Orekhova Elena V, Elsabbagh Mayada, Jones Emily Jh, Dawson Geraldine, Charman Tony, Johnson Mark H
Centre for Brain and Cognitive Development, School of Psychology, Birkbeck, University of London, Henry Welcome Building, London, WC1E 7HX UK.
Department of Psychiatry, McGill University, Montreal, PQ H3A 1A1 Canada.
J Neurodev Disord. 2014;6(1):40. doi: 10.1186/1866-1955-6-40. Epub 2014 Nov 7.
It has been previously reported that structural and functional brain connectivity in individuals with autism spectrum disorders (ASD) is atypical and may vary with age. However, to date, no measures of functional connectivity measured within the first 2 years have specifically associated with a later ASD diagnosis.
In the present study, we analyzed functional brain connectivity in 14-month-old infants at high and low familial risk for ASD using electroencephalography (EEG). EEG was recorded while infants attended to videos. Connectivity was assessed using debiased weighted phase lag index (dbWPLI). At 36 months, the high-risk infants were assessed for symptoms of ASD.
As a group, high-risk infants who were later diagnosed with ASD demonstrated elevated phase-lagged alpha-range connectivity as compared to both low-risk infants and high-risk infants who did not go on to ASD. Hyper-connectivity was most prominent over frontal and central areas. The degree of hyper-connectivity at 14 months strongly correlated with the severity of restricted and repetitive behaviors in participants with ASD at 3 years. These effects were not attributable to differences in behavior during the EEG session or to differences in spectral power.
The results suggest that early hyper-connectivity in the alpha frequency range is an important feature of the ASD neurophysiological phenotype.
此前已有报道称，自闭症谱系障碍（ASD）患者的大脑结构和功能连接存在异常，且可能随年龄变化。然而，迄今为止，在出生后头两年内测量的功能连接指标中，尚无一项与后期的ASD诊断有特定关联。
在本研究中，我们使用脑电图（EEG）分析了14个月大的、患ASD高家族风险和低家族风险婴儿的大脑功能连接。在婴儿观看视频时记录EEG。使用去偏加权相位滞后指数（dbWPLI）评估连接性。在36个月时，对高风险婴儿进行ASD症状评估。
总体而言，与低风险婴儿以及未发展为ASD的高风险婴儿相比，后来被诊断为ASD的高风险婴儿表现出更高的α波段相位滞后连接性。过度连接在额叶和中央区域最为明显。14个月时的过度连接程度与3岁时ASD参与者的受限和重复行为严重程度密切相关。这些影响并非归因于EEG记录期间的行为差异或频谱功率差异。
结果表明，α频率范围内的早期过度连接是ASD神经生理表型的一个重要特征。
