Deep Brain Stimulation Reduces Tinnitus in Rats

A new study demonstrates that directly stimulating the brain’s reward center can reduce tinnitus perception in rats by reconditioning maladaptive neural circuits. The research, published in *Scientific Reports*, provides a potential new direction for treating disorders rooted in faulty learning.

Targeting the Brain’s Salience Network

Many chronic conditions, including tinnitus, misophonia, and some psychiatric disorders, may originate from maladaptive conditioning. The brain learns to assign excessive importance to a neutral or internal signal. The neural system responsible for this valuation is the salience network. It governs reward, motivation, and habit formation. Researchers Yiwen Zheng, Renelyn Sistoza Parra, and Jonny Park hypothesized that directly modulating the core of this network—the ventral striatum, and specifically the nucleus accumbens—could change how the brain perceives tinnitus.

Their work builds on a growing understanding of central brain networks in hearing disorders. For example, separate fMRI research has been mapping brain responses in conditions like hyperacusis, and other studies explore the cerebellum’s role in auditory processing.

Method: Rewarding and Dysrewarding Stimulation in Rats

The team used a validated rat model of tinnitus. They then implanted tiny electrodes to deliver precise electrical stimulation to specific brain areas. The primary target was the nucleus accumbens (NAc (NAC supplement)), a hub for processing reward. A second target was the lateral habenula (LHb), a region associated with negative outcomes and disappointment.

Rats were divided into groups receiving different stimulation protocols. One group received rewarding NAc stimulation only when paired with external tones that did not match their tinnitus frequency. Another group received a combined protocol: rewarding NAc stimulation with non-tinnitus tones, and dysrewarding LHb stimulation paired with tones that matched their tinnitus frequency. The goal was to teach the brain to devalue the tinnitus signal and value other sounds.

Rewarding Stimulation Alone Was Most Effective

The results were clear. Bilateral rewarding stimulation of the nucleus accumbens, carefully timed with non-tinnitus tones, produced the most effective suppression of tinnitus perception. Behavioral tests showed the rats no longer reacted as if they were hearing a constant phantom sound.

The combined approach—using both rewarding and dysrewarding stimulation—also suppressed tinnitus. However, it came with a significant drawback: observable negative behavioral effects, likely reflecting the aversive nature of stimulating the lateral habenula. This suggests that while suppressing a maladaptive signal is possible, inducing a negative state is not a viable therapeutic path.

How Reconditioning Works

The mechanism is a form of neural re-learning. By consistently pairing a rewarding sensation (from NAc stimulation) with the presence of real, external non-tinnitus tones, the brain’s salience network is retrained. The network learns to shift its attention and value away from the internal tinnitus frequency and toward the external world. The tinnitus signal loses its “importance” and is effectively filtered out. This is a direct intervention in the learning circuit, unlike approaches that target the auditory periphery or general arousal.

Practical Implications and Future Directions

This study provides a proof-of-concept for a novel treatment strategy. It moves beyond managing symptoms and aims to correct the faulty learning at the root of the problem. For humans, this could eventually translate to refined deep brain stimulation techniques or the development of drugs that can selectively modulate the salience network’s activity.

The authors note their reconditioning strategy could apply to other disorders rooted in maladaptive conditioning. This includes certain fear-based anxieties, addiction, and potentially components of misophonia, where specific sounds trigger disproportionate distress. The brain response patterns in misophonia also point to atypical salience network processing, making it a candidate for such an approach.

Crucially, the finding that pure reward-based conditioning worked best is encouraging. It suggests future therapies might focus on promoting positive neural plasticity rather than suppressing signals with punishment. This aligns with behavioral approaches like tinnitus retraining therapy, which combines sound enrichment with counseling.

Source: Zheng, Y., Parra, R.S., & Park, J. Rewarding stimulation of the nucleus accumbens reconditions the salience network and suppresses tinnitus in a rat model. Sci Rep (2025). https://doi.org/10.1038/s41598-026-49513-z