Researchers Find Ringing in Ears Tied to Faulty Brain Function
January 20, 2011 – Tinnitus – the persistent ringing heard by about 40 million people in the United States – is related to the brain trying to protect itself against overwhelming auditory stimuli, say neuroscientists at Georgetown University Medical Center (GUMC).
Lead investigator and GUMC neuroscientist Josef P. Rauschecker and his research team note in the Jan. 13 issue of Neuron that the same process that causes tinnitus may be responsible for chronic pain and other perceptual disorders.
“We believe that a dysregulation of the limbic and auditory networks may be at the heart of chronic tinnitus,” Rauschecker says. “A complete understanding and ultimate cure of tinnitus may depend on a detailed understanding of the nature and basis of this dysregulation.”
Dysregulation refers to the impairment of a regulatory mechanism in the body.
The absence of sound caused by age-related hearing loss, heavy exposure to noise or an accident can force the brain to produce sounds to replace what is missing, the researchers say.
Tinnitus results when the brain’s limbic system, which is involved in processing emotions and other functions, fails to stop these sounds from reaching conscious auditory processing, according to the GUMC study.
Functional lapses in certain areas of the brain have also been implicated in altered mood states and chronic pain.
“Both of these conditions may also involve the inability to suppress unwanted sensory signals,” Rauschecker says.
The problem isn’t curable, but antidepressants and masking noise to diminish focus on the ringing sensations appears to help some patients.
The National Institute on Deafness and Other Communication Disorders, the Tinnitus Research Consortium, the Tinnitus Research Initiative and the Skirball Foundation supported the study.