title: Brain lesion correlates of fatigue in individuals with traumatic brain injury.
abstract: The purpose of this study was to investigate the neurological correlates of both subjective fatigue as well as objective fatigability in individuals with traumatic brain injury (TBI). The study has a cross-sectional design. Participants (N = 53) with TBI (77% male, mean age at injury 38 years, mean time since injury 1.8 years) underwent a structural magnetic resonance imaging (MRI) scan and completed the Fatigue Severity Scale (FSS), while a subsample (N = 36) was also tested with a vigilance task. While subjective fatigue (FSS) was not related to measures of brain lesions, multilevel analyses showed that a change in the participants' decision time was significantly predicted by grey matter (GM) lesions in the right frontal lobe. The time-dependent development of the participants' error rate was predicted by total brain white matter (WM) lesion volumes, as well as right temporal GM and WM lesion volumes. These findings could be explained by decreased functional connectivity of attentional networks, which results in accelerated exhaustion during cognitive task performance. The disparate nature of objectively measurable fatigability on the one hand and the subjective experience of fatigue on the other needs further investigation.
authors.affiliation: a Department of Rehabilitation Psychology , Institute of Psychology, University of Freiburg , Freiburg , Germany.|b School of Psychological Sciences , Monash University Melbourne , Melbourne , Australia.|c Monash-Epworth Rehabilitation Research Centre , Epworth Hospital , Melbourne , Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Schönberger
authors.affiliation: d Department of Medicine, Monash Medical Centre , Monash University Melbourne , Melbourne , Australia.|e Centre for Advanced Imaging , The University of Queensland , St Lucia , Australia.
authors.forename: David
authors.initials: D
authors.lastname: Reutens
authors.affiliation: d Department of Medicine, Monash Medical Centre , Monash University Melbourne , Melbourne , Australia.|f Murdoch Childrens Research Institute, Royal Children's Hospital , Melbourne , Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Beare
authors.affiliation: g Symbion Imaging, Epworth Hospital , Melbourne , Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: O'Sullivan
authors.affiliation: b School of Psychological Sciences , Monash University Melbourne , Melbourne , Australia.
authors.forename: Shantha M W
authors.initials: SMW
authors.lastname: Rajaratnam
authors.affiliation: b School of Psychological Sciences , Monash University Melbourne , Melbourne , Australia.|c Monash-Epworth Rehabilitation Research Centre , Epworth Hospital , Melbourne , Australia.|h National Trauma Research Institute , Melbourne , Australia.
authors.forename: Jennie
authors.identifier: http://orcid.org/0000-0003-0430-125X
authors.initials: J
authors.lastname: Ponsford
mesh_terms: D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000502:physiology*; D000070642:Brain Injuries, Traumatic / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005221:Fatigue / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000473:pathology*; D011597:Psychomotor Performance / Q000502:physiology*; D066127:White Matter / Q000000981:diagnostic imaging / Q000473:pathology*; D055815:Young Adult
keywords: Traumatic brain injury; fatigability; fatigue; magnetic resonance imaging; vigilance