Researchers have searched for centuries for an effective way to end the maddening, continuous ringing in the ears that some people suffer. Most of the so-called cures to treat the condition known as tinnitus were quack treatments, bizarre devices, or ineffective regimens.
The affliction can be expensive. According to industry experts, about one billion dollars is doled out in the form of disability payments every year by the Veterans Administration. The VA reports that the most common physical affliction of military personnel returning from the Middle East wars is tinnitus.
Now research scientists have found a method to reduce the constant ringing. The procedure involves stimulating a certain nerve in the neck while playing a series of tones that actually work to ‘reboot’ the brain. The paper, “Reversing pathological neural activity using targeted plasticity,” has been published in the journal Nature.
It’s estimated that millions of people suffer from tinnitus. Some, like military personnel returning from war zones, were exposed to the sounds of guns, explosions, aircraft and other high-decibel producing things. Many find they’re left with hearing damage. Those that have suffered damage from noise often discover they hear a constant high-pitched tone—others might hear a continuous rushing, clicking or whooshing noise that they can only escape during sleep. Sufferers of tinnitus may have one ear or both affected.
Although many tinnitus sufferers have a low level affliction that becomes unnoticeable when they are in an environment with background noise, there are others that suffer from a ringing or whooshing sound so loud that it interferes with their daily life. For them, the new therapy could be a godsend.
A co-author of the study done at the University of Texas, Michael Kilgard,Ph.D., associate professor of behavior and brain sciences, stated in the university website EurekAlert! that “Brain changes in response to nerve damage or cochlear trauma cause irregular neural activity believed to be responsible for many types of chronic pain and tinnitus.”
That belief is based on evidence that the brain attempts, but fails, to properly adjust for a physical trauma to the inner ear, hearing loss, or some minor nerve damage.
Kilgard explained, “We believe the part of the brain that processes sounds—the auditory cortex—delegates too many neurons to some frequencies, and things begin to go awry.”
To test that hypothesis and determine whether the disorder could be reduced or eliminated entirely the university team decided to reboot the neurons of lab rats through a retraining regimen. If successful, the neurons would stop overcompensating and reset to their normal level.
The experiments—which employed electrical stimulation of the vagus nerve (a primary nerve in all mammals that travels from the brain through the neck and into the abdomen) in rats known to have tinnitus—were seeking to reboot the information traveling along the nerve fibers. In addition to the electrical stimulation the researchers also exposed the rats to a high-pitched tone.
According to the study, vagus nerve stimulation—known as VNS—releases certain chemicals that act as neurotransmitters. Those chemicals encourage changes in the brain that can affect the brain’s hearing process.
The results were very encouraging. While the control group of rats that received either electrical stimulation or the high tone showed no reduction of the tinnitus, those rats that received both stimulation and the tone were cured of the chronic ringing for more than three months.
It proved that the hypothesis had merit and that the brain’s neurons can be retrained—rebooted—to learn how to effectively compensate for minor hearing damage.
Calling it very encouraging, the researchers plan to begin conducting clinical trials later in 2011. “We are returning the brain from a state where it generates tinnitus to a state that does not generate tinnitus. We are eliminating the source of the tinnitus,” Kilgard stated.
Previous treatments to deal with the disorder have tried to mask the chronic ringing. This new approach actually eliminated tinnitus because it “not only reorganized the neurons to respond to their original frequencies, but it also made the brain responses sharper,” according to the university study.
The study also refers to the current treatment of nearly 50,000 patients suffering from depression or epilepsy using VNS. The stimulation permits manipulation of brain cells without the use of drugs. With the addition of sound to reboot the neurons and guide them back to normal functioning, tinnitus can be eliminated and after a period of time—it’s hoped—permanently cured.
Yet even if the process only proves to last a certain period of months, the neurons can just be rebooted again to return to a normal state.
Because no drugs are used in the therapy, after the clinical trials in Europe the procedure is expected to be made available to tinnitus sufferers very quickly.