Exploring cortical activation and connectivity in infants with and without familial risk for autism during naturalistic social interactions: A preliminary study

• Published in: Infant behavior & development Vol. 57; p. 101337
• Main Authors: Bhat, A.N., McDonald, N.M., Eilbott, J.E., Pelphrey, K.A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2019
• Subjects: Autism spectrum disorder; Autism Spectrum Disorder - diagnostic imaging; Autism Spectrum Disorder - genetics; Autism Spectrum Disorder - psychology; Cerebral Cortex - diagnostic imaging; Cortical activation; Female; fNIRS; Functional connectivity; Genetic Predisposition to Disease - genetics; Genetic Predisposition to Disease - psychology; Humans; Infant; Infants; Interpersonal Relations; Male; Nerve Net - diagnostic imaging; Parent-Child Relations; Proof of Concept Study; Risk Factors; Siblings - psychology; Social interaction; Spectroscopy, Near-Infrared - methods; Functional connectivity; Cortical activation; Infants; fNIRS; Social interaction; Autism spectrum disorder
• ISSN: 0163-6383; 1879-0453; 1934-8800
• DOI: 10.1016/j.infbeh.2019.101337

•Cortical hyper-connectivity in the first year precedes overt signs of ASD seen in the second year.•fNIRS examined functional activation (FA) and connectivity (FC) in high- and low-risk infants.•Compared to LR infants, HR infants showed reduced right and left hemispheric FA in the social period and greater FC in the non-social period.•Early differences in cortical FA and FC may be associated with ASD risk. Behavioral signs of Autism Spectrum Disorder (ASD) are typically observable by the second year of life and a reliable diagnosis of ASD is possible by 2 to 3 years of age. Studying infants with familial risk for ASD allows for the investigation of early signs of ASD risk within the first year. Brain abnormalities such as hyper-connectivity within the first year may precede the overt signs of ASD that emerge later in life. In this preliminary study, we use functional near-infrared spectroscopy (fNIRS), an infant-friendly neuroimaging tool that is relatively robust against motion artifacts, to examine functional activation and connectivity during naturalistic social interactions in 9 high-risk (HR; older sibling with ASD) and 6 low-risk (LR; no family history of ASD) infants from 6 to 9 months of age. We obtained two 30-second baseline periods and a 5-minute social interaction period. HR infants showed reduced right and left-hemispheric activation compared to LR infants based on oxy (HbO2) and deoxy (HHb) signal trends. HR infants also had greater functional connectivity than LR infants during the pre- and post-social periods and showed a drop in connectivity during the social period. Our findings are consistent with previous work suggesting early differences in cortical activation associated with familial risk for ASD, and highlight the promise of fNIRS in evaluating potential markers of ASD risk during naturalistic social contexts.