A Diffusion Tensor Imaging Study: Relation of Wisconsin Card Sorting Covariates to White Matter Abnormalities in Traumatic Brain Injury

New brain imaging modalities and neuropsychological testing tools are used to study neuronal changes in brain disorders such as mild traumatic brain injury (mTBI). Here we utilized diffusion tensor imaging (DTI) and Wisconsin Card Sorting Test (WCST) covariates to investigate patients with chronic mTBI. Neuropsychological assessments for mTBI are used to evaluate impairments across a broad spectrum of executive functions. Our study aims to examine the relationship between fractional anisotropy (FA) and WCST covariates in patients with chronic mTBI. We hypothesize that patients who suffered chronic mTBI have significantly reduced fractional anisotropy (FA) in frontal white matter regions in association with their significant deviation from standard percentile scores in WSCT. Utilizing multi-linear regression models alongside analyzing diffusion tensor imaging scans, WCST covariates were linearly regressed to produce positive and negative contrasts to identify specific regions of interest (ROI) with reduced FA. Results show that within a group of chronic mTBI patients, patients whose WCST covariates (such as percentage perseverative responses, conceptual response, categories completed responses) percentile scores significantly deviate beyond standard percentile scores and show lower fractional anisotropy in white matter regions mainly in the frontal cortex including the inferior frontal, superior frontal, and corpus callosum demonstrating executive function deficits that correlated with greater errors. This study investigates the correlation between Wisconsin Card Sorting Test (WCST) covariates and diffusion tensor imaging (DTI) as valuable tools in the diagnostic and prognostic evaluation of patients with a history of chronic traumatic brain injury and persistent cognitive impairment.