Sensory Processing in Autism: A Review of Neurophysiologic Findings

Summary & key facts

This review summarizes brain-based studies of how people with autism sense sound, touch, and sight. It reports that unusual sensory reactions are very common (over 96% of children with ASD) and that many EEG, MEG, and fMRI studies find atypical brain responses early in the sensory pathway. Findings are mixed across studies and methods, and the authors say that clearer neurophysiologic profiles could become biomarkers for diagnosis or tracking treatments, but more and better research is needed.

Key facts:

• More than 96% of children with autism spectrum disorders report hyper- and hyposensitivities in multiple sensory domains.
• Studies of the auditory brainstem response give mixed results: some find no differences in transmission time, while others report prolonged III–V inter-peak latency in children and adolescents with ASD.
• Cortical auditory studies using EEG and MEG commonly show atypical timing in early peaks (~110–150 ms), but some studies report faster cortical latencies and others report delayed latencies depending on the tones and methods used.
• In adults with Asperger syndrome, lower tactile perceptual thresholds were found for 200 Hz but not 30 Hz vibrotactile stimuli, suggesting a specific hypersensitivity in the Pacinian-corpuscle pathway.
• A small tactile study in children (only six boys) found no threshold differences for some vibrotactile tests, which limits confidence in that result.
• MEG studies in high-functioning adults with autism showed disrupted cortical maps for the face and hand in somatosensory cortex.
• The review emphasizes large heterogeneity in autism (different causes, ages, and symptom severity), and says this heterogeneity likely contributes to the inconsistent neurophysiologic findings across studies.

Topics

Attention Deficit Hyperactivity Disorder Autism Spectrum Disorder Research EEG and Brain-Computer Interfaces

Categories

Cognitive Neuroscience Life Sciences Neuroscience

Tags

Autism Autism spectrum disorder Developmental psychology Electroencephalography Magnetoencephalography Neuroimaging Neurophysiology Neuroscience Psychology Sensory processing Sensory system