Figure 7. Proximity Index and its relation to behavioral phenotype in children with autism spectrum disorder (ASD) seen two times a year apart.

Sample comprised 81 children with ASD who had valid eye-tracking recording and a complete set of behavioral phenotype measures a year after the baseline (T2). The PI for this paired longitudinal cohort was established using an age-matched reference group of 29 Typically Developing (TD) children. Loadings on the latent component were derived using PLS correlation analysis. The cross-correlation matrix included the Proximity Index (PI) on the imaging side A and three behavioral variables on the B side. The behavioral matrix accounted for two domains of autistic symptoms as assessed by ADOS-2, Verbal and Preverbal Cognition (VPC) from the PEP-3, and the Adaptive Behavior Composite Score from the VABS-II. Error bars represent the bootstrapping 5th to 95th percentiles. Results that were not robust are indicated by a gray boxplot color. (A) Proximity index (PI) obtained at T1 and phenotype measures obtained a year later (T2). PI at T1 positively correlated with reduced symptoms at T2 (B) Simultaneous PLS-C: both PI and phenotype measures were obtained at T2. PI at T2 positively correlated with symptoms at T2 and positively with adaptive behavior. Loading on the latent component was obtained using the partial least squares correlation analysis. The cross-correlation matrix was composed of the proximity index-PI on the imaging A and three variables on the behavior B side. The behavior matrix included two domains of autistic symptoms assessed by ADOS-2, Verbal and preverbal cognition (VPC) of PEP-3, and the Adaptive Behavior Composite Score of VABS-II.