The field of tinnitus treatment has seen growing interest in the role of neuromodulation techniques over recent years:

Over recent years, the field of tinnitus treatment has seen growing interest in the role of neuromodulation techniques. Neuromodulation refers to the process of altering nerve activity through targeted delivery of a stimulus, and it encompasses various methods, including transcranial direct current stimulation (tDCS), transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS), and combination therapies. This synthesis provides an overview of recent developments in neuromodulation for treating tinnitus, supported by current literature.

Recent systematic reviews and clinical studies have highlighted the therapeutic potential of neuromodulation. Hoare et al. conducted a systematic review that assessed different neuromodulation treatments targeting pathological synchrony, demonstrating varying levels of success in alleviating tinnitus symptoms (Hoare et al., 2024). Heiland et al. elaborated on this by presenting a meta-analysis that substantiates the renewed interest in neuromodulation, particularly following the FDA's 2023 approval of a neuromodulation device dedicated to tinnitus treatment (Heiland et al., 2024). These foundational studies indicate a shift in clinical practice towards incorporating neuromodulation techniques, supported by a solid base of evidence.

One noteworthy advancement is bimodal stimulation, which combines acoustic and electrical stimuli. Conlon et al. found that this approach significantly reduces tinnitus symptoms and suggests that the simultaneous application of auditory and electrical stimuli optimizes therapeutic outcomes (Conlon et al., 2020). Animal studies further support this by showing that bimodal stimulation can desynchronize neural circuits responsible for tinnitus perception (Chen et al., 2023). Furthermore, Shin et al. reported efficacy in combining various treatment modalities, indicating that less invasive and milder stimulation methods effectively reduce tinnitus distress (Shin et al., 2023). Such findings underline the growing acceptance of bimodal neuromodulation as a viable treatment pathway.

Vagus nerve stimulation (VNS) has been identified as particularly promising in tinnitus treatment. Research by Yakunina and Nam shows that VNS paired with auditory stimuli enhances neuroplastic changes in the auditory cortex, potentially leading to symptom relief (Yakunina & Nam, 2021). This is corroborated by newer meta-analyses that confirmed VNS's beneficial effects on tinnitus, demonstrating its ability to modulate brain circuitry governing auditory processing and experience (Fernández-Hernando et al., 2023). The success of this method opens avenues for exploring its combination with other neuromodulatory techniques for potentially greater efficacy.

In contrast, approaches relying solely on tDCS have produced mixed results, with some studies suggesting that optimal parameters for the modality must be thoroughly established for maximum therapeutic benefit (Shekhawat & Vanneste, 2018). Recent trials have explored various configurations of tDCS, including targeting the dorsolateral prefrontal cortex and varying current intensities, which have shown promise in modulating tinnitus loudness and distress levels (Yadollahpour et al., 2024). Future research must address these optimization challenges to refine tDCS applications in tinnitus treatment further.

In conclusion, the literature indicates a significant shift towards utilizing neuromodulation therapies in tinnitus management. Bimodal stimulation and VNS emerge as particularly effective options, while traditional tDCS approaches require refinement of techniques and protocols. Integrating these modalities into clinical practice can enhance treatment outcomes for individuals suffering from tinnitus, underscoring the importance of ongoing research in this innovative field.

Edvaldo de Oliveira Leme

References:

Chen, S., Du, M., Wang, Y., Li, Y., Tong, B., Qiu, J., … & Liu, Y. (2023). State of the art: non-invasive electrical stimulation for treating chronic tinnitus. Therapeutic Advances in Chronic Disease, 14. https://doi.org/10.1177/20406223221148061

Conlon, B., Langguth, B., Hamilton, C., Hughes, S., Meade, E., Connor, C., … & Lim, H. (2020). In a large randomized clinical study, bimodal neuromodulation combining sound and tongue stimulation reduces tinnitus symptoms. Science Translational Medicine, 12(564). https://doi.org/10.1126/scitranslmed.abb2830

Fernández-Hernando, D., Fernández‐de‐las‐Peñas, C., Machado-Martín, A., Angulo, S., García-Esteo, F., & Mesa-Jiménez, J. (2023). Effects of non-invasive neuromodulation of the vagus nerve for management of tinnitus: a systematic review with meta-analysis. Journal of Clinical Medicine, 12(11), 3673. https://doi.org/10.3390/jcm12113673