A clinical trial has shown that a therapy called Acoustic Coordinated Reset (ACR) can reduce the loudness and annoyance caused by tinnitus in seven out of ten patients. The clinical trial compared Acoustic Coordinated Reset (ACR) against a control treatment in 63 people with long term tinnitus.
In the clinical trial, patients were required to wear special headphones for a few hours each day. The headphones emit a series of tones tuned according to the characteristic frequency of the patient's tinnitus. This is said to disrupt the rhythmic firing patterns of tinnitus-creating auditory nerve cells.
Tinnitus became quieter and less annoying
The volunteers were first asked to match their tinnitus tone to one of a range played to them.
Scientists found that playing sufferers the same tone which they â€œhearâ€ in their mind stops the auditory brain cells from creating the perceived noise. The tone was played to the volunteers through in-ear headphones for four to six hours a day for 12 weeks. The headphones were then taken off for four weeks and then put on again in regular intervals for 22 weeks. At the end of the trial, about seven in ten said that their tinnitus had become quieter and less annoying. On average it halved the intensity of their symptoms. Those who were given the control treatment experienced â€œlimited and non-significant changesâ€.
The brain â€œunlearnsâ€
With Acoustic Coordinated Reset (ACR) the clinical trial showed that the brain manages to “unlearn” the neurological processes which cause it to generate the “phantom” sounds of tinnitus.
The clinical trial was led by Professor Peter Tass at Jülich Research Center in Germany. The results are published in the journal Restorative Neurology and Neuroscience.
Acoustic Coordinated Reset (ACR) was originally developed from therapies for neurological diseases such as Parkinson's.