Evaluation of mismatch negativity as a marker for language impairment in autism spectrum disorder.

Background: The identification of an early and objective marker of language impairment in autism spectrum disorder (ASD) has the potential to lead to earlier language intervention for affected children. The mismatch negativity (MMN), a passive auditory evoked potential, offers insight into the brain's ability to direct attention to novel sounds. Since exposure to speech is necessary for learning to map meaning onto phonemes, we predicted slower MMN responses to speech sounds would indicate presence of language impairment in ASD.

Visually Evoked Response Differences to Contrast and Motion in Children with Autism Spectrum Disorder.

High-density electroencephalography (EEG) was used to examine the utility of the P1 event-related potential (ERP) as a marker of visual motion sensitivity to luminance defined low-spatial frequency drifting gratings in 16 children with autism and 16 neurotypical children. Children with autism displayed enhanced sensitivity to large, high-contrast low-spatial frequency stimuli as indexed by significantly shorter P1 response latencies to large vs. small gratings.