title: Characterization of thalamo-cortical association using amplitude and connectivity of functional MRI in mild traumatic brain injury.
abstract: OBJECTIVE
  To examine thalamic and cortical injuries using fractional amplitude of low-frequency fluctuations (fALFFs) and functional connectivity MRI (fcMRI) based on resting state (RS) and task-related fMRI in patients with mild traumatic brain injury (MTBI).
  
  
  METHODS
  Twenty-seven patients and 27 age-matched controls were recruited. The 3 Tesla fMRI at RS and finger tapping task were used to assess fALFF and fcMRI patterns. fALFFs were computed with filtering (0.01-0.08 Hz) and scaling after preprocessing. fcMRI was performed using a standard seed-based correlation method, and delayed fcMRI (coherence) in frequency domain were also performed between thalamus and cortex.
  
  
  RESULTS
  In comparison with controls, MTBI patients exhibited significantly decreased fALFFs in the thalamus (and frontal/temporal subsegments) and cortical frontal and temporal lobes; as well as decreased thalamo-thalamo and thalamo-frontal/ thalamo-temporal fcMRI at rest based on RS-fMRI (corrected P < 0.05). This thalamic and cortical disruption also existed at task-related condition in patients.
  
  
  CONCLUSIONS
  The decreased fALFFs (i.e., lower neuronal activity) in the thalamus and its segments provide additional evidence of thalamic injury in patients with MTBI. Our findings of fALFFs and fcMRI changes during motor task and resting state may offer insights into the underlying cause and primary location of disrupted thalamo-cortical networks after MTBI.
authors.affiliation: Department of Radiology / Center for Biomedical Imaging, NYU Langone Medical Center, New York, New York, USA.
authors.forename: Yongxia
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yvonne W
authors.initials: YW
authors.lastname: Lui
authors.forename: Xi-Nian
authors.initials: XN
authors.lastname: Zuo
authors.forename: Michael P
authors.initials: MP
authors.lastname: Milham
authors.forename: Joseph
authors.initials: J
authors.lastname: Reaume
authors.forename: Robert I
authors.initials: RI
authors.lastname: Grossman
authors.forename: Yulin
authors.initials: Y
authors.lastname: Ge
mesh_terms: D000328:Adult; D001930:Brain Injuries / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012146:Rest; D013647:Task Performance and Analysis; D013788:Thalamus / Q000503:physiopathology*
keywords: coherence; fractional amplitude of low frequency fluctuation; functional connectivity (fcMRI); mild traumatic brain injury; resting-state fMRI; thalamus