Department of Radiology, The Children's Hospital of Philadelphia, 34th St. and Civic Center Blvd., Philadelphia, PA 19104, USA.
Autism Res. 2010 Feb;3(1):8-18. doi: 10.1002/aur.111.
Motivated by auditory and speech deficits in autism spectrum disorders (ASD), the frequency dependence of superior temporal gyrus (STG) 50 msec (M50) and 100 msec (M100) neuromagnetic auditory evoked field responses in children with ASD and typically developing controls were evaluated. Whole-cortex magnetoencephalography (MEG) was obtained from 17 typically developing children and 25 children with ASD. Subjects were presented tones with frequencies of 200, 300, 500, and 1,000 Hz, and left and right STG M50 and M100 STG activity was examined. No M50 latency or amplitude Group differences were observed. In the right hemisphere, a Group x Frequency ANOVA on M100 latency produced a main effect for Group (P=0.01), with an average M100 latency delay of 11 msec in children with ASD. In addition, only in the control group was the expected association of earlier M100 latencies in older than younger children observed. Group latency differences remained significant when hierarchical regression analyses partialed out M100 variance associated with age, IQ, and language ability (all P-values <0.05). Examining the right-hemisphere 500 Hz condition (where the largest latency differences were observed), a sensitivity of 75%, a specificity of 81%, and a positive predictive value (PPV) of 86% was obtained at a threshold of 116 msec. The M100 latency delay indicates disruption of encoding simple sensory information. Given similar findings in language impaired and non-language impaired ASD subjects, a right-hemisphere M100 latency delay appears to be an electrophysiological endophenotype for autism.
受自闭症谱系障碍（ASD）听觉和言语缺陷的启发，评估了 ASD 儿童和典型发育对照组中颞上回（STG）50 毫秒（M50）和 100 毫秒（M100）神经磁听觉诱发场反应的频率依赖性。从 17 名典型发育儿童和 25 名 ASD 儿童中获得了整个皮层脑磁图（MEG）。向受试者呈现频率为 200、300、500 和 1000 Hz 的音调，并检查左、右 STG M50 和 M100 STG 活动。未观察到 M50 潜伏期或振幅组间差异。在右半球，M100 潜伏期的组 x 频率 ANOVA 产生了组的主效应（P=0.01），ASD 儿童的平均 M100 潜伏期延迟 11 毫秒。此外，仅在对照组中观察到较年长儿童的 M100 潜伏期较早的预期关联。当分层回归分析偏置与年龄、智商和语言能力相关的 M100 方差时，组潜伏期差异仍然显着（所有 P 值<0.05）。在检查右半球 500 Hz 条件（观察到最大潜伏期差异的条件）时，在 116 毫秒的阈值下，获得了 75%的灵敏度、81%的特异性和 86%的阳性预测值（PPV）。M100 潜伏期延迟表明简单感觉信息编码的中断。鉴于语言障碍和非语言障碍 ASD 受试者中存在类似的发现，右半球 M100 潜伏期延迟似乎是自闭症的一种电生理内表型。
