title: Design and evaluation of tinnitus synthesis methods: from spectral to spatial matching.
abstract: OBJECTIVE
  This study was designed to investigate methods to help patients suffering from unilateral tinnitus synthesizing an auditory replica of their tinnitus.
  
  
  METHODS
  Two semi-automatic methods (A and B) derived from the auditory threshold of the patient and a method (C) combining a pure tone and a narrow band-pass noise centred on an adjustable frequency were devised and rated on their likeness over two test sessions. A third test evaluated the stability over time of the synthesized tinnitus replica built with method C, and its proneness to merge with the patient's tinnitus. Patients were then asked to try and control the lateralisation of this single percept through the adjustment of the tinnitus replica level.
  
  
  RESULTS
  The first two tests showed that seven out of ten patients chose the tinnitus replica built with method C as their preferred one. The third test, performed on twelve patients, revealed pitch tuning was rather stable over a week interval. It showed that eight patients were able to consistently match the central frequency of the synthesized tinnitus (presented to the contralateral ear) to their own tinnitus, which leaded to a unique tinnitus percept. The lateralisation displacement was consistent across patients and revealed an average range of 29dB to obtain a full lateral shift from the ipsilateral to the contralateral side.
  
  
  CONCLUSIONS
  Although spectrally simpler than the semi-automatic methods, method C could replicate patients' tinnitus, to some extent. When a unique percept between synthesized tinnitus and patients' tinnitus arose, lateralisation of this percept was achieved.
authors.affiliation: UMR 9912 - Sciences et Techniques de la Musique et du Son - IRCAM-CNRS-UPMC, France; Sonic Arts Research Centre, Queen's University Belfast, United Kingdom. s.bertet@qub.ac.uk
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Bertet
authors.forename: Alexis
authors.initials: A
authors.lastname: Baskind
authors.forename: Alain
authors.initials: A
authors.lastname: Londero
authors.forename: Laure
authors.initials: L
authors.lastname: Bonfils
authors.forename: Isabelle
authors.initials: I
authors.lastname: Viaud-Delmon
authors.forename: Olivier
authors.initials: O
authors.lastname: Warusfel
mesh_terms: D000328:Adult; D001309:Auditory Threshold; D003198:Computer Simulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010897:Pitch Discrimination; D014012:Tinnitus / Q000628:therapy*