Hearing Disability (English Version)

By Manfred Stoifl (Hearing aid Acoustician) AAHA, Vienna, Austria

Hearing disability is the effect of hearing loss and can have many forms and ramifications

Different forms of hearing loss result in different hearing disabilities. However, all hearing losses have one thing in common, that the ears ability to convert sounds into electrical stimuli or to transmit said stimuli to the brain, is impaired. 

Understanding the meaning of sounds and the ability to quickly and subconsciously work with information from the ears is a learned / acquired ability. This fully automatic and subconscious process is strongly depended on clear and full spectrum auditory input in the form of electrical stimuli,with as high a resolution as possible coming from both our ears and continuous practice throughout our life.

A hearing disability arises when our brain cannot assign meaning to stimulation coming from the ears. This could be due to a fault in the ear, the conduction from the ear to the brain or the brains inability to quickly and accurately assign meaning. Most likely it is a combination of all 3 factors and time. The less resolution a signal has, the more complex is the brains task to assign a unique meaning to it. 

Initially hearing loss will not result in a disability, but might just manifest itself by the environment slowly becoming less noisy as some of the very soft sounds becoming inaudible. This however means that the auditory centres in the brain are deprived of crucial input. Over time the degree of hearing loss increases and the amount of information provided to the brain degreases. This causes our central processing to become less fast and less accurate due to the lack of training. 

Initially this manifests itself by understanding some people less good in noisy or adverse acoustic environments, or by tiring more easily while listening under such circumstances. As time progresses with or without an increase in actual hearing loss the brain gets slower and worse processing sounds. A problem which initially was only present under certain adverse listening conditions becomes more and more apparent.

It is a self-perpetuating vicious cycle feeding on itself. The less we hear the less our auditorycentres in the brain get to work the slower and less accurate they get. The slower and less accurate they get, the more a hearing disability become apparent and affects daily life and communication. 

Over time, more and more “brain power” needs to be assigned to the process of assigning meaning to sounds, and a process which was supposed to work subconsciously suddenly happens in our consciousness. At that stage one tries to reduce the effect of the hearing disability, at first rather successful, with contexting. This is of course very inefficient and tiring way of hearing and drives people gradually to avoid conversations altogether.