Have you ever been in the middle of the worst day – until you hear you hear your favorite song on the radio? Or received a postcard from your best friend of many, many years? Perhaps a scent in the air brings back happy childhood memories of loved ones. Instances like these are made possible by a chemical reaction in the brain, no matter the sense through which you’re experiencing it. It is the focus of a study by University of Washington Vancouver research scientist Christine Porfors, with help from David Perkel, professor of biology and otolaryngology at the University of Washington. The $1.6 million study will examine the effects of dopamine on hearing health and is backed by the National Institutes of Health.
What is Dopamine?
Dopamine is a neurotransmitter in the brain. It is essentially a chemical messenger that shuttles across the spaces between cells. They bind to molecules called receptors, which then relay signals carried by the neurotransmitters from one cell to its neighbor. Dopamine is responsible for how we move, what we eat, and even how we learn. It also regulates mood, memory, and behavior and stimulates the heart, metabolism, and circulation.
Though dopamine is mostly produced in two main areas of the brain no bigger than a postage stamp, it helps so much of the body function smoothly. Decreased levels of dopamine have been associated with conditions such as Parkinson’s disease and schizophrenia. Parkinson’s disease is a condition in which motor skills and speech are affected. Levels of dopamine naturally decrease between the ages of 20-80, while those with Parkinson’s disease have damaged nerve cells in dopamine-producing parts of the brain.
How are Dopamine and Hearing Connected?
Dopamine and hearing have one major thing in common: the brain. Though hearing is a sense we associate with our ears, the brain actually translates the noise gathered by our ears into information. The organ of Corti is the receptor organ for hearing, located in the cochlea, that converts auditory signals and is a catalyst for cell-to-cell communication to the brain along cochlear nerve fibers. The most common type of disabling hearing loss, sensorineural hearing loss, occurs when this pathway is damaged. Aging and noise exposure are very common causes of this type of hearing loss. Hearing aids and cochlear implants can indeed help this condition, however there is no cure.
A study on the effect of a protein responsible for transporting dopamine to nerve synopses, the aptly named dopamine transporter, was published in the May 2006 issue of the Journal of Neuroscience by French researchers. They found that dopamine is essential in maintaining healthy auditory nerve neurons and how they respond to various sound stimuli.
The University of Washington study of Porfors and Perkel’s looks to explore the effects of dopamine on brain cells, synapses and neural circuits in relation to auditory processing. They suspect neurons may respond differently to sounds and voices when dopamine is introduced. Porfors and Perkel will use recordings of the love songs of male mice singing to female mice with and without genetically engineered Parkinson’s and study the effects on the auditory nerve when they are replayed.
Your Hearing Health
It is common knowledge among hearing health professionals that hearing loss, if left untreated, can lead to a host of other health disorders, including anxiety, social isolation, and depression. Hearing well has been shown to slow the progression of diseases such as dementia and Alzheimer’s and is also helpful for the treatment of other diseases, such as Parkinson’s.
The production of dopamine—and serotonin—have been quite effective in treating patients with Parkinson’s disease and dementia in music therapy. Dan Cohen, a former social worker, has created a Music and Memory program that demonstrates the strong connection between the human brain and music. He has a video on YouTube featuring an elderly man, “Henry,” flopped in a chair until he starts listening to music. Henry becomes animated and begins to hum, afterward singing a few bars of old favorites and answering questions.
Researchers from McGill University have found that even young people benefit from dopamine stimuli produced from sound. Researchers at the Canadian institution studied the brain activity of eight 19-24-year olds while they listened to music they selected. According to PET and MRI scans, dopamine levels increased between six and nine percent.
The body’s natural production of dopamine can be stimulated by several factors. Getting at least 30 minutes of daily exercise is one of them. This alone can benefit your hearing health greatly. Also, eating foods known to increase dopamine production, like bananas, fresh fruits, and vegetables, and eliminating foods high in sugar, fat, and cholesterol is a recipe for success.
Have you experienced changes in your hearing? Has difficulty with communication lead to changes in your mood, causing stress and anxiety? There’s no reason to live with untreated hearing loss. Contact us at Audibel today to schedule a consultation!