Tinnitus, a persistent ringing or buzzing in the ears, affects millions of people worldwide.
A new study tested a combination therapy of trigeminal nerve stimulation and tailored sound therapy that shows promise for reducing tinnitus symptoms and improving quality of life.
Key facts:
- Tinnitus affects approximately 10% of adults, with 2.4% experiencing severe effects on quality of life. There is no cure.
- The study tested transcutaneous trigeminal nerve stimulation (TTNS) combined with notched sound therapy (NST).
- 14 patients used the therapies together for 30 mins/day, 5 days/week for 4 weeks.
- Results showed improvements in tinnitus severity, sleep, depression, and quality of life.
- The therapies are non-invasive and safe. More research is needed.
Source: Yonsei Medical Journal Oct 2023
What is tinnitus?
Tinnitus is the perception of sound when no external sound source is present. Patients describe it as ringing, buzzing, roaring, clicking or hissing in one or both ears. It can be constant or intermittent.
Tinnitus affects about 10% of adults, with severity ranging from mild to debilitating.
An estimated 2.4% of adults have tinnitus so severe that it substantially reduces their quality of life.
It leads to anxiety, depression, sleep problems, trouble concentrating, and overall poorer health.
There is no cure for chronic tinnitus. Current therapies aim to make it less intrusive and manage symptoms.
Options include hearing aids, sound therapy, relaxation techniques, cognitive behavioral therapy, and medications.
Results are mixed. New and better therapies are needed.
What causes tinnitus?
In most cases, tinnitus is linked to some degree of hearing loss, often noise-induced or age-related.
Hearing loss causes changes in nerve signaling in auditory pathways to the brain.
Even with hearing loss, the auditory nerves and brain continue generating spontaneous activity, but without external sound input. Tinnitus may arise from this altered signaling.
There are other causes like ear infections, head/neck injuries, circulatory system disorders, and side effects of some medications. Often the exact cause is unknown.
Several brain structures are involved in processing sound and may contribute to tinnitus when damaged or deprived of input.
The dorsal cochlear nucleus, part of the brainstem, integrates auditory and somatosensory signals.
Disrupted input to this region may trigger central auditory pathways to generate tinnitus perceptions.
Cortical regions like the auditory cortex also show elevated spontaneous activity in tinnitus patients.
Testing trigeminal nerve stimulation for tinnitus
The trigeminal nerve conveys sensations from the face to the brainstem and has connections with auditory processing regions like the dorsal cochlear nucleus.
Previous research suggests that somatosensory input from the trigeminal nerve can inhibit auditory signaling, including tinnitus perceptions.
Transcutaneous trigeminal nerve stimulation (TTNS) aims to activate this inhibitory pathway non-invasively by attaching electrodes to the skin surface over the trigeminal nerve on the face.
Small amounts of electrical current stimulate the nerve.
This study tested TTNS combined with sound therapy in 14 patients with chronic tinnitus.
Sound therapy aims to reverse maladaptive auditory pathway changes and was tailored by removing frequencies matching each patient’s specific tinnitus pitch – this is called notched sound therapy (NST).
Study design
Participants:
- 14 adults with chronic tinnitus (over 3 months)
- Average age 49 years old
- 9 men, 5 women
Procedure:
- Visits at start and after 4 weeks of treatment
- Used TTNS + NST together for 30 mins/day, at least 5 days/week for 4 weeks
- Recorded symptoms, sleep, mood, and quality of life before and after treatment using surveys
TTNS:
- Electrode placed on skin overlying trigeminal nerve on face
- 30 Hz electrical pulses at 4-7 mA intensity
NST:
- Custom sound files removing tinnitus frequencies
- Listened on mobile devices with headphones
Results of TTNS & NST combination treatment
After 4 weeks of combined TTNS + NST:
- Tinnitus severity decreased, based on tinnitus surveys
- Improved sleep quality, measured by standardized sleep survey
- Reduced depressive symptoms
- Increased quality of life scores
In addition:
- Brain wave patterns changed – increased low beta waves, linked to concentration
- Autonomic nervous system balance improved
- Lowered physiological stress markers
These changes suggest the therapy decreased tinnitus impact and improved nervous system function.
Possible advantages of the combination treatment
This study provides evidence that simple, non-invasive electrical trigeminal nerve stimulation, when combined with customized sound therapy, may improve debilitating tinnitus symptoms.
Benefits include:
- Uses portable device patients self-administer at home
- Does not require taking medication
- Reduced tinnitus severity, especially tinnitus catastrophizing
- Improved ability to concentrate
- Less depression and anxiety
- Better sleep
- Higher overall quality of life
This therapy was safe and well-tolerated with minimal side effects.
It takes advantage of trigeminal-auditory connections to reduce aberrant activity driving tinnitus perceptions.
Combining sound therapy promotes helpful long-term changes in auditory processing.
Both therapies change nervous system activity in ways that make the brain generate less bothersome tinnitus signals.
Together they provided robust improvements in a small number of patients.
Future directions in tinnitus treatment
While promising, more research is needed to confirm benefits of trigeminal nerve stimulation for tinnitus. Next steps include:
- Larger clinical trials with more patients and control groups
- Comparing effects of each therapy alone vs. in combination
- Determining optimal stimulation parameters
- Long-term follow-up on durability of improvements
- Evaluating brain changes with neuroimaging
- Understanding individual differences in responsiveness
With further testing, this non-invasive nerve stimulation could become part of standard tinnitus treatment. It has potential to improve outcomes when combined with other therapies like hearing aids or cognitive behavioral therapy.
Final thoughts on trigeminal nerve stimulation for tinnitus
For those severely affected by tinnitus, a safe non-invasive therapy with lasting effects would dramatically improve quality of life.
This early study suggests trigeminal nerve stimulation, when combined with sound therapy tailored to a patient’s specific tinnitus frequency, may retrain the brain to reduce distressing tinnitus perceptions.
Larger scale clinical trials are underway.
With refinement, trigeminal nerve stimulation could become an effective new option for reducing tinnitus impact on millions of sufferers worldwide.
References
- Study: Effects of Transcutaneous Trigeminal Electrical Stimulation & Sound Therapy in Patients with Tinnitus
- Authors: Young Sang Cho et al. (2023)
