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EEG power at 3 months in infants at high familial risk for autism
April R Levin1,2,3, Kandice J Varcin4,5, Heather M O'Leary6
1Boston Children's Hospital, 300 Longwood Avenue, BCH 3213, Boston, MA, 02115, USA. april.levin@childrens.harvard.edu.
Insights
Infants at high familial risk for autism show reduced frontal electroencephalographic (EEG) power by 3 months. This early brain activity difference predicts poorer expressive language development by 12 months.
Area of Science:
- Neurodevelopmental disorders
- Infant brain development
- Autism spectrum disorder (ASD) research
Background:
- Infant brain development alterations may precede developmental disorder diagnosis.
- Infants at high risk for autism also face increased risk for language disorders.
- Early identification of neurodevelopmental trajectories is crucial.
Purpose of the Study:
- To assess electroencephalographic (EEG) differences in 3-month-old infants at high versus low familial risk for autism.
- To determine the predictive significance of 3-month EEG power for later developmental outcomes.
Main Methods:
- Prospective, longitudinal study of infant siblings of children with autism (high risk) and typically developing children (low risk).
- EEG data acquired at 3 months; developmental assessments conducted from 6 to 36 months.
- Statistical analysis of relationships between 3-month frontal EEG power and later developmental outcomes, including autism diagnosis and language development.
Main Results:
- Infants at high familial risk for autism exhibited reduced frontal EEG power across several frequency bands at 3 months compared to low-risk infants.
- Reduced frontal high-alpha power at 3 months was significantly associated with poorer expressive language skills at 12 months.
Conclusions:
- Reduced frontal EEG power in early infancy may signal an elevated risk for impaired expressive language development.
- These findings support the concept of reduced power as a potential biomarker for atypical brain function in infants at risk for autism.
- Altered developmental trajectories in infants at familial risk for autism extend beyond autism-specific domains.
Background:
Alterations in brain development during infancy may precede the behavioral manifestation of developmental disorders. Infants at increased risk for autism are also at increased risk for other developmental disorders, including, quite commonly, language disorders. Here we assess the extent to which electroencephalographic (EEG) differences in infants at high versus low familial risk for autism are present by 3 months of age, and elucidate the functional significance of EEG power at 3 months in predicting later development.
Methods:
EEG data were acquired at 3 months in infant siblings of children with autism (high risk; n = 29) and infant siblings of typically developing children (low risk; n = 19) as part of a prospective, longitudinal investigation. Development across multiple domains was assessed at 6, 9, 12, 18, 24, and 36 months. Diagnosis of autism was determined at 18-36 months. We assessed relationships between 3-month-olds' frontal EEG power and autism risk, autism outcome, language development, and development in other domains.
Results:
Infants at high familial risk for autism had reduced frontal power at 3 months compared to infants at low familial risk for autism, across several frequency bands. Reduced frontal high-alpha power at 3 months was robustly associated with poorer expressive language at 12 months.
Conclusions:
Reduced frontal power at 3 months may indicate increased risk for reduced expressive language skills at 12 months. This finding aligns with prior studies suggesting reduced power is a marker for atypical brain function, and infants at familial risk for autism are also at increased risk for altered developmental functioning in non-autism-specific domains.
