Understanding Terminology in the Study of Hearing Disorders
Terminology addressing hearing abilities, hearing status, or hearing levels has become more acceptable than impairment-centered terminology, which can have a negative connotation. Terminology will continue to evolve as language is always evolving. It is essential for Speech-Language Pathologists (SLPs) and audiologists to use clear, consistent, and culturally sensitive terminology whenever possible.
However, it's important to note that employers and publications may have different policies on the use of person-first and identity-first language. Additionally, terminology in the law and in clinical documentation may not always align with the terminology preferred by some individuals who are deaf and hard of hearing. Terms used to describe audiological assessment have different values or interpretations assigned to them depending on context and cultural perspective. For instance, some people feel “hearing loss” should only be used to describe hearing loss after birth, not to describe those born without the ability to hear.
This article aims to clarify the terminology used in the study of hearing disorders, covering aspects from audiological assessments to various hearing conditions and assistive devices.
Audiological Assessment and Professionals
An audiogram is a chart that represents a person’s hearing ability, determined by a hearing test. An audiologist specialises in identifying and assessing hearing and balance problems. They recommend and provide appropriate support, products and treatments to help alleviate the effects of hearing loss. Audiologists can work both privately and for the NHS.
Common Hearing Conditions
Several conditions can affect hearing, each with its specific characteristics:
- Acute otitis media, or glue ear, is a short-term ear infection that often comes on suddenly.
- Chronic otitis media is a long lasting or recurring infection in the middle ear.
- Cholesteatoma is a condition of the middle ear that generally starts with a hole in the ear drum; usually in the upper part of the drum. This can become infected and the ear drum sheds dead skin which mixes with other debris in the ear to form a mass. If left untreated this can grow causing damage and may lead to hearing loss, tinnitus and sometimes balance problems.
- Meniérè’s disease is a rare condition that affects the inner ear. It can cause vertigo, tinnitus, hearing loss and a feeling of pressure or fullness in the ear.
- Noise-induced hearing loss is when we are exposed to sounds that are too loud, or loud sounds that last a long time, sensitive structures in our ear (hair cells) can be damaged.
- Otosclerosis is a condition which results in the abnormal growth of bone in the middle ear. It can cause conductive hearing loss. The excess bone prevents the ossicles in the middle ear from moving freely.
- A perforated eardrum signifies a hole or tear in the eardrum.
- Hyperacusis is abnormal discomfort caused by sounds that are tolerable to listeners with ordinary hearing.
- Most people find their hearing gets worse as they get older - this is called age-related hearing loss or presbycusis.
Additionally, a disorder can affect the processing of auditory information within the brain. Conductive deafness is when sound cannot pass freely through the outer or middle ear. This is usually caused by a blockage in the outer or middle ear from an infection or a build up of wax. If the cause is wax this can be removed by an audiologist.
Tinnitus is experienced as noise in the ears or heard. Pulsatile tinnitus is normally described as rhythmic noise that beats in time with your pulse.
Ototoxic refers to drugs that may be damaging to the ear or hearing.
Anatomy of the Inner Ear
Hearing Aids and Assistive Devices
Hearing aids amplify weak sounds to a level that the user can hear. They also ensure that strong sounds are not amplified too much to avoid discomfort.
Analogue hearing aids have a microphone that picks up sound and converts the sound into small electrical signals. These electrical signals are then amplified (made louder) and fed into an earphone on the hearing aid so you can hear them.
Digital hearing aids take signals from the microphone and convert this into a code. Some hearing aids have multiple microphones to help detect the direction of a sound source. This helps the hearing aid to focus more on sounds coming from the front of the person, rather than the side or behind.
Different types of hearing aids include:
- Behind-the-ear (BTE) aids: BTE aids have a mould that fits inside the ear, while the rest of the aid sits behind the ear.
- Receiver-in-the-ear (RITE) aids: RITE, or loudspeaker-in-the-ear aids are smaller than BTE aids, because some part of the device sits inside the ear. They are not as small as ITE or CIC aids. Like open ear BTEs, they can be easier to put in than an ear mould.
- In-the-ear (ITE) aids: ITE aids are small enough to fit inside the ear, although not as small as CIC aids.
- Completely-in-the-ear-canal (CIC) hearing aids.
Conventional ear moulds are not required for open ear fitting. Instead, the hearing aid sits behind the ear and a small tube carries the sound into the ear and is held in place by a small tip and/or sprung plastic projection.
A cochlear implant consists of a microphone and a transmitter outside the head, which send signals to a receiver under the skin which is connected to electrodes implanted in the cochlea. The cochlea is a fluid filled chamber in the inner ear which converts sound to electrical impulses in the auditory nerve. Sound waves enter the cochlea from the middle ear causing the fluid to vibrate. Hair cells are sensory cells in the cochlea that convert sound vibrations into electrical signals that then travel along the auditory nerve to the brain.
Brain stem implants are inserted surgically and can improve hearing in patients with neural hearing loss, which can be caused by cancer of the auditory (hearing) nerve or an auditory nerve that failed to develop properly.
Also known as an induction loop, a loop system is an assistive listening device that can be used with some hearing aids in places where it might be difficult to hear. Loop systems are commonly available in public places such as banks, post offices and theatres.
Different Types of Hearing Aids