The Shore Protocol: How Touch + Sound Produces Lasting Tinnitus Relief

Of all the approaches tested in tinnitus research in the past decade, bimodal stimulation — combining sound with precisely-timed somatosensory input — has produced some of the most compelling results. The work of Susan Shore and colleagues at the University of Michigan has shifted how researchers think about where tinnitus is generated and how it can be treated.

The Dorsal Cochlear Nucleus: Where Tinnitus Starts

Most tinnitus research has focused on the auditory cortex, but Susan Shore’s lab at the University of Michigan identified the dorsal cochlear nucleus (DCN) as a critical early site of tinnitus generation. The DCN is a brainstem structure that receives input from two very different sources: the cochlea (auditory input from the ear) and the somatosensory system (touch, proprioception, and jaw/neck movement).

This dual input explains a well-known clinical observation: many tinnitus patients can modulate their tinnitus by moving their jaw, pressing on their neck, or making facial expressions. This “somatic modulation” of tinnitus, present in roughly 65–80% of tinnitus patients (Shore et al., 2016), is a direct expression of somatosensory inputs reaching the DCN and altering its output.

In tinnitus, the DCN shows pathological hyperactivity: it fires spontaneously and with enhanced synchrony at the tinnitus frequency, even without cochlear input. Shore’s hypothesis was that deliberately applying somatosensory input at a precise time relative to auditory input could reverse this hyperactivity through synaptic plasticity mechanisms.

What Bimodal Stimulation Is

Bimodal stimulation delivers two inputs simultaneously:

• Auditory: A broadband noise, tone, or click at or near the tinnitus frequency
• Somatosensory: A brief tactile or electrical stimulus to the jaw, cheek, neck, or shoulder

The crucial element is the timing relationship between the two signals. The somatosensory stimulus is delivered a fixed interval before (or occasionally after) the auditory stimulus. In Shore’s clinical implementation, the tactile stimulus precedes the sound by approximately 20 milliseconds.

Why 20 ms Matters: The Hebbian Plasticity Window

The 20 ms window is not arbitrary. It is determined by the timing rules of synaptic plasticity in the DCN. Specifically, it exploits spike-timing-dependent plasticity (STDP): the principle that synaptic connections are strengthened when a presynaptic neuron fires just before a postsynaptic neuron, and weakened when the order is reversed.

At the DCN, somatosensory inputs synapse onto the same neurons that receive cochlear input. When the somatosensory signal arrives 20 ms before the auditory signal, it fires the DCN neuron just before the auditory input arrives — placing it in the STDP window for depression of the somatosensory synapse. This selectively reduces the drive to the hyperactive DCN neurons, progressively quieting the spontaneous firing that generates tinnitus.

When the somatosensory stimulus is delivered after the auditory signal (or at zero offset), the effect reverses — synaptic potentiation occurs, and tinnitus can actually worsen. This is why the precise timing is not merely a technical detail but is central to therapeutic safety.

The Shore et al. Clinical Trials

The landmark bimodal stimulation trials were published in Science Translational Medicine (2018) and expanded in subsequent papers.

2018 trial (n=20)

In the initial crossover RCT, Shore et al. tested bimodal stimulation (sound + precisely-timed jaw stimulation) against sham (sound alone) in 20 participants. The key findings:

• 60% of participants showed clinically meaningful reduction in tinnitus loudness (measured in dB) in the bimodal condition
• Average tinnitus loudness reduction: approximately 12 dB in responders
• The effect was sustained for up to 4 weeks after the treatment period ended
• The response was frequency-specific — only the treated frequency showed reduced neural activity on imaging, confirming the proposed mechanism
• No significant adverse effects were observed

2022 expanded trial (n=99)

The larger follow-up trial, published in Science Translational Medicine (2022), with 99 participants confirmed:

• Statistically significant improvement in Tinnitus Handicap Inventory scores
• Durable effects in the majority of responders
• Individuals with somatic modulation (those who can already modulate their tinnitus with jaw movement) showed the strongest response

Who Is Most Likely to Benefit

Based on the trial data and subsequent observational studies, bimodal stimulation is most likely to help individuals who:

• Can modulate their tinnitus somatically — i.e., making a jaw movement or pressing the neck changes the tinnitus pitch or loudness, even temporarily
• Have unilateral or asymmetric tinnitus (the protocol’s frequency targeting is most precise for single-pitch presentations)
• Have recent-onset tinnitus (within 5 years) — longer-standing tinnitus has more established neural pathways that are harder to modify
• Can accurately identify their tinnitus pitch for frequency calibration

Using Bimodal Stimulation in Tinnitus Wizard

Tinnitus Wizard implements bimodal stimulation using the clenching/tapping protocol, where you provide the somatosensory component manually (a gentle jaw clench or shoulder tap) precisely timed relative to sound pulses delivered through headphones.

1. Complete Foundation and ACRN sessions first (Weeks 1–4). Bimodal stimulation unlocks at Week 5.
2. Set your tinnitus frequency accurately before each bimodal session — frequency accuracy is even more critical here than for notched noise.
3. Use the clenching/tapping guide. The app will prompt you with a visual cue; perform a gentle jaw clench or shoulder touch when prompted, approximately 20 ms before each auditory pulse (the app handles the timing).
4. Touch targets are large (48px minimum) for comfortable in-session use on mobile.
5. Sessions of 30–45 minutes are typical in clinical protocols. Longer sessions may cause jaw fatigue.

Practical Notes for Home Use

• Use over-ear headphones (not earbuds) for consistent sound delivery and precise timing.
• Jaw fatigue is normal in early sessions. Take breaks if needed — the therapeutic effect is dose-dependent but not harmed by pausing within a session.
• Do not apply strong pressure to the jaw or neck. The somatosensory input should be a gentle, consistent touch — not forceful pressure.
• Measure regularly: the Residual Inhibition test in Tinnitus Wizard can track whether your DCN responsiveness is changing over weeks.
• Bimodal stimulation can be combined with notched noise on alternating days, or in separate session blocks.