Looking for objective correlates between tinnitus and cochlear synaptopathy


  • Chiara Casolani Hearing Systems Section, Department of Health Technology, Technical University of Denmark, DK-2800 Lyngby, Denmark
  • James Michael Harte Interacoustics Research Unit, part of Oticon A/S, DK-2800 Lyngby, Denmark
  • Bastian Epp Hearing Systems Section, Department of Health Technology, Technical University of Denmark, DK-2800 Lyngby, Denmark


Tinnitus is the perception of a sound in the absence of acoustic stimulation. While usually connected to a hearing loss, there exists a subset of tinnitus sufferers with audiologically normal hearing, whose tinnitus was often initiated by a noise trauma. Noise-induced tinnitus might be connected to the noise exposure that leads to a permanent impairment of the hearing system without affecting sensitivity to sound. This is commonly referred to as hidden hearing loss (HHL) and might be connected to cochlear synaptopathy. The hypothesis that HHL is one of the causes underlying tinnitus is based on suppositions that both phenomena are related to deafferentation of auditory nerve fibres and related central gain adjustments. To investigate this connection, a screening procedure consisting of high frequency audiometry (HFA), tinnitus likeness spectrum and loudness, psychophysical tuning curves (PTC) and tinnitus masking curves (TMC), adaptive categorical loudness scaling, and middle-ear muscle reflex test was developed. Pilot results show that all measurements can be completed within a short time frame, due to a Bayesian procedure being adopted to measure HFA, PTC and TMC. These procedures may contribute to investigating the connection between tinnitus and HHL with a large number of outcome measures. This connection will provide important insights toward the development of better diagnoses and treatment methods.


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How to Cite

Casolani, C., Harte, J. M., & Epp, B. (2020). Looking for objective correlates between tinnitus and cochlear synaptopathy. Proceedings of the International Symposium on Auditory and Audiological Research, 7, 421–428. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2019-49



2019/5. Other topics in auditory and audiological research