Objectives: To evaluate group differences between very preterm and full term infants in early symptomology related to ASD (AOSI) at 6 and 12 months gestationally corrected age (GCA) and infants' neural responses (event-related potentials [ERP]) to direct versus averted gaze at 6m. Also, to examine associations between AOSI score, gaze ERP and infants’ general cognitive, motor and language development (Bayley III) at 12m.
Methods: Early behavioural signs of ASD were measured in VP infants (25-31 weeks GCA) and full term controls (37-42 weeks) with no family history of ASD at both 6 and 12 months using the AOSI assessment. Total scores and total ‘marker’ counts (i.e., items scored non-zero) were computed for each child. At 6m, infants’ ERPs were recorded in response to viewing faces with eye gaze directed toward versus away from the infant. Analyses included various relevant components in the ERP (P1, N290 and P400). Developmental functioning (cognitive, motor and expressive/receptive language) was measured at 12 months for both preterm and full-term infants using the Bayley III assessment.
Results: Preliminary results from 15 full term and 9 VP infants indicate that relative to full term controls, VP infants show more early behavioural signs (higher Total Scores and more Markers) of ASD on the AOSI. Higher AOSI scores amongst VP infants are associated with lower developmental functioning scores on the Bayley III, but not with abnormal evoked responses to dynamic gaze shifts.
Conclusions: Within the first year, preterm infants show more behavioural signs associated with ASD on the AOSI, demonstrating scores in a similar range to high-risk siblings later diagnosed with ASD. However, higher AOSI scores in VP infants may reflect more non-specific behaviours associated with developmental delay, rather than a true early autism phenotype. Further follow-up will be important to distinguish whether behavioural abnormalities predict later ASD symptoms/diagnoses and/or non-ASD related impairments in this VP cohort.
See more of: Clinical Phenotype
See more of: Symptoms, Diagnosis & Phenotype