Taste processing in autism spectrum disorder: A translational scoping review

Area of Science:

• Neuroscience
• Developmental Psychology
• Sensory Science

Background:

• Autism spectrum disorder (ASD) involves social and behavioral challenges, often with sensory atypicalities.
• Taste processing is crucial for food evaluation but is understudied in ASD, impacting understanding of selective eating and nutrition.
• Understanding gustatory functioning in ASD is vital for addressing associated health and behavioral issues.

Purpose of the Study:

• To conduct a scoping review of research on gustatory functioning in autism spectrum disorder (ASD).
• To synthesize findings from human studies (questionnaires, neuroimaging, psychophysical tests) and animal models.
• To identify research gaps in the chemosensory profile of individuals with ASD.

Main Methods:

• Systematic literature search across four databases for human studies and animal models.
• Categorization of human studies by methodology: questionnaires, neuroimaging, and psychophysical tests.
• Inclusion of eight animal model studies for cross-species comparative insights.

Main Results:

• Questionnaire data suggest differences in taste reactivity in individuals with ASD.
• Neuroimaging indicates potential involvement of the hippocampus and aSTS connectivity in atypical taste processing.
• Psychophysical and animal studies reveal variability in taste preferences, with a notable aversion to bitterness and altered sweetness perception in ASD.

Conclusions:

• Individuals with ASD exhibit distinct patterns in taste processing, including bitterness aversion.
• Specific brain regions and connectivity may underlie atypical gustatory function in ASD.
• Significant research gaps exist for understanding saltiness, sourness, and umami in ASD, necessitating further investigation.