title: Abnormal whole-brain functional networks in homogeneous acute mild traumatic brain injury.
abstract: OBJECTIVE
  To evaluate the whole-brain resting-state networks in a homogeneous group of patients with acute mild traumatic brain injury (MTBI) and to identify alterations in functional connectivity induced by MTBI.
  
  
  METHODS
  Thirty-five patients with acute MTBI and 35 healthy control subjects, matched in age, gender, handedness, and education, underwent resting-state fMRI, susceptibility weighted imaging, neuropsychological, and postconcussive symptom assessments. We ensured the homogeneity of the patient group by limiting the injury mechanism to fronto-occipital impacts. Alterations in functional connectivity were analyzed by using data-driven independent component analysis, which is not biased by a priori region selection.
  
  
  RESULTS
  We found a decrease in functional connectivity within the motor-striatal network in the MTBI group. At the same time, patients showed deficits in psychomotor speed as well as in speed of information processing. We propose that although disorders in motor function after MTBI are rarely reported, injury still has an effect on motor functioning, which in its turn may also explain the reduction in speed of information processing. Further, we found a cluster of increased functional connectivity in the right frontoparietal network in the MTBI group. We suggest that this abnormal increased connectivity might reflect increased awareness to external environment and explain excessive cognitive fatigue reported by patients with MTBI. It might also underlie the physical postconcussive symptoms, such as headache and increased sensitivity to noise/light.
  
  
  CONCLUSIONS
  We proved that whole-brain functional connectivity is altered early (within 4 weeks) after MTBI, suggesting that changes in functional networks underlie the cognitive deficits and postconcussive complaints reported by patients with MTBI.
authors: Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Radboud University Nijmegen, The Netherlands. elena.shumskaya@donders.ru.nl
authors: Elena
authors: E
authors: Shumskaya
authors: Teuntje M J C
authors: TM
authors: Andriessen
authors: David G
authors: DG
authors: Norris
authors: Pieter E
authors: PE
authors: Vos
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001924:Brain Concussion / Q000175:diagnosis; D001930:Brain Injuries / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000503:physiopathology*; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000503:physiopathology; D015599:Trauma Severity Indices; D055815:Young Adult