Most learning and development takes place by taking in information through the sense of hearing using our ears, through the sense of vision using our eyes and through touch and movement. Of all the senses these three, more than any of the other senses, determine how well we develop from a new born baby to a well adjusted adult that can successfully function in life.
Hearing involves more than just our two ears, as these are only the receptors that gather sound from the outside world. How this information is processed and interpreted in the brain will to a great extend determine how we perceive reality and how we react, behave and express ourselves. The ears and the associated processing centres in the brain form our auditory system.
Listening to the voices around us, that of our mother, father or siblings for instance, is how we acquire understanding of language, and learn to speak. Extensive periods of reduced hearing during the first years of life, though ear infections or medical conditions, will often impact on language and speech development. Imperfections in how we hear or process sounds will often show themselves in how we speak or how well we can read and write.
Sounds received through our right ear is mainly processed in the left brain half and sounds coming into our left ear are mainly processed in the right half. The brain uses these two separate and slightly different signals to calculate location and movement of sounds. The two sides must work well together in order to be able to filter out distracting sounds that come from other sources, for instance, the sound of the mother's or teacher's voice. People with attention deficit are often distracted by unrelated sounds in their environment. Faster transfer of information between the two brain halves, through the Corpus Callosum – the main bundle of connecting fibres between the two brain halves – is of essence.
Reading and writing are complex processes involving not only visual abilities, but also relying on effective auditory processing. The process of reading and writing involves us speaking to ourselves, quietly inside our head and then listening to our ‘brain voice’. Only then are we able to understand what we are reading or writing. Brain scans clearly show that the same hearing processes are activated when we are listening to ourselves in our head during reading or writing as when we are listening to an external voice using our ears. And likewise, we use the same specialised speech production centres in the brain when talking to ourselves in our own brain, as when we are speaking aloud to someone. Poor auditory processing will lead to slow or inaccurate reading and writing. Many people diagnosed with Dyslexia have difficulties in accurately processing fast or very short sounds.