A Brief History of S-Tones
In 2006, researchers at UCI began working with a patient with a cochlear implant who was suffering from tinnitus. Traditional stimulation approaches were attempted, but failed to provide relief. A low frequency electric stimulus was presented via the cochlear implant.
"During the first 150 seconds of this low-rate stimulus, nothing happened as the subject perceived both the stimulus and his tinnitus. Surprisingly at the 180 seconds mark, the subject, for the first time in two years, could not hear any of the high-pitched tinnitus. All he heard was a calming, pleasant tone produced by the low-rate stimulus."
This discovery led to the creation of S-Tones, the foundation of the SoundCure Serenade technology.
Temporally Patterned Sounds and the Auditory Cortex
Research has shown that S-Tones can produce synchronized, robust neural activity in the auditory cortex. Figure 1 shows that sounds that are too slow produce bursts of activity and those that are too fast show no synchronization, but within a specific range the neurons fire synchronously to the sound stimulus.
S-Tones in Action
Studies by researchers suggest that the use of S-Tones may play a role in promoting tinnitus suppression. According to a UCI researcher, “The mechanisms underlying tinnitus suppression are different from those in tinnitus masking. Masking attempts to divert a patient’s attention away from the tinnitus. Suppression is a physiologic process where sounds—in this case, patterned sounds—may likely be modulating the activity of the auditory cortex and interrupting tinnitus generation.”
Further, synchronized neural activity is described this way in a research paper, with a sample S-Tone effect: "Within 30 seconds, the subject started to experience some tinnitus suppression and by 120 seconds reported being unable to hear his tinnitus. This is an example of 100% suppression."
S-Tones do not need to be loud to be effective, researchers have discovered: "…A sound is presented that is softer than the level of the tinnitus, which may completely eliminate the perception of the tinnitus. The overall level of the sound environment is less than the tinnitus alone.”
Research is ongoing and the treatment sounds continue to be studied.
Our Sound Therapy Suite
S-Tones represent an exciting sound therapy. However, tinnitus is not a simple condition that can be addressed with a one-size-fits-all approach. SoundCure believes that a heterogeneous condition like tinnitus needs a flexible, customized approach. Therefore SoundCure offers customized S-Tones, and other sound therapy tracks, which include customized narrowband stimuli that have been used extensively in the tinnitus clinic at the UC Irvine as well as broadband sound that has brought relief to patients for decades.
2. Figure adapted from: Liang et al., Neural Representations of Sinusoidal Amplitude and Frequency Modulations in the Primary Auditory Cortex of Awake Primates. J Neurophysiol. 2002; 87:2237-2261.