Functional Connectivity Between the Temporoparietal Cortex and Cerebellum in Autism Spectrum Disorder

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Cognitive Neuroscience

Background:

• Autism spectrum disorder (ASD) is characterized by social deficits and is associated with cerebellar abnormalities.
• The neural underpinnings of ASD, particularly concerning social cognition, remain incompletely understood.
• The temporoparietal junction (TPJ) is critical for social cognition and integrates multimodal information.

Purpose of the Study:

• To investigate the organization and cerebellar connectivity of the temporoparietal junction (TPJ) in adolescents with and without ASD.
• To identify potential neural mechanisms contributing to social deficits in ASD by examining TPJ-cerebellar interactions.
• To explore potential therapeutic targets for ASD based on identified neural connectivity differences.

Main Methods:

• Resting-state functional magnetic resonance imaging (fMRI) data from autistic and neurotypical adolescents were analyzed.
• Localized independent component analysis (ICA) was used to parcellate the bilateral TPJ into independent components (ICs).
• Functional connectivity analysis was performed using TPJ IC time courses as seeds to map cerebellar connections.

Main Results:

• The organization of the TPJ was found to be similar between autistic and neurotypical adolescents.
• A detailed, lateralized map of TPJ subdivisions within the cerebellum was identified.
• A significant difference was observed in ASD: reduced functional connectivity between the right dorsal TPJ and the left Crus II.

Conclusions:

• Cerebellar connectivity with the TPJ is altered in ASD, specifically a diminished connection between the right dorsal TPJ and left Crus II.
• This disturbed cerebellar input to a key social cognition region may underlie social deficits observed in ASD.
• The identified right TPJ-left Crus II pathway represents a potential target for noninvasive brain stimulation therapies aimed at ameliorating ASD symptoms.