A consideration of the effect of ear canal resonance and hearing loss upon white noise generators for tinnitus retraining therapy.

Tinnitus retraining therapy has been heralded as a major advance in the alleviation of tinnitus perception. A cornerstone of this technique is to use white noise produced by a white noise generator (WNG) over a period of several months in order to assist the patient to habituate to their tinnitus. There are three factors which influence the frequency spectrum of the perceived noise such that the perception of white noise from a WNG is unlikely. These factors are the actual spectrum of the emitted noise, the ear canal resonance of the patient and the hearing sensitivity of the patient. Advocates of tinnitus retraining therapy state that white noise is the optimal stimulation to assist habituation of tinnitus. This paper demonstrates that this optimal situation is unlikely to be achieved and that this may account for the long periods needed for patients to achieve benefit from the technique. The development of devices that allow for the above factors to be countered is suggested.