Sensory Processing in Autism: A Review of Neurophysiologic Findings

Summary & key facts

This review looked at brain studies of how people with autism sense sounds, touch, and sights. It notes that unusual sensory reactions are very common in autism (reported in over 96% of children) and that brain measures (like ABR, EEG, MEG, and fMRI) often show differences in early auditory pathways and cortical responses. However, the specific findings are mixed across studies and seem to depend on the task, the person’s age and diagnosis, and the methods used.

Key facts:

• Over 96% of children with ASD are reported to have increased or decreased sensitivity (hyper- or hypo-sensitivities) in more than one sensory domain.
• Some studies of auditory brainstem responses (ABR) found no differences between people with ASD and controls, while other studies found longer III–V interpeak latencies in children and adolescents with ASD (a sign of slower conduction in th
• A forward-masking auditory study in adults with Asperger syndrome found a reduced wave III amplitude that separated the Asperger group from control participants and from people with schizophrenia or ADHD.
• Russo and colleagues reported that children with ASD had typical brainstem responses to simple click sounds, but showed differences when sounds varied in pitch or when speech sounds were presented with background noise.
• EEG and MEG studies (which record brain electrical or magnetic signals) often find atypical early cortical auditory responses (peaks occurring in under 150 milliseconds), but some studies report faster peaks and others report delayed peaks
• Two groups (Bruneau et al. and Oram Cardy et al.) reported that earlier and larger right-hemisphere cortical peaks were associated with better language function in their samples, but this relationship is not consistent across all studies.
• The review emphasizes that study differences (age range, specific ASD diagnoses, and experimental methods) likely contribute to inconsistent results, so no single neurophysiologic pattern describes all individuals with ASD.

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