经颅磁刺激治疗后孤独症谱系障碍儿童表情识别过程神经活动的变化

Effect of transcranial magnetic stimulation on neural activity during expression recognition in children with autism spectrum disorder

目的:探讨低频重复经颅磁刺激(rTMS)对孤独症谱系障碍(ASD)儿童表情识别过程中前额叶皮质(PFC)氧合血红蛋白(HbO)浓度的影响。方法:选取15例符合美国精神障碍诊断与统计手册第4版(DSM-IV)诊断标准的汉族ASD儿童15例,平均年龄为(73±25)月。用fNIRS检测进行表情识别任务时PFC的HbO浓度,经12周rTMS治疗后复测fNIRS;rTMS刺激部位包括左侧Broca区、左侧额前、左枕叶,频率为1Hz。结果:治疗后,ASD儿童识别高兴表情时,左背外侧PFC的HbO水平下降(P<0.05),右背外侧PFC的HbO水平升高(P<0.05);识别悲伤表情时,各通道HbO水平变化无统计学意义(均P>0.05);识别中性表情时,左腹外侧PFC(P<0.05)、左后侧PFC(P<0.01)HbO水平下降,左背外侧PFC、右眶额叶HbO水平升高(均P<0.05)。结论:低频rTMS可能影响ASD儿童表情识别过程神经功能活动。

Objective: To explore the alteration of oxyhemoglobin level in prefrontal cortex(PFC) during facial expression recognition in children with autism spectrum disorder(ASD) after transcranial magnetic stimulation(rTMS) by using functional near infrared imaging spectroscopy(fNIRS). Methods: Totally 15 Chinese Han children with ASD who met the criteria of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition(DSM-Ⅳ) were enrolled,including 10 boys and 5 girls,with an average age of(73±25) months. All the participants received fNIRS assessments using facial expression recognition paradigm to detect oxyhemoglobin levels in PFC. After rTMS administration of low frequency( 1 Hz) over the left Broca area,left anterior frontal area and left occipital lobe for 12 weeks,fNIRS was reassessed. Results: After rTMS treatment,the oxyhemoglobin level in channel 2(left dorsolateral prefrontal cortex, left DLPFC) decreased significantly(P < 0. 05) and the oxyhemoglobin level in channel 18(right DLPFC) increased significantly(P <0.05) in the happy expression recognition task. The oxyhemoglobin level in each channel showed no alterations significantly(P>0.05) in the sad expression recognition task. In the neutral expression recognition task, the oxyhemoglobin level in channel 1(left ventrolateral PFC)(P <0. 05) and channel 8(left posterior PFC)(P <0. 01) decreased significantly,and the oxyhemoglobin level in channel 2( left DLPFC)( P < 0. 05) and channel 16( right orbitofrontal cortex)( P < 0.05) increased significantly. Conclusion: Low frequency rTMS might influence the neural function in the process of facial expression recognition among children with ASD.