Age-related differences in delta-beta phase-amplitude coupling in autistic individuals

Area of Science:

• Neuroscience
• Autism Spectrum Disorder Research
• Electroencephalography (EEG) Analysis

Background:

• Autism Spectrum Disorder (ASD) is characterized by core symptoms, anxiety, and ADHD traits.
• Understanding the neurophysiological underpinnings of ASD is crucial for developing objective biomarkers.
• Phase-Amplitude Coupling (PAC) is a neurophysiological metric that can be extracted from resting-state EEG.

Purpose of the Study:

• To investigate the relationship between core autism symptoms, anxiety, ADHD traits, and Delta-Beta PAC in autistic and non-autistic individuals.
• To examine these relationships across different age groups: children, adolescents, and adults.
• To explore the potential of Delta-Beta PAC as a neurophysiological biomarker for ASD.

Main Methods:

• Analysis of eyes-open resting-state EEG data from 371 individuals.
• Application of a phase de-biasing PAC algorithm for accurate PAC estimation.
• Comparison of PAC values between autistic and non-autistic participants across age groups.

Main Results:

• A significant increase in Delta-Beta PAC was observed in autistic adults meeting diagnostic thresholds (ADOS-2/ADI-R) compared to non-autistic adults.
• No significant differences in Delta-Beta PAC were found in children or adolescent populations.
• A positive correlation was found between Delta-Beta PAC and restricted/repetitive behaviors (ADOS-2) and ADHD hyperactivity/impulsivity in the entire autistic cohort.

Conclusions:

• Neurophysiological differences in Delta-Beta PAC are present in autistic adults meeting diagnostic criteria, suggesting potential age-specific biomarkers.
• Further research is needed to identify autistic neurodiverse subgroups beyond age-based classifications.
• Debiased Delta-Beta PAC (dPAC) shows promise as a potential severity biomarker in the autistic population.