Pathophysiology of Subjective Tinnitus: Triggers and Maintenance.

Haúla Faruk Haider,Agnieszka J Szczepek,Sara F Ribeiro,Tijana Bojić,Deborah A Hall,João Paço

doi:10.3389/fnins.2018.00866

Abstract

Tinnitus is the conscious perception of a sound without a corresponding external acoustic stimulus, usually described as a phantom perception. One of the major challenges for tinnitus research is to understand the pathophysiological mechanisms triggering and maintaining the symptoms, especially for subjective chronic tinnitus. Our objective was to synthesize the published literature in order to provide a comprehensive update on theoretical and experimental advances and to identify further research and clinical directions. We performed literature searches in three electronic databases, complemented by scanning reference lists from relevant reviews in our included records, citation searching of the included articles using Web of Science, and manual searching of the last 6 months of principal otology journals. One-hundred and thirty-two records were included in the review and the information related to peripheral and central mechanisms of tinnitus pathophysiology was collected in order to update on theories and models. A narrative synthesis examined the main themes arising from this information. Tinnitus pathophysiology is complex and multifactorial, involving the auditory and non-auditory systems. Recent theories assume the necessary involvement of extra-auditory brain regions for tinnitus to reach consciousness. Tinnitus engages multiple active dynamic and overlapping networks. We conclude that advancing knowledge concerning the origin and maintenance of specific tinnitus subtypes origin and maintenance mechanisms is of paramount importance for identifying adequate treatment.

Highlights

Tinnitus is a prevalent symptom associated with various conditions and diseases; both otological and non-otological (Baguley et al, 2013)
A major challenge for the field is to identify the underlying causes of subjective chronic tinnitus for developing specific treatments that address the distinct manifestations of tinnitus (Norena, 2015)
Changes in alpha power reflect the enhanced and reduced excitability of engaged neuronal networks (Schlee et al, 2014). These results suggest a role for neural synchrony both for establishing pathological activity within the auditory cortex and for recruiting extra-auditory networks in tinnitus

Summary

Introduction

Tinnitus is a prevalent symptom associated with various conditions and diseases; both otological and non-otological (Baguley et al, 2013). It affects over 70 million people in Europe and more than 50 million people in the United States (Heller, 2003; Henry et al, 2005; Baguley et al, 2013). Tinnitus Pathophysiology for at least 3 to 6 months (i.e., chronic), and their condition has an unknown etiology (i.e., it is subjective). A major challenge for the field is to identify the underlying causes of subjective chronic tinnitus for developing specific treatments that address the distinct manifestations of tinnitus (Norena, 2015). Much research is underway, the precise pathophysiology of tinnitus remains unclear

Objectives

Findings

Conclusion