Tinnitus masker sensation level (SL), is how much louder the tinnitus is above the ambient noise of the environment. By raising the ambient level of noise (playing white noise into the ear), the apparent loudness of tinnitus is reduced. The noise level is close to and usually somewhat louder than the perceived loudness of the tinnitus. The generated noise is designed to be a calming, less intrusive sound than the ringing or hissing of tinnitus. Depending on the loudness of the noise, tinnitus may be fully or partially masked. Tinnitus masking cannot reduce or eliminate tinnitus, only reduce awareness of it. The
Tinnitus retraining therapy with tinnitus have a comorbid psychological injury or illness (e.g., post-traumatic stress disorder, depression, anxiety, obsessive compulsive disorder, stress, dysfunction of the temporomandibular joint, etc.) that can exacerbate the tinnitus. It has been proposed that tinnitus is caused by mechanisms that generate abnormal neural activity, specifically one mechanism called discordant damage (dysfunction) of outer and inner hair cells of the cochlea. The psychological basis for TRT stems from the fact that the brain exhibits a high level of plasticity. In turn, this allows it to adjust to any sensory signals as long as they do not lead to negative effects.