How blind people use their hearing in everyday life
For blind people and people with severe visual impairment, hearing is important for spatial orientation in addition to communication. In principle, acoustic impressions are considered more reliable than optical ones, and it is not without reason that optical illusions are more often talked about. People with impaired vision or vision make much more use of acoustic impressions. That is why their hearing is better trained: blind people hear better. They perceive sounds and change them better, for example traffic noise under a bridge or near a wall in a house. Estimating and localizing acoustic signals contributes significantly to orientation. Sometimes blind people also use a form of echolocation by gently clicking their tongue and recording the reflection of the sound.
The acoustic signals are always combined by blind and partially sighted people with impressions of their sense of touch obtained by spatial scanning with a stick.
The interpretation of spoken words in a conversation is also better developed among blind and partially sighted people. They can usually perceive and classify nuances in speech and emotions well. Blind and partially sighted people also use these skills to 'experience' films in the cinema or on television using audio descriptions, where a speaker describes the scenes. The images are created in the mind.
Development of brain areas for the senses
However, the fact that blind people hear better is not only due to training and adaptation. In people who are blind or severely visually impaired from birth or early childhood, the brain develops differently. In a study by the Schepens Eye Research Institute of Massachuetts Eye and Ear, the brain activity of twelve people who were born blind or became blind as babies was examined using MRI scans.1 The analysis showed that in the people studied, the brain areas are used and wired differently than people with normal vision. The visual cortex, the part of the cerebrum responsible for visual impressions, also showed brain activity. However, it processed different information – often in combination with the auditory cortex, which processes acoustic stimuli. The researchers see this as one of the reasons why blind people can localize and differentiate sounds better.
Good hearing aids are especially important for blind people
Because it is so important for blind people to hear better, hearing loss has particularly serious consequences for them. For them, and also for people with poor vision, it is all the more important to identify poor hearing at an early stage and, if necessary, initiate adjustment with hearing aids. A hearing care professional can provide detailed information about this.
