Authors: Amara T. Nkosi, Lena K. Johansson, Raj P. Menon
Journal: Frontiers in Child Neurodevelopment (FCN), ISSN 3155-9611
Citation: FCN 1(1), 2023-02-28.
Type: Original Research
Fragile X syndrome (FXS) is a leading genetic cause of intellectual disability and autism spectrum disorder (ASD), characterized by significant impairments in social communication. Despite extensive behavioral research, the neural underpinnings of social communication deficits in toddlers with FXS remain poorly understood. This study employed functional near-infrared spectroscopy (fNIRS) to examine neural responses during social communication tasks in 24 toddlers with FXS (mean age 28.5 months) and 24 typically developing (TD) controls matched on chronological age. Participants completed a joint attention task and a face processing task while fNIRS data were collected over frontal and temporal regions. Behavioral measures of social communication were assessed using the Brief Observation of Social Communication Change (BOSCC) and the Vineland Adaptive Behavior Scales. Results revealed that toddlers with FXS exhibited reduced activation in the right posterior superior temporal sulcus (pSTS) during joint attention compared to TD controls. Additionally, atypical lateralization of face processing was observed, with diminished left fusiform gyrus activation in the FXS group. Neural activation in the pSTS was significantly correlated with BOSCC social communication scores. These findings provide evidence for early neural markers of social communication dysfunction in FXS and suggest that interventions targeting the pSTS network may be beneficial.
Fragile X syndrome, social communication, functional near-infrared spectroscopy, joint attention, face processing, toddlers, neural correlates