title: Functional near-infrared spectroscopy to probe state- and trait-like conditions in chronic tinnitus: a proof-of-principle study.
abstract: OBJECTIVE
  Several neuroscience tools showed the involvement of auditory cortex in chronic tinnitus. In this proof-of-principle study we probed the capability of functional near-infrared spectroscopy (fNIRS) for the measurement of brain oxygenation in auditory cortex in dependence from chronic tinnitus and from intervention with transcranial magnetic stimulation.
  
  
  METHODS
  Twenty-three patients received continuous theta burst stimulation over the left primary auditory cortex in a randomized sham-controlled neuronavigated trial (verum = 12; placebo = 11). Before and after treatment, sound-evoked brain oxygenation in temporal areas was measured with fNIRS. Brain oxygenation was measured once in healthy controls (n = 12).
  
  
  RESULTS
  Sound-evoked activity in right temporal areas was increased in the patients in contrast to healthy controls. Left-sided temporal activity under the stimulated area changed over the course of the trial; high baseline oxygenation was reduced and vice versa.
  
  
  CONCLUSIONS
  By demonstrating that rTMS interacts with auditory evoked brain activity, our results confirm earlier electrophysiological findings and indicate the sensitivity of fNIRS for detecting rTMS induced changes in brain activity. Moreover, our findings of trait- and state-related oxygenation changes indicate the potential of fNIRS for the investigation of tinnitus pathophysiology and treatment response.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Regensburg, Universitätsstraße 84, 93053 Regensburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schecklmann
authors.affiliation: Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany.
authors.forename: Anette
authors.initials: A
authors.lastname: Giani
authors.affiliation: Institute of Medical Psychology and Systems Neuroscience, University of Münster, 48149 Münster, Germany.
authors.forename: Sara
authors.initials: S
authors.lastname: Tupak
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Regensburg, Universitätsstraße 84, 93053 Regensburg, Germany.
authors.forename: Berthold
authors.initials: B
authors.lastname: Langguth
authors.affiliation: Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany.
authors.forename: Vincent
authors.identifier: 0000-0003-4722-4805
authors.initials: V
authors.lastname: Raab
authors.affiliation: Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Polak
authors.affiliation: Department of Neurosurgery, University of Würzburg, 97080 Würzburg, Germany.
authors.forename: Csanád
authors.initials: C
authors.lastname: Várallyay
authors.affiliation: Department of Oto-Rhino-Laryngology, Plastic, Aesthetic and Reconstructive Head and Neck Surgery, University of Würzburg, 97080 Würzburg, Germany.
authors.forename: Wilma
authors.initials: W
authors.lastname: Harnisch
authors.affiliation: Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, 97080 Würzburg, Germany.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Herrmann
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tübingen, 72076 Tübingen, Germany.
authors.forename: Andreas J
authors.initials: AJ
authors.lastname: Fallgatter
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000503:physiopathology*; D002908:Chronic Disease; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019265:Spectroscopy, Near-Infrared; D014012:Tinnitus / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation