Perceptual Novelty in Tinnitus a Causative Factor for its Persistence. A Stimulus Novelty Based P300 Paradigm on Acute, Chronic, and Non-Tinnitus Controls

Our understanding of tinnitus pathophysiology may be greatly advanced by understanding how the condition evolves from its initial onset or acute stage to its chronic manifestation. Such a transition likely reflects dynamic neurophysiological changes within central auditory and non-auditory networks. Previous studies have highlighted that individuals with acute tinnitus tend to have increased activity in the regions of anterior cingulate cortex, inferior parietal lobe, and insula all of which are essential in constituting the salience network. We therefore aimed at tapping into the salience network of tinnitus through a novelty based P300 paradigm in individuals with Acute, Post Acute (six months follow up since tinnitus onset) Chronic, and Controls. Participants were presented with an auditory oddball paradigm comprising three deviant types: (1) novel environmental sounds, (2) low-frequency tonal deviants, and (3) high-frequency tonal deviants, embedded within a sequence of frequent standard tones. Our results indicate a significant drop in P300 amplitude during the Post Acute stage across the three deviant stimuli, highlighting the substantial influence of the anterior cingulate cortex/salience network in possible generation of tinnitus and inferior parietal lobe in the persistence of tinnitus.