Central Hearing is the brains ability to find meaning in the electrical stimuli it receives from the cochlea.
Hearing actually happens in the brain.
The brains auditory areas receive electrical stimuli and form patters/pictures out of them, associate them with meaning and/or storing them for future reference. These patterns are comprised of the relation between different pitches and loudness of each component a sound.
For the brain to be able to associate sounds with meaning it needs to build up, maintain and access an extensive “library” of auditory pictures in the memory.
Processing speed, the ability to compare received auditory patterns/pictures as quickly as possible with what’s stored in the auditory memory and/or putting them into context with other auditory or other sensory input, is essential to good central hearing.
Additional information is provided by differentiating and measuring minute time and frequency pattern differences from sounds arriving from different sides.
How Hearing Loss Occurs
As hearing gradually degrades, one becomes less and less aware of all the sounds around us. For a long time this happens unnoticed. Only once sounds get affected which we want/need to hear, like music or speech, are we or others around us gradually becoming aware of a hearing loss.