Altered thalamotemporal structural connectivity is associated with autistic traits in children with ASD.

Background: Thalamocortical functional and structural connectivity alterations may contribute to clinical phenotype of Autism Spectrum Disorder. As previous studies focused mainly on thalamofrontal connections, we comprehensively investigated between-group differences of thalamic functional networks and white matter pathways projecting also to temporal, parietal, occipital lobes and their associations with core and co-occurring conditions of this population.

Methods: A total of 38 children (19 with Autism Spectrum Disorder) underwent magnetic resonance imaging and behavioral assessment. Functional and structural scans were processed to analyze between-group thalamic connectivity differences and their relationships to measurements of autistic traits and language abilities.

Results: No functional differences were found between groups across 20 networks in each hemisphere. However, we showed diffusion properties of thalamocortical pathways projecting right and left temporal lobes to be disrupted in children with Autism Spectrum Disorder. Additionally, there was a significant association between diffusion differences of thalamotemporal tracts and severity of autistic traits.

Conclusions: Our findings on altered thalamotemporal structural but not functional connectivity contribute to the understanding of white matter organization of thalamocortical pathways in children with Autism Spectrum Disorder.