An investigation of white matter integrity and attention deficits following traumatic brain injury

Objective: This study aimed to investigate the association between white matter tracts and multiple aspects of attention and working memory deficits in a relatively acute traumatic brain injury (TBI) sample. Method: Neuropsychological measures of attention and working memory were administered to 20 participants with complicated mild-to-very severe TBI and 20 control participants. Tract-based spatial statistics was used to assess fractional anisotropy (FA) and mean diffusivity (MD) of white matter tracts for 15 TBI participants and 20 controls. Results: When compared to controls, participants with TBI were found to have lower FA (p < 0.001) and higher MD (p < 0.001) values in the majority of white matter tracts. TBI participants were also slower to complete tasks including Trail Making Test, Hayling, computerized Selective Attention Task, n-back and Symbol Digit Modalities Test (p < 0.001), when compared to controls. When controlling for age and estimated premorbid intelligence, slowed information processing speed following TBI was found to be associated with FA values in the corpus callosum, superior longitudinal fasciculus, cingulum, inferior fronto-occipital fasciculi, corona radiata and cerebral white matter. Conclusion: The results highlight the widespread damage associated with TBI, as well as the impact of these alterations on information processing speed.