What causes hearing loss?

The human sense of hearing is always on, unlike our sense of sight. “Sounds give you sensory input that is not limited by field of vision,” says Seth Horowitz, neuroscientist and author of the book, Universal Sense: How Hearing Shapes the Mind. Early humans, when hunting at night, relied on their sense of hearing because it was too dark to see. A rustle of leaves notifies that someone or something is nearby. Likewise, today, even when we’re sleeping, our sense of hearing is the thing that gets us up in the morning, recognizing the sound of our alarm clock.

Because our sense of hearing is ever-present, we may not think about it very often – until we notice changes in our hearing. There is no one single cause for hearing loss; in fact, hearing loss may occur at any age, to anyone.

Noise-induced Hearing Loss

Noise-induced hearing loss may occur in a single event of traumatic exposure to noise, or over a long period of time at potentially damaging decibels. Exposure to dangerous levels of noise damages our inner ear hair cells. Sounds at or above 85 decibels (dB) are considered dangerous, with risk for hearing loss increasing the longer a person is exposed. Sounds that register at 85 dB include a running construction truck engine or busy city traffic. Yet, we are sometimes exposed to sounds louder than that – a 12-gauge shotgun, for example, registers at 165 dB, while a chainsaw or rock concert clock in at 115 dB.

In recent years, there has been a rise in teen hearing loss, due to usage of in-ear headphones, which could rise to dangerous volumes, for long periods of time. Additionally, 60% of veterans who return from combat zones in Iraq and Afghanistan have reported cases of hearing loss and tinnitus. An explosion, sharp bursts of weapons, and being near the running engines of vehicles for long periods of time have detrimental effects on hearing. Occupational hearing loss is also common; the Occupational Safety & Health Administration reports that approximately 30 million people in the US are occupationally exposed to hazardous noise .

Age-related Hearing Loss

Age-related hearing loss, also known as presbycusis, occurs naturally as we age. Approximately one in three people over the age of 60 in the US experience some degree of hearing loss, while 50% of people over 75 have difficulty hearing. Commonly, age-related hearing loss results from changes in the auditory system: the inner ear hair cells that send signals in the brain naturally die and do not regenerate, which causes difficulty in the brain registering sound. Often times, presbycusis is difficult to differentiate from noise-induced hearing loss – especially after a lifetime of exposure to different levels of noise.

Injuries, Infections, Diseases, Medications

In some cases, trauma to head, neck, and ear area may cause hearing loss. Ear infections, blockages in the ear canal, impacted earwax, and physical injury to the eardrum may also lead to hearing loss. Certain congenital conditions such as otosclerosis, which is a disorder of bone growth within in the ear, as well as Meniere’s disease, may cause hearing loss. Additionally, there are certain classes of ototoxic (poisonous to the ear) medication that damage inner ear cells, causing hearing loss. These drugs include chemotherapy medication, as well as aminoglycoside antibiotics and some diuretics.

   You don’t have to live with untreated hearing loss. 

Contact us today to schedule a hearing test with one of our audiologists.  

Orange County Physicians’ Hearing Services – (949) 364-4361