节点文献
自闭症幼儿面孔加工特点的眼动研究:社会认知缺陷指标的探索
Eye Movement Study on Face Processing in Young Children with Autim:the Probe into the Indicators of Social Cognition Deficits
【作者】 陈顺森;
【导师】 白学军;
【作者基本信息】 天津师范大学 , 发展与教育心理学, 2012, 博士
【摘要】 自闭症谱系障碍(autism spectrum disorders, ASDs)是一组有神经基础的广泛性发育障碍(pervasive developmental disorders, PDD),其共同特征是普遍存在社会交往障碍、言语和非言语交流缺陷、兴趣狭窄和行为刻板等临床表现,其中社交障碍是该障碍的核心特异性症状。自闭症处于该谱系障碍最严重的一端。ASD的高发病率迫切需要早期识别、诊断性评估和有根据的干预。确定自闭症幼儿与正常发展儿童的鉴别性受损情况,对该症候群的早期诊断、揭示该谱系障碍的本质具有重要意义。面孔是最重要的社交线索,面孔加工的有效性是个体社交能力的核心。为了收集自闭症早期社会认知指标,由三级甲等精神专科医院儿科主任医师根据《中国精神障碍分类与诊断标准(第三版)》(CCMD-Ⅲ)和《儿童自闭症评定量表》(CARS),选取典型低功能自闭症幼儿为实验组,以实足年龄、视敏度、性别相匹配的正常幼儿为对照组,采用眼动追踪技术,探讨自闭症幼儿面孔加工特点。从场景中觉察到面孔是从面孔中获得社交信号至关重要的一步。因此,研究一包括实验1至实验4,让被试完成一系列面孔觉察与加工任务,与非面孔刺激对比,探讨被试对面孔的选择性注意。结果发现,自闭症幼儿觉察目标物(包括面孔和非面孔)速度显著慢于正常组;自闭症幼儿与正常幼儿一样,觉察无生命物体的时间长于觉察面孔的时间,表现出对面孔的注意偏向;自闭症幼儿对面孔的觉察与加工不受背景-面孔关系变化的影响,但正常幼儿却受此影响。研究二包括实验5和实验6,旨在探讨自闭症幼儿面孔感知与加工的特点。结果发现,自闭症幼儿与正常幼儿一样能够区分面孔刺激和非面孔刺激;自闭症幼儿观看面孔的时间比正常幼儿短,主要表现为对眼睛区域注视显著短于正常幼儿,尤其是对左侧眼睛区域缺少自发注视偏向,但对嘴巴区域以及非特征区的注视与正常组无异。研究三由实验7和实验8构成,探讨自闭症幼儿对熟悉面孔、刚熟悉面孔与陌生面孔的注意和加工的模式,结果发现,自闭症幼儿与正常幼儿一样,能区别对待熟悉面孔与陌生面孔,自闭症幼儿对熟悉面孔的观看时间与正常幼儿无显著差异;不论面孔熟悉程度,自闭症幼儿对面孔的注视时间均显著少于正常幼儿,主要表现在对眼睛区域尤其是左侧眼睛的注视时间较少。研究四包括实验9、实验10和实验11,主要探讨自我面孔识别与加工。结果发现,参照正常幼儿的发展模式,自闭症幼儿自我意识发展延缓,自我-他人分化不足;正常幼儿最快觉察到的不是自我面孔,但对自我面孔的注视时间最长,而自闭症幼儿对自我面孔与他人面孔注视时间没有差异;不论是自我面孔还是他人面孔,自闭症幼儿观看面孔的时间都比正常幼儿短,主要表现在对眼睛区域尤其是左侧眼睛的注视时间较少。研究五包括实验12、实验13和实验14,探讨自闭症幼儿的面孔表情识别与加工,结果发现,自闭症幼儿与正常幼儿一样能够识别基本情绪;自闭症幼儿对不同表情而孔的注视时间都比正常幼儿短,主要表现为对眼睛的注视时间较少;自闭症幼儿与正常幼儿一样,观看恐惧面孔的时间长于中性面孔,注视不同表情眼睛的时间均长于注视嘴巴的时间,对不同表情面孔的注视分配方式与正常幼儿相似。自闭症幼儿对左侧眼睛区域注视不足可能是其右脑加工面孔信息存在缺陷。因此,可以将自闭症幼儿对眼睛区域注视的减少作为早期行为的标记和对自闭症高危人群早期鉴别的指标。依据面孔加工阶段模型,本研究结果表明,自闭症幼儿在面孔选择性注意、面孔识别、面孔加工理解等环节的表现都比正常儿童差。因此,在实践中可根据该模型对自闭症幼儿开展训练。
【Abstract】 Autism spectrum disorders (ASD) are referred to as pervasive developmental disorders (PDD), characterized by pervasive deficits in social interaction, social communication, as well as unusual repetitive or restrictive behaviors and interests, the deficits in reciprocal social interaction is the core specific symptom. Autistic disorder (AD) is the most severe symptom in the spectrum. The increase in ASD prevalence highlights the urgency of paying close attention to early identification, diagnostic assessment, and well-founded interventions. Identifying impairments that distinguish young children with autism from typically developing children allows for early identification and sheds light on the nature of this disorder. The most important social cue is human face, which must be successfully recognised and interpreted as communicative signals. Efficient face processing is the core of social skills.To collect early signals of social cognition deficits of AD children, the current research adopted eye tracking technology to explore the features of face processing in young childern with autism. Preschool children with low-functioning autism were selected by pediatric specialist who serve in one tertiary special mental health hospital according to the Chinese classification and diagnostic criteria of mental disorders,3rd ed.(CCMD-Ⅲ) and the childhood autism rating scale (CARS). Chosen typically developing children as control group were matched with AD children on chronological age, visual acuity, and gender.Detecting a face within a scene is a crucial step in obtaining the social information expressed by the face. Therefore, in Study1including Experiment1to4, a serial of face detection and processing tasks were used to examine children’s selective attention for face compared to non-face stimuli in the scene. The results showed a significant group difference with respect to detection speed to either faces or non-face objects. The autism children took significantly longer