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What’s that sound?

This is a transaxial slice of the brain of a 5...

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Tinnitus, or ringing in the ears, is an exceptionally common problem.  As many as 2 million Americans experience this on a daily basis.  It can range from very minor to annoying to debilitating.

Tinnitus is often associated with hearing loss.  Prolonged exposure to loud noises is the most common cause of hearing loss.  It is this loss of hearing that is actually causing the tinnitus.  Say what? Hearing loss actually causes people to hear sounds that don’t really exist? Yes!

People often describe tinnitus as ringing in the ears.  However, the list of sounds that are considered tinnitus is very long.  Other sounds that people might perceive include ticking, clicking, whooshing and buzzing to name a few.

Recent research, published online in the journal Proceedings of the National Academy of Sciences, suggest several new approaches to treatment, including retraining the brain, and new avenues for developing drugs to suppress the ringing.

As a chiropractic neurologist the above statement about retraining the brain got my attention.  This is something that is near and dear to the heart of all chiropractic neurologists.  We use techniques that retrain the brain every day.  We use these techniques to help people with a wide variety of conditions ranging from anxiety to muscular imbalances and pain.

Traditionally, patients with tinnitus are told the problem stems from damaged hair cells inside of the ear.  They are told it is these hair cells that are sending the wrong signals into the brain which interprets them as noise. Turns out, this is not true.

Because each hair cell is tuned to a different frequency, damaged or lost cells leave a gap in hearing, typically a specific frequency and anything higher in pitch.  It is this gap which causes problems for the brain.

Chiropractic neurologists have been saying for a very long time that ringing in the ears is actually brain based.  This new research supports this assertion. Below is information from coauthor of the recent study Shaowen Bao, adjunct assistant professor in the Helen Wills Neuroscience Institute at UC Berkeley

Experiments in the past few years have shown that the ringing doesn’t originate in the inner ear, though, but rather in regions of the brain — including the auditory cortex — that receives input from the ear.

Bao’s experiments in rats with induced hearing loss explain why the neurons in the auditory cortex generate these phantom perceptions. They showed that neurons that have lost sensory input from the ear become more excitable and fire spontaneously, primarily because these nerves have “homeostatic” mechanisms to keep their overall firing rate constant no matter what.

“With the loss of hearing, you have phantom sounds,” said Bao, who himself has tinnitus. In this respect, tinnitus resembles phantom limb pain experienced by many amputees. (From sciencedaily.com)

The neurons that have lost sensory input in the brain are the neurons that are responsible for the perceived noise that people hear.  These neurons have undergone a process called transneural degeneration.  To stabilize these neurons they need more input.  But because they cannot receive it from the hair cells in the ear that are damaged, other areas of the auditory cortex must take over.  This retraining of the brain takes time, but if performed diligently, the results can be phenomenal.

We know this is a possibility because the brain is plastic.  That is, it changes in response to the stress and environmental input it receives. When a finger is amputated, for example, the region of the brain receiving input from that finger may start handling input from neighboring fingers.

Drug therapy is aimed at increasing the levels of the neurotransmitter GABA in the brain.  GABA is the primary inhibitory neurotransmitter.  In order to slow down the firing rate of these over excited cells, we must increase the levels of this inhibitory neurotransmitter.  The good news is there are lots of natural therapies that work to raise GABA levels or drive GABA receptors in the brain.

One way is to use the amino acid taurine.  I use it frequently.  Another is a product called phenibut (Phen-i-bute).  It is a natural GABA derivative that crosses the blood brain barrier and binds to GABA receptors.  I also use this frequently in my practice. These supplements, however, I believe are temporary solutions.  The permanent solution is to retrain the brain.

Tinnitus is a complicated and elusive condition, but we appear to be headed in the right direction in terms of research.  Always remember, the brain holds the key!

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