Semantic Processing in Autism Spectrum Disorders Is Associated With the Timing of Language Acquisition: A...

Area of Science:

• Neuroscience
• Developmental Psychology
• Linguistics

Background:

• Individuals with autism spectrum disorder (ASD) often exhibit challenges in understanding ambiguous words, relying on sentence context.
• The neural underpinnings of semantic processing and the impact of developmental language delay in ASD require further investigation.

Purpose of the Study:

• To examine the brain basis of sentence context effects on word understanding in autism spectrum disorder (ASD) and typical development (TD).
• To investigate the neural correlates of a history of developmental language delay in ASD during semantic processing.

Main Methods:

• Magnetoencephalography (MEG) was used to record event-related field responses.
• Analysis focused on early (150 ms) and N400 latencies in response to dominant homonyms, subordinate homonyms, and unambiguous words.

Main Results:

• Typical development (TD) and ASD individuals without language delay showed clear semantic access at early and N400 latencies.
• ASD individuals with a history of language delay exhibited weak, non-significant early semantic access modulation.
• Reduced semantic sensitivity in ASD with language delay was linked to strong right-hemisphere lateralization.

Conclusions:

• Differential neural mechanisms underlie semantic processing in ASD.
• Delayed language acquisition in ASD is associated with altered language processing and lateralization.