Understanding the Different Types of Hearing Loss
Hearing loss affects millions of people worldwide, yet many don't realize that it isn't a single condition. There are distinct types of hearing loss, each with different causes, characteristics, and treatment pathways. Knowing which type you or a loved one has is the first step toward finding the right solution.
The Three Main Types
1. Conductive Hearing Loss
Conductive hearing loss occurs when sound cannot efficiently travel through the outer ear canal to the eardrum and the tiny bones (ossicles) of the middle ear. The inner ear is typically unaffected.
Common causes include:
- Earwax (cerumen) buildup blocking the ear canal
- Fluid in the middle ear (common in children with ear infections)
- A perforated (ruptured) eardrum
- Abnormal bone growth (otosclerosis)
- Malformation of the outer ear or ear canal
The good news: conductive hearing loss is often temporary and treatable. Removing a blockage, treating an infection, or undergoing surgery can frequently restore normal hearing.
2. Sensorineural Hearing Loss (SNHL)
Sensorineural hearing loss is the most common type of permanent hearing loss. It results from damage to the hair cells inside the cochlea (the inner ear) or to the auditory nerve itself.
Common causes include:
- Age-related hearing decline (presbycusis)
- Prolonged exposure to loud noise (noise-induced hearing loss)
- Certain medications (ototoxic drugs)
- Viral infections such as mumps or measles
- Genetic or hereditary factors
- Head trauma
SNHL is generally not reversible, but hearing aids and cochlear implants can significantly improve quality of life for those affected.
3. Mixed Hearing Loss
Mixed hearing loss is exactly what it sounds like — a combination of both conductive and sensorineural hearing loss occurring in the same ear. A person may have underlying sensorineural hearing loss while also experiencing a conductive component due to an ear infection or blockage.
Treatment for mixed hearing loss may involve addressing the conductive element medically or surgically, while managing the sensorineural component with hearing aids.
How Hearing Loss Is Measured
Audiologists measure hearing loss in decibels (dB) of hearing level. The degrees of hearing loss are generally classified as:
| Degree | Hearing Threshold | Typical Experience |
|---|---|---|
| Normal | 0–25 dB | Can hear whispers and soft sounds |
| Mild | 26–40 dB | Difficulty with soft speech in noise |
| Moderate | 41–55 dB | Struggles with normal conversation |
| Moderately Severe | 56–70 dB | Needs loud speech to understand |
| Severe | 71–90 dB | Can only hear very loud sounds |
| Profound | 91+ dB | Very little or no functional hearing |
When to See a Specialist
If you notice any of the following, schedule an appointment with an audiologist or ENT (ear, nose, and throat) specialist:
- Difficulty following conversations, especially in noisy settings
- Frequently asking people to repeat themselves
- Turning up the TV volume higher than others prefer
- Sudden hearing loss in one or both ears
- A feeling of fullness or pressure in the ear
Early identification is key. The sooner the type and degree of hearing loss is diagnosed, the sooner an effective management plan can be put in place.