Mixed hearing loss is a combination of two types of hearing problems happening at the same time. One part involves a blockage or damage in the outer or middle ear that prevents sound from reaching the inner ear properly. The other part involves damage to the inner ear itself or the nerve that carries sound signals to the brain. When both problems exist together, the result is mixed hearing loss.
How Normal Hearing Works
To understand mixed hearing loss, it helps to know how sound normally travels through your ear. Sound waves first enter the outer ear and move down the ear canal, where they hit the eardrum and cause it to vibrate. Those vibrations pass through three tiny bones in the middle ear, which amplify the sound and deliver it to the cochlea, a fluid-filled, spiral-shaped structure in the inner ear. Inside the cochlea, specialized hair cells convert those vibrations into electrical signals that travel along the auditory nerve to the brain.
A problem anywhere before the cochlea (outer or middle ear) causes conductive hearing loss. A problem at the cochlea or beyond (the nerve pathway to the brain) causes sensorineural hearing loss. Mixed hearing loss means both types are present simultaneously.
Common Causes
The classic cause of mixed hearing loss is otosclerosis, a condition where abnormal bone growth in the middle ear stiffens one of the tiny bones responsible for transmitting sound. Over time, otosclerosis can progress from a purely conductive problem to one that also damages the inner ear, creating a mixed pattern.
Age-related inner ear damage is another frequent contributor. As you get older, the hair cells in the cochlea naturally deteriorate. If you then develop a middle ear infection, fluid buildup, or earwax blockage on top of that existing sensorineural loss, the combination becomes mixed hearing loss. Chronic ear infections are a particularly common trigger because repeated inflammation can damage both the middle ear structures and, over time, the inner ear as well.
Other causes include head injuries, which can simultaneously disrupt the bones of the middle ear and harm the cochlea or auditory nerve. Certain genetic conditions also play a role. BOR syndrome and CHARGE syndrome can cause mixed hearing loss because they produce malformations in both the middle ear bones and inner ear structures. Pendred syndrome, which involves an enlarged vestibular aqueduct, is another genetic condition that can present with both conductive and sensorineural components.
What It Sounds Like
People with mixed hearing loss typically experience a more significant overall reduction in hearing than someone with only one type. The conductive component makes sounds seem quieter, as if someone turned the volume down. The sensorineural component distorts the clarity of what you do hear, making speech sound muffled or hard to distinguish even when it’s loud enough to detect. Together, these create a situation where sounds are both too quiet and unclear.
You might find yourself turning up the television but still struggling to follow dialogue. Background noise becomes especially difficult to filter out. High-pitched sounds like children’s voices or birdsong may disappear entirely, while deeper sounds remain partially audible but fuzzy.
How It’s Diagnosed
An audiologist diagnoses mixed hearing loss using an audiogram, a test that measures your hearing at different pitches and volumes. The key distinction involves two separate measurements: air conduction and bone conduction.
During air conduction testing, you wear headphones and listen for tones at various frequencies. This tests the entire hearing pathway, from the outer ear all the way to the brain. During bone conduction testing, a small vibrating device is placed on the bone behind your ear. This sends sound directly to the cochlea, bypassing the outer and middle ear completely.
In mixed hearing loss, both tests show reduced hearing, but air conduction results are worse than bone conduction results. The difference between the two measurements is called the air-bone gap. This gap represents the conductive component. The fact that bone conduction is also below normal reveals the sensorineural component. Depending on the underlying cause, air-bone gaps can range from minimal to as large as 60 decibels, and they often vary across different frequencies.
Clinical guidelines from the American Speech-Language-Hearing Association recommend that anyone identified with conductive or mixed hearing loss be evaluated further or referred to a specialist, since the conductive component may be medically treatable.
Treatment Options
Treatment for mixed hearing loss often involves addressing each component separately. The conductive part is sometimes treatable with medication or surgery. If a middle ear infection is contributing, antibiotics or drainage procedures can resolve the blockage. If otosclerosis is the cause, a surgeon can sometimes replace the stiffened bone with a small prosthetic to restore sound transmission.
The sensorineural component is usually permanent. Once the hair cells in the cochlea are damaged, they don’t regenerate. This is where hearing devices become important.
Traditional hearing aids amplify sound through the ear canal and middle ear, which can help with both components if the conductive problem is mild. For more significant conductive issues, bone-anchored hearing systems offer an alternative. These devices bypass the outer and middle ear entirely by sending sound vibrations through the skull bone directly to the cochlea. The most common type involves a small titanium implant surgically placed in the bone behind the ear. Once it heals, you attach an external sound processor that clips onto the implant.
For children under 5 or people who prefer to avoid surgery, nonsurgical bone conduction devices are available. Some attach to the skin with adhesive, while others sit on a headband you wear as needed. In cases of severe or profound mixed hearing loss where neither hearing aids nor bone-anchored devices provide enough benefit, cochlear implants may be considered.
Risks of Leaving It Untreated
People with hearing loss wait an average of 10 years before seeking help, and during that time the consequences extend well beyond missing conversations. Research from Johns Hopkins tracked 639 adults for nearly 12 years and found that even mild hearing loss doubled the risk of dementia. Moderate hearing loss tripled the risk, and severe hearing loss made dementia five times more likely. Brain imaging studies suggest that hearing loss contributes to faster brain atrophy, possibly because the brain is constantly straining to fill in the gaps left by degraded sound signals.
Balance problems are another underappreciated risk. Your ears pick up subtle environmental cues that help you stay steady on your feet. When hearing loss mutes those signals, and your brain is simultaneously working harder to process whatever sound it does receive, the mental multitasking can interfere with the processing needed to walk safely. Falls become more common.
Social isolation tends to creep in gradually. Conversations become exhausting, noisy restaurants feel impossible, and it becomes easier to withdraw. That isolation itself is a risk factor for cognitive decline and depression. Because mixed hearing loss involves two overlapping problems, the overall hearing reduction is often more severe than either type alone, which makes early intervention especially valuable.