Resting-state oscillatory activity in autism spectrum disorders.

Lurie Family Foundations MEG Imaging Center, Department of Radiology, Children's Hospital of Philadelphia, 2nd Floor Wood Bldg., Room 2115, Mail Stop W02-1010, Philadelphia, PA 19104-4399, USA.
Journal of Autism and Developmental Disorders (Impact Factor: 3.06). 12/2011; 42(9):1884-94. DOI: 10.1007/s10803-011-1431-6
Source: PubMed

ABSTRACT Neural oscillatory anomalies in autism spectrum disorders (ASD) suggest an excitatory/inhibitory imbalance; however, the nature and clinical relevance of these anomalies are unclear. Whole-cortex magnetoencephalography data were collected while 50 children (27 with ASD, 23 controls) underwent an eyes-closed resting-state exam. A Fast Fourier Transform was applied and oscillatory activity examined from 1 to 120 Hz at 15 regional sources. Associations between oscillatory anomalies and symptom severity were probed. Children with ASD exhibited regionally specific elevations in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), and high frequency (20-120 Hz) power, supporting an imbalance of neural excitation/inhibition as a neurobiological feature of ASD. Increased temporal and parietal alpha power was associated with greater symptom severity and thus is of particular interest.

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