Associations of subclinical autistic-like traits with brain structural variation using diffusion tensor imaging and...

Area of Science:

• Neuroimaging
• Autism Spectrum Disorder Research
• Brain Structure and Function

Background:

• Previous studies link autistic spectrum disorder (ASD) to altered brain structures like frontal/temporal cortex volumes and reduced fractional anisotropy (FA) in the inferior fronto-occipital fasciculus.
• The relationship between subclinical autistic-like traits and variations in these brain structures remains largely unexplored.

Purpose of the Study:

• To investigate the association between subclinical autistic-like traits and brain structural variations in psychiatrically healthy individuals.
• To explore how specific autistic traits, measured by the Autism Spectrum Quotient (AQ), relate to white matter integrity and gray matter volume.

Main Methods:

• Analyzed magnetic resonance imaging (MRI) data from 250 healthy subjects phenotyped using the Autism Spectrum Quotient (AQ).
• Employed voxel-based morphometry of T1-MRIs and tract-based spatial statistics for diffusion tensor imaging data analysis.

Main Results:

• The AQ attention switching subscale negatively correlated with FA in the uncinate and inferior fronto-occipital fasciculi.
• Higher AQ attention switching scores were linked to increased mean and radial diffusivity in the uncinate fasciculus.
• The AQ attention to detail subscale positively correlated with gray matter volume in the right pre- and postcentral gyrus.

Conclusions:

• Individuals with higher autistic-like features exhibit decreased white matter integrity in visual processing tracts and increased cortical volume in areas related to motor sequencing and working memory.
• These findings mirror brain alterations seen in diagnosed ASD, supporting a subclinical continuum perspective.
• The study provides insights into the etiology and pathogenesis of ASD.