What Causes Hearing Loss? (video)

Learn the types, prevention and treatments for hearing loss

Learn the types, prevention and treatments for hearing loss

Hearing loss is a common problem among older adults, but it is becoming more prevalent among younger people as well.


While people with mild hearing loss may find it frustrating to hear conversations or television programs, severe hearing loss can pose more serious problems if, for example, someone can’t hear a smoke alarm or misses important medical instructions. Significant hearing loss also can lead to social isolation, which in turn can lead to depression.


In this video, San Diego Health host Susan Taylor talks with Thomas Alexander, MD, a neurotologist and ear surgeon at Scripps Clinic Torrey Pines, about how to help prevent and treat hearing loss.

What causes hearing loss?

To understand the various causes of hearing loss, it helps to know how the ear normally works. Sound travels through the ear canal into the eardrum. The eardrum and attached hearing bones vibrate, which causes movement inside the hearing organ, called the cochlea. There, tiny cells detect that movement and trigger a nerve impulse to the brain.


The most common type of hearing loss happens when the cochlea stops working properly; this is typically due to exposure to noise throughout our lives. A less common cause is conductive hearing loss, which develops when sound transmission from outside to inside the head is physically blocked. Mixed hearing loss is a combination of these.

What are signs of hearing loss?

Most people first notice hearing loss when they can’t hear conversations as well as they used to if there is background noise. The brain actively suppresses high-frequency sounds to allow us to understand speech, and hearing loss interferes with that ability.


“It turns out that our ears are so sensitive and so delicate that our daily lives are too loud for them,” says Dr. Alexander. “The longer we live, the more noise we’re exposed to, the more high frequency hearing loss occurs. Even young people can start to notice that.”

How is noise measured?

Loudness is measured in decibels. While any loud sound can cause hearing loss, how long you hear it also comes into play.


“We know that sound at or above 70 decibels for extended periods of time can cause damage to the ears. A leaf blower is about 85 decibels, and you might be able to be exposed to that for two hours before you have damage,” says Dr. Alexander. “But a jackhammer might be more like 120 decibels, and that can potentially cause instantaneous damage to your ears.”


Even at moderate volumes, sound heard all day long can cause hearing loss over time. One in five adults aged 20 to 29 will have significant hearing loss; between ages 50 to 59, it is one in four. After age 80, hearing loss affects nine out of 10 people.

What is a hearing test?

Dr. Alexander says the first step to treating hearing loss is to schedule a hearing test with an audiologist. The test measures the quietest sound that can be heard at every frequency, along with the movement of the eardrum and the pressure behind it, to determine the type and severity of hearing loss and how best to treat it.

What are treatments for hearing loss?

Hearing aids are the standard treatment for hearing loss, and they range from simple over-the-ear models to very small ones that fit inside the ear canal.


People whose hearing loss is so severe that hearing aids will not help may benefit from a cochlear implant. This surgically implanted device can provide sound by electrically stimulating the hearing nerve. The outpatient surgery, performed while the patient is asleep under general anesthesia, takes about 90 minutes. After a month or so of recovery time, the implant is turned on.


While some hearing loss may be inevitable over time, you can take steps to help minimize it. 


“One way to help keep hearing loss from worsening is to protect yourself from loud noise exposure,” says Dr. Alexander. “Earplugs are the main thing. It’s possible that noise-canceling headphones might be helpful. It’s really just a matter trying to limit the volume of noise you’re exposed to, and especially avoiding long durations of loud volume.”


If you are concerned about hearing loss, talk to your doctor about scheduling a hearing test.