The Science of Hearing

The Science of Hearing There are more than 10 million people in the UK with some form of hearing loss and 3.7 million of these are aged between 16-64. Did you know that by 2031, it is estimated there will be 14.5 million people in the UK with hearing loss? While it takes an average of 10 years for people to address their hearing loss, this graphic will help you understand how your hearing works, identify the the warning the signs, and what to do when things go wrong. The ear The ear consist of 3 parts: Outer Ear The Pinna is shaped to capture sound waves into the ear canal. Pinna Ossicles Vestibular Nerve Middle Ear Includes the ossicles (stapes, incus and malleus), 3 of the smallest bones in the body. These combine with the eardrum to send sound to the cochlea. Inner Ear Includes the vestibular and cochlea. The vestibular controls balance and the cochlea transmits sound. Vibrations from the sound waves stimulate tiny inner and outer hairs which stimulate an electro-chemical signal to the brainstem. Ear canal Eardrum Cochlea Cochlear Nerve Sound and the brain The brain processes sound signals at a number of different levels: TWEET! TWEET! BANG A reflex which makes us jump Auditory cortex where the sound is Other brain areas, which process the sound, and make a decision about whether evaluated and registered it has heard the sound before, and determine an appropriate response - run, laugh, cry, etc. Our response depends on a number of factors- primarily whether we're awake or asleep. When we're asleep, sound enters the auditory cortex and reflexes can still occur - but the other brain areas will not be activated and there is no conscious perception. When we're awake, all three levels of response are active. When things go wrong If you have a hearing problem, one or more areas of the ear function may not be working correctly. Conductive hearing loss - Outer or middle ear problems lead to inefficient transfer of sound - the cochlea still works but may not receive enough information. Sensorineural hearing loss - Sound is sent to the cochlear but then not fully passed on to the auditory cortex. Most commonly this is because of gradual deterioration of outer hair cells - which become reduced by about 70% by the age of 70. Hearing aids work well with this type of hearing loss. It is also possible that the brain may not be passing on information very well, or at all. How Hearing Aids help hAnAINM Hearing aids have been developed over the years so that sophisticated algorithms can be used to calculate how they should sound. This depends on the results of the hearing test and how the audiologist fine tunes the output for individual needs. A conductive hearing loss is straight forward as many cases the ability to hear all frequencies has been impaired in a similar way. Voices and various other sounds appear quieter. Applying the right level of amplification can therefore work well for those suffering this type of hearing loss. Sensorineural hearing losses are more common if a little trickier to help. For many people this type of hearing loss means that their ability to hear certain frequencies of sound has been impaired leading to a lack of clarity. A modern hearing aid can be programmed to help with this type of hearing loss by amplifying separate frequencies of sound to varying degrees. This approach is not unlike a graphic equalizer on a complicated hi-fi system. Sources: http://hearinglink.org/how-the-ear-works? gclid=COqXo4_lyslICFTDJIAodoloAQg Pleasure of Sound HIDDEN HEARING WE LISTEN, YOU HEAR