Abnormal spatiotemporal dynamics of visuospatial working memory processing distinguishes children with Developmental Visual-Spatial Disorder from those with Autism Spectrum Disorder and Typical Development: A HD-EEG Study

Visuospatial working Memory (VSWM) deficits are not only present in Developmental Visuospatial Disorder (DVSD), but they can also be present in Autism Spectrum Disorder (ASD). Here, high-density ERPs were recorded during the spatial capacity delayed response task (SCDRT) in 48 children and adolescents: A DVSD group, a typically developing group (TD), and an ASD group without intellectual disability. The DVSD group was less accurate in the VSWM task relative to TD and ASD groups. Both DVSD and ASD groups showed smaller early P1 waves relative to the TD group. The DVSD group displayed unique abnormalities of the right frontal P2 and N2 waves relative to the TD group, while the ASD group did not. The DVSD group differed from the ASD group for reduced posterior P2 amplitudes. Impaired early perceptual and/or attentional mechanisms, indexed by the early P1 wave, appear to be present in both DVSD and ASD. In contrast, deficits in later top-down feature selection and cognitive control mechanisms, indexed by the anterior P2 and N2 waves, appear to be uniquely present in DVSD. Such results identify possible EEG biomarkers of impaired VSWM performance in DVSD not shared by ASD, supporting the clinical distinction between these two developmental disorders, and confirming that DVSD may affect predominantly right hemisphere connectivity patterns.