Clinical neuroscienceThe development and test-retest reliability of a method for matching perceived location of tinnitus

- A new tinnitus assessment method that includes the localization of tinnitus is described.
- Two studies were undertaken to validate the method and showed it to be a good match to self-reported location.
- The method could be incorporated into clinical and research assessment of tinnitus, including development of stimuli for imaging and electrophysiology.

BackgroundA software-based method for assessing and tinnitus in three-dimensional (3D) 'virtual' auditory space is described and tested.New methodPhase I was a proof-of-concept evaluation of tinnitus localization in the horizontal plane in 19 participants. Phase II assessed the reliability of software developed from phase I findings in 34 participants. The software used interaural timing and level differences and an average Head Related Transfer Function (HRTF) to match tinnitus in the horizontal and vertical plane. The reliability of the localization method was assessed across two sessions at least 1 week apart and compared to the test-retest repeatability of pitch and loudness matching using both the new assessment software and a traditional audiometer-based method. The validity of the method was compared to participants' verbal self-reports of tinnitus and their handwritten markings of tinnitus position on an image of a head.ResultsParticipants could localize sound to a position in or around the head that was a good match to their self-report of location.Comparison with existing method(s)The method showed test-retest reliability (intraclass correlation: azimuth 0.78; elevation 0.37) comparable to matching other tinnitus attributes (intraclass correlation: pitch 0.73; loudness 0.48).ConclusionsTinnitus has a spatial attribute that can be more precisely described than “at the ear(s)” or “in the head”. The method has important ramifications for the assessment and management of tinnitus that make use of the spatial representation of sound.