title: Controversy: Does repetitive transcranial magnetic stimulation/ transcranial direct current stimulation show efficacy in treating tinnitus patients?
abstract: BACKGROUND
  Tinnitus affects 10% of the population, its pathophysiology remains incompletely understood, and treatment is elusive. Functional imaging has demonstrated a relationship between the intensity of tinnitus and the degree of reorganization in the auditory cortex. Experimental studies have further shown that tinnitus is associated with synchronized hyperactivity in the auditory cortex. Therefore, targeted modulation of auditory cortex has been proposed as a new therapeutic approach for chronic tinnitus.
  
  
  METHODS
  Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are noninvasive methods that can modulate cortical activity. These techniques have been applied in different ways in patients with chronic tinnitus. Single sessions of high-frequency rTMS over the temporal cortex have been successful in reducing the intensity of tinnitus during the time of stimulation and could be predictive for treatment outcome of chronic epidural stimulation using implanted electrodes.
  
  
  RESULTS
  Another approach that uses rTMS as a treatment for tinnitus is application of low-frequency rTMS in repeated sessions, to induce a lasting change of neuronal activity in the auditory cortex beyond the duration of stimulation. Beneficial effects of this treatment have been consistently demonstrated in several small controlled studies. However, results are characterized by high interindividual variability and only a moderate decrease of the tinnitus. The role of patient-related (for example, hearing loss, tinnitus duration, age) and stimulation-related (for example, stimulation site, stimulation protocols) factors still remains to be elucidated.
  
  
  CONCLUSIONS
  Even in this early stage of investigation, there is a convincing body of evidence that rTMS represents a promising tool for pathophysiological assessment and therapeutic management of tinnitus. Further development of this technique will depend on a more detailed understanding of the neurobiological effects mediating the benefit of TMS on tinnitus perception. Moreover clinical studies with larger sample sizes and longer follow-up periods are needed.
authors.affiliation: Department of Psychiatry, University of Regensburg, Germany. Berthold.Langguth@medbo.de
authors.forename: Berthold
authors.initials: B
authors.lastname: Langguth
authors.forename: Dirk
authors.initials: D
authors.lastname: de Ridder
authors.forename: John L
authors.initials: JL
authors.lastname: Dornhoffer
authors.forename: Peter
authors.initials: P
authors.lastname: Eichhammer
authors.forename: Robert L
authors.initials: RL
authors.lastname: Folmer
authors.forename: Elmar
authors.initials: E
authors.lastname: Frank
authors.forename: Felipe
authors.initials: F
authors.lastname: Fregni
authors.forename: Christian
authors.initials: C
authors.lastname: Gerloff
authors.forename: Eman
authors.initials: E
authors.lastname: Khedr
authors.forename: Tobias
authors.initials: T
authors.lastname: Kleinjung
authors.forename: Michael
authors.initials: M
authors.lastname: Landgrebe
authors.forename: Scott
authors.initials: S
authors.lastname: Lee
authors.forename: Jean-Pascal
authors.initials: JP
authors.lastname: Lefaucheur
authors.forename: Alain
authors.initials: A
authors.lastname: Londero
authors.forename: Renata
authors.initials: R
authors.lastname: Marcondes
authors.forename: Aage R
authors.initials: AR
authors.lastname: Moller
authors.forename: Alvaro
authors.initials: A
authors.lastname: Pascual-Leone
authors.forename: Christian
authors.initials: C
authors.lastname: Plewnia
authors.forename: Simone
authors.initials: S
authors.lastname: Rossi
authors.forename: Tanit
authors.initials: T
authors.lastname: Sanchez
authors.forename: Philipp
authors.initials: P
authors.lastname: Sand
authors.forename: Winfried
authors.initials: W
authors.lastname: Schlee
authors.forename: Dipl
authors.initials: D
authors.lastname: Pysch
authors.forename: Thomas
authors.initials: T
authors.lastname: Steffens
authors.forename: Paul
authors.initials: P
authors.lastname: van de Heyning
authors.forename: Goeran
authors.initials: G
authors.lastname: Hajak
mesh_terms: D000328:Adult; D006801:Humans; D011795:Surveys and Questionnaires; D014012:Tinnitus / Q000628:therapy*; D050781:Transcranial Magnetic Stimulation / Q000295:instrumentation / Q000379:methods*; D004561:Transcutaneous Electric Nerve Stimulation / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome