title: Cognitive fatigue is associated with reduced anterior internal capsule integrity in veterans with history of mild to moderate traumatic brain injury.
abstract: No known studies have directly examined white matter microstructural correlates of cognitive fatigue post-TBI in a Veteran sample. We therefore investigated the relationship between cognitive fatigue and white matter integrity in Veterans with history of mild to moderate TBI (mmTBI). 59 Veterans (TBI = 34, Veteran Controls [VCs] = 25]) with and without history of mmTBI underwent structural 3T DTI scans and completed questionnaires related to cognitive fatigue and psychiatric symptoms. Tractography was employed on six regions of interest, including the anterior and posterior limbs of the internal capsule; genu; body and splenium of the corpus callosum; and cingulum bundle. Group analyses revealed that those with history of mmTBI displayed significantly greater levels of cognitive fatigue relative to those with no history of head injury (p = .02). Within the mmTBI group, independent of psychiatric symptoms, decreased white matter microstructural integrity of the left anterior internal capsule was associated with greater levels of cognitive fatigue (p = .01). Results show that the subjective experience of cognitive fatigue following neurotrauma may be linked to the disruption of striato-thalamo-cortical tracts that are important in mediating arousal and higher-order cognitive processes. These findings build upon those from existing functional neuroimaging studies in those with history of TBI, providing further evidence for the neural basis of cognitive fatigue in head injured adults.
authors.affiliation: Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California, San Diego (SDSU/UCSD), San Diego, CA, USA.|VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.
authors.forename: Alexandra L
authors.initials: AL
authors.lastname: Clark
authors.affiliation: VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.|Center of Excellence for Stress and Mental Health, VASDHS, San Diego, CA, USA.|School of Medicine, Department of Psychiatry, University of California San Diego, La Jolla, CA, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Delano-Wood
authors.affiliation: VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.|School of Medicine, Department of Psychiatry, University of California San Diego, La Jolla, CA, USA.
authors.forename: Scott F
authors.initials: SF
authors.lastname: Sorg
authors.affiliation: Joint Doctoral Program in Clinical Psychology, San Diego State University/University of California, San Diego (SDSU/UCSD), San Diego, CA, USA.|VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.
authors.forename: Madeleine L
authors.initials: ML
authors.lastname: Werhane
authors.affiliation: VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA.|School of Medicine, Department of Psychiatry, University of California San Diego, La Jolla, CA, USA.
authors.forename: Karen L
authors.initials: KL
authors.lastname: Hanson
authors.affiliation: VA San Diego Healthcare System (VASDHS), 3350 La Jolla Village Drive, San Diego, CA, 92161, USA. dschiehser@ucsd.edu.|Center of Excellence for Stress and Mental Health, VASDHS, San Diego, CA, USA. dschiehser@ucsd.edu.|School of Medicine, Department of Psychiatry, University of California San Diego, La Jolla, CA, USA. dschiehser@ucsd.edu.
authors.forename: Dawn M
authors.initials: DM
authors.lastname: Schiehser
mesh_terms: D000328:Adult; D000070642:Brain Injuries, Traumatic / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology / Q000523:psychology; D015331:Cohort Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D020772:Internal Capsule / Q000000981:diagnostic imaging* / Q000473:pathology; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D005222:Mental Fatigue / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000473:pathology; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014728:Veterans; D066127:White Matter / Q000000981:diagnostic imaging / Q000473:pathology
keywords: Cognitive fatigue; Fatigue; TBI; White matter microstructure