time to locate their fixations at the face or non-face targets than those of the control group; both groups showed an attentional bias for face versus non-face as shown they took less time to detect face than inanimate object in the natural scene; the semantic consistency between face and scene background affected face detection and processing of the autism children but not the control group.Study2investgated the face perception and processing in autism in which Experiment5and6was included. The results showed that autism children were able to distinguish face from non-face stimuli, however, they showed shorter face looking time compared to control group.Autism children fixated shorter in the eye region, especially, in contrast to the control group, autism children were not spontaneously biased to the left eye region. However, there was no difference in fixation times in the nonfeature areas and mouth region between individuals with or without autism disorder.Study3, comprised of Experiment7and8, investigated the attention and processing patterns of unfamiliar faces, highly familiar faces and repeated previously unfamiliar faces in autism. The results suggested that children with autism have the ability to distinguish familiar versus unfamiliar face, and they spent the same time to look at the familiar faces compared with normal children. Autism children spent shorter fixation times on all faces compared with normal children, they fixated shorter in the eye region, especially the left eye.Subsequent Study4, comprised of Experiment9,10and11, explored self-face recognition and processing. The results showed no differences between the fixation times of self and other’s face in autism children while the fixation times of self-face was longer in normal children even it is not fixated with priority therefore, there might be a lack of self-other differentiation in autism children compared to the typically developing children, indicated that the development of self-aware in autism might be delayed. Autism children spent less time looking at the faces compared with normal children, no matter it is a self or other’s face, they look less in the eye region, especially were less biased to the left eye region.The last study focused on the recognition and processing of facial expression through Experiment12to14. The results showed that, autistic children were able to recognize basic emotions, however, they fixated at the faces shorter than the control group when viewing different emotional faces, especially to the eye region. Similar to control group, autism children fixated significantly longer at fear faces than neutral faces, longer at eyes than mouths, indicated that their attention allocation patterns to different facial expressions were similar to those of normal children.Autism children showed a lack of fixations in the left eye region might result from their right hemisphere’s deficits for facial information processing. Therefore, it is practicable to use the reduced fixation times in the eye region as an early behavioural indicator, as well as a marker to early indentify autistic individuals from people with high risk of suffering from autism.According to the face processing stages model, the current study demonstrated that autism children had more difficulties than typically developing individuals in face processing stages such as face selective attention, face recognition and understanding of facial cues. Nevertheless, autism children could be trained to be face processing experts base on this model.
【Key words】 autism; face processing; selective attention; recognition of facial identity; recognition of facial expression; left visual field bias;