Edgar J Christopher, Fisk Iv Charles L, Berman Jeffrey I, Chudnovskaya Darina, Liu Song, Pandey Juhi, Herrington John D, Port Russell G, Schultz Robert T, Roberts Timothy P L
Lurie Family Foundations MEG Imaging Center, Department of Radiology, Children's Hospital of Philadelphia, 34th and Civic Center Blvd, Wood Building, Suite 2115, Philadelphia, PA 19104 USA.
Center for Autism Research, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA USA.
Mol Autism. 2015 Dec 30;6:69. doi: 10.1186/s13229-015-0065-5. eCollection 2015.
Findings of auditory abnormalities in children with autism spectrum disorder (ASD) include delayed superior temporal gyrus auditory responses, pre- and post-stimulus superior temporal gyrus (STG) auditory oscillatory abnormalities, and atypical hemispheric lateralization. These abnormalities are likely associated with abnormal brain maturation. To better understand changes in brain activity as a function of age, the present study investigated associations between age and STG auditory time-domain and time-frequency neural activity.
While 306-channel magnetoencephalography (MEG) data were recorded, 500- and 1000-Hz tones of 300-ms duration were binaurally presented. Evaluable data were obtained from 63 typically developing children (TDC) (6 to 14 years old) and 52 children with ASD (6 to 14 years old). T1-weighted structural MRI was obtained, and a source model created using single dipoles anatomically constrained to each participant's left and right STG. Using this source model, left and right 50-ms (M50), 100-ms (M100), and 200-ms (M200) time-domain and time-frequency measures (total power (TP) and inter-trial coherence (ITC)) were obtained.
Paired t tests showed a right STG M100 latency delay in ASD versus TDC (significant for right 500 Hz and marginally significant for right 1000 Hz). In the left and right STG, time-frequency analyses showed a greater pre- to post-stimulus increase in 4- to 16-Hz TP for both tones in ASD versus TDC after 150 ms. In the right STG, greater post-stimulus 4- to 16-Hz ITC for both tones was observed in TDC versus ASD after 200 ms. Analyses of age effects suggested M200 group differences that were due to a maturational delay in ASD, with left and right M200 decreasing with age in TDC but significantly less so in ASD. Additional evidence indicating delayed maturation of auditory cortex in ASD included atypical hemispheric functional asymmetries, including a right versus left M100 latency advantage in TDC but not ASD, and a stronger left than right M50 response in TDC but not ASD.
Present findings indicated maturational abnormalities in the development of primary/secondary auditory areas in children with ASD. It is hypothesized that a longitudinal investigation of the maturation of auditory network activity will indicate delayed development of each component of the auditory processing system in ASD.
自闭症谱系障碍（ASD）儿童的听觉异常表现包括颞上回听觉反应延迟、刺激前后颞上回（STG）听觉振荡异常以及非典型的半球侧化。这些异常可能与大脑发育异常有关。为了更好地理解大脑活动随年龄的变化，本研究调查了年龄与STG听觉时域和时频神经活动之间的关联。
在记录306通道脑磁图（MEG）数据时，双耳呈现持续300毫秒的500赫兹和1000赫兹纯音。从63名发育正常儿童（TDC）（6至14岁）和52名ASD儿童（6至14岁）中获取了可评估数据。获取了T1加权结构MRI，并使用单偶极子创建了源模型，该偶极子在解剖学上被约束于每个参与者的左右STG。使用该源模型，获取了左右50毫秒（M50）、100毫秒（M100）和200毫秒（M200）的时域和时频测量值（总功率（TP）和试间相干性（ITC））。
配对t检验显示，与TDC相比，ASD儿童右STG的M100潜伏期延迟（右500赫兹时显著，右1000赫兹时边缘显著）。在左右STG中，时频分析显示，150毫秒后，与TDC相比，ASD儿童对两种纯音的4至16赫兹TP在刺激前后的增加更大。在右STG中，200毫秒后，与ASD相比，TDC对两种纯音的刺激后4至16赫兹ITC更大。年龄效应分析表明，M200组间差异是由于ASD存在成熟延迟，TDC中左右M200随年龄下降，但ASD中下降明显较少。表明ASD听觉皮层成熟延迟的其他证据包括非典型的半球功能不对称，包括TDC中右M100潜伏期比左长，但ASD中没有；以及TDC中左M50反应比右强，但ASD中没有。
目前的研究结果表明，ASD儿童初级/次级听觉区域发育存在成熟异常。据推测，对听觉网络活动成熟的纵向研究将表明ASD中听觉处理系统各组成部分的发育延迟。
