Atypical Processing of Novel Distracters in a Visual Oddball Task in Autism Spectrum Disorder

Area of Science:

• Neuroscience
• Developmental Psychology
• Cognitive Science

Background:

• Children with autism spectrum disorder (ASD) exhibit P3b abnormalities in oddball tasks.
• Impaired habituation to novelty may cause abnormal attention orienting in ASD.

Purpose of the Study:

• To investigate attention orienting to novel distracters in children with ASD using a three-stimulus visual oddball task.
• To test the hypothesis of impaired habituation to novelty in ASD, predicting reduced ERP selectivity and delayed late ERPs.

Main Methods:

• Utilized a three-stimulus visual oddball task with novel distracters.
• Recorded event-related potentials (ERPs) using dense-array EEG in 32 ASD and 24 typically developing (TD) children.
• Analyzed behavioral data (reaction time, accuracy) and ERP components (P1, N1, P3a, P3b).

Main Results:

• Children with ASD had higher error rates and lower error-related negativity.
• ASD group showed elevated parietal P1, frontal N1, P3a, and P3b responses to novel distracters.
• Augmented exogenous ERPs indicated reduced stimulus pre-processing selectivity in ASD.

Conclusions:

• Children with ASD demonstrate impaired habituation to unattended novel stimuli.
• This impairment results in excessive cognitive load during later processing stages and response selection.
• Findings suggest abnormal attention allocation and processing in ASD when differentiating targets from novel distracters.