋于正常的趋势。