The World of Hearing

Our senses dictate the way we interpret and interact with the world. Hearing, in particular, alerts us to danger, allows us to communicate with others and helps to understand our surroundings.

It is only natural that we would be disconcerted by any degradation in our hearing capacity. However, everything from illness to simple ageing can affect our auditory or hearing ability.

The following information gives an insight into how hearing loss can be tackled, what hearing aids are available, and what types of hearing loss you may experience. This will help you make an informed decision about the best way to improve your hearing.

Types of hearing aid

Digital or analogue?

Digital and analogue devices process sounds differently. Analogue, which is more basic, amplifies electronic signals, while a digital hearing aid processes sound using a small, computerised chip. Digital devices are newer and also designed to reduce background noise.

Behind-the-ear (BTE)

BTE devices are the most traditional type of hearing aid. The unit sits behind the outer ear with an insert that fits the ear canal, which delivers sound via a small plastic tube between the two.

In-the-ear (ITE)

This type of hearing aid is fully contained in a custom-shaped covering that sits in the wearers ear.

Completely in-the-canal (CIC)

CIC hearing aids are less visible than the former two, but also have some limitations with treating more severe hearing loss. The device sits completely within the ear canal.

Bone conduction

People who cannot wear traditional hearing aids may benefit from bone conduction devices. It delivers sound by direct vibrations to the head. This is particularly suitable for those with conductive hearing loss.

CROS/BiCROS

These units are designed to help those with hearing only in one ear. They pick up sound from the side that has little or no hearing and transmits it to the side that can detect sound. BiCROS devices go further and amplify the resultant sound for those with no hearing on one side and reduced hearing in the other.

Types of hearing loss

There are two types of hearing loss which are primarily dealt with through hearing aids:

Conductive hearing loss

This is caused by conditions that restrict the transmission of sound through outer or middle ear to inner ear. It may be caused by blockage in the ear canal; malfunction of the Eustachian tube; problems with the middle ear bones or perforated eardrum. Treatment prognosis for conductive hearing loss is positive in most cases.

Sensorineural hearing loss

Damage to the inner ear results in sensorineural hearing loss. This is also known as nerve deafness, as it often involves the auditory nerve. Sensory, or cochlear hearing loss relates specifically to inner ear problems, while neural means hearing loss from damage to the nerve pathway from the inner ear. This type of hearing loss can include a large variety of impairments, which are often difficult to treat except with hearing aids. Some people may suffer from mixed hearing loss – a combination of the two.

Other types of hearing loss include:

Central hearing loss

This is caused by conditions that affect the central nervous system or brain. Often, people affected by central hearing loss have normal auditory function, but struggle to hear when there is background noise or other difficult listening conditions that makes speech processing more complex.

Functional hearing loss

Caused by a psychological or emotional problem this can be difficult to identify, but is best addressed through psychological treatment.