Cognitive tinnitus sensitization: Behavioral and neurophysiological aspects of tinnitus centralization

OBJECTIVE: Acquired centralized tinnitus (ACT) is the most frequent type of chronic tinnitus. We introduce a cognitive neurophysiological ACT hypothesis based on centralized cognitive sensitization processes. MATERIAL AND METHODS: Published cognitive sensitization processes were reviewed using PubMed. Furthermore, a Cochrane analysis was performed. RESULTS: Patients frequently perceive tinnitus as being extremely loud although audiological tinnitus-matching measures reveal that its loudness levels are low. An important principle of central tinnitus processing is that individual tinnitus appraisal is directly linked to neuronal networks in the brain responsible for the production of emotions and cognitions. Cognitive processes may be associated with a reduction in the tinnitus cognition threshold, resulting in hypersensitivity of cognition. The underlying mechanism is known as sensitization and is suggested to be a specific learning process. CONCLUSIONS: ACT may be associated with a specific learning process allowing increased tinnitus awareness and continuous appraisal. The underlying mechanism, the cognitive tinnitus sensitization process, is associated with a decrease in the tinnitus cognition threshold. The sensitization contributes to the extremely loud cognition of the tinnitus signal. The associated audiological cognitive discrepancy can be used clinically and diagnostically to identify patients for cognitive testing. The sensitization model does not require tinnitus hyperactivity.