The mystery of tinnitus

By Jerome Groopman. February 9, 2009
Tinnitus is one of the most common clinical conditions in the United States.

I noticed the sound one evening about a year ago. At first, I thought an alarm had been set off. Then I realized that the noise—a high-pitched drone—was mainly in my right ear. It has been with me ever since. The tone varies, from a soft whoosh like a shower to a piercing screech resembling a dental drill. When I am engaged in work at the hospital or in the laboratory, it seems distant. But in idle moments it gets louder and more annoying, once even jarring me from a dream.

Tinnitus—the false perception of sound in the absence of an acoustic stimulus, a phantom noise—is one of the most common clinical syndromes in the United States, affecting twelve per cent of men and almost fourteen per cent of women who are sixty-five and older. It only rarely afflicts the young, with one significant exception: those serving in the armed forces. Tinnitus affects nearly half the soldiers exposed to blasts in Iraq and Afghanistan.

This past August, I visited the University of Buffalo, which houses one of the major clinical and research centers for the evaluation and study of tinnitus. After filling out a detailed questionnaire, I met with Christina Stocking of the Speech-Language and Hearing Clinic, who has a doctorate in audiology and specializes in the condition. Stocking thought that I might have suffered noise trauma during a youth spent on the New York City subways. Sitting in the first row of a rock concert exposes you to between a hundred and ten and a hundred and twenty decibels; the screech of the New York subways can reach about a hundred and fifteen decibels. Moreover, since much of the New York subway system is underground, the noise reverberates in the tunnels, unlike in Boston, where many of the trains are above ground and noise dissipates, or in Paris, where several metro lines run on rubber wheels.

Normally, the outer ear, known as the pinna, collects sound waves and directs them into the ear canal, which carries the sound waves to the eardrum. In turn, the eardrum vibrates, and these tremors are picked up by the three tiny bones in the middle ear: the malleus (resembling a club), the incus (shaped like an anvil), and the stapes (similar to a stirrup). These bones amplify the sound vibrations and transmit them to the inner ear, where the cochlea converts the vibrations into electrical impulses, which travel from the acoustic nerve to the part of the brain that processes sound, the auditory cortex. Tinnitus can be temporary, caused by excess wax, an infection of the inner ear, or the toxic effects of drugs like aspirin (which appears to weaken the neural signals from the ear to the brain) or those used to treat cancer. Some people with normal hearing develop spontaneous tinnitus when placed in total silence; this is believed to be a response of the auditory cortex to the abnormal absence of all ambient sounds. But the majority of people with chronic symptoms develop them in conjunction with hearing loss. With the recent proliferation of MP3 players, rates of hearing loss and tinnitus may rise sharply in the coming years. A recent European Union study has projected that as many as ten million Europeans may be at risk of developing severe hearing loss as they age; and, according to the American Academy of Audiology, noise-induced hearing loss affects about one out of every eight children in the United States.

The range of tinnitus’s severity is as wide as the ways of describing the syndrome. Martin Amis, in “Money,” characterizes the tinnitus that his character John Self suffers as “jet take-offs, breaking glass, ice scratched from the tray.”

In “A Pair of Blue Eyes,” Thomas Hardy’s William Worm complains of “people frying fish: fry, fry, fry, all day long in my poor head.” Some patients also suffer from hyperacusis, in which certain sounds are amplified in a painful way. As part of a standard evaluation, patients are given a series of tests: a tympanogram, to determine how the eardrums respond to air pressure; an assessment of the cochlea’s response to sound; and a standard audiogram, to test the frequency and intensity of sounds that define the span of hearing. Although my eardrums functioned well, Stocking said, the last two tests showed signs common to hearing loss at high frequencies, usually owing to age and noise trauma.

The audiologists at the Buffalo clinic see between a hundred and fifty and two hundred tinnitus patients a year, nearly all of them referred by physicians because the noise is disrupting their lives. Last May, David Nowak, a sixty-four-year-old retired machine repairman, had an ear infection that his doctor treated with antibiotics. Shortly thereafter, he heard a loud horn in the street, and has been plagued by tinnitus ever since. “It’s so loud that I can’t drown it out,” he told me. “It is a high-pitched squeal most of the time.” Nowak said that, before the tinnitus, “I didn’t have a care in the world—I cut the grass and I played with my granddaughter.” Now, he said, “My life has come to a halt. I can’t do anything. I can’t concentrate.” One Sunday, he told me, he went out and stood by a metal flagpole during a storm, hoping that lightning would strike, and that he had gone to the cemetery and “begged my mother to take me. I wish I would pass away.”

Tinnitus may have been described as early as the Seventeenth Dynasty, in Egypt (1650-1532 B.C.): an ancient Egyptian text, the Medical Book from Crocodilopolis (circa 150 B.C.), contains references to a “humming in the ear.” Treatment involved pouring herbs, oil, frankincense, tree sap, and soil into the ear using a reed stalk. The earliest undisputed description of the condition comes from Hippocrates, who used three words to describe the problem: echos, meaning sound; bombos, denoting buzzing; and psophos, indicating a slight sound. (Our word “tinnitus” derives from the Latin tinnire, meaning to ring.) The Greco-Roman therapy ranged from holding one’s breath in an effort to expel offending humors from the ear to placing honey, vinegar, cucumber juice, and radish extract in the ear. Hippocrates did make an observation that serves as the foundation for modern therapy: “Why is it that the buzzing in the ear ceases if one makes a sound? Is it because the greater sound drives out the less?”

Jerome Groopman