Editing Hearing loss (section)

==Pathophysiology==
[[File:Journey of Sound to the Brain.ogg|thumb|How sounds make their way from the source to the brain|275x275px]]
Sound waves reach the outer ear and are conducted down the ear canal to the [[eardrum]], causing it to vibrate. The vibrations are transferred by the 3 tiny ear bones of the [[middle ear]] to the fluid in the inner ear. The fluid moves hair cells ([[stereocilia]]), and their movement generates nerve impulses which are then taken to the brain by the [[cochlear nerve]].<ref>{{cite web|title=How We Hear|url=https://www.asha.org/public/hearing/how-we-hear/|website=American Speech-Language-Hearing Association|access-date=2 March 2018}}</ref><ref>{{cite web|title=How We Hear|url=https://www.sc.edu/ehs/training/Noise/hearing.htm|archive-url=https://web.archive.org/web/20170501041002/http://www.sc.edu/ehs/training/Noise/hearing.htm|archive-date=1 May 2017|url-status=dead}}</ref>  The auditory nerve takes the impulses to the brainstem, which sends the impulses to the midbrain. Finally, the signal goes to the auditory cortex of the temporal lobe to be interpreted as sound.<ref>{{cite web|title=How Do We Hear?|url=https://www.nidcd.nih.gov/health/how-do-we-hear|publisher=NIDCD|date=January 3, 2018}}</ref>

Hearing loss is most commonly caused by long-term exposure to loud noises, from recreation or from work, that damage the hair cells, which do not grow back on their own.<ref>{{cite web|title=What Is Noise-Induced Hearing Loss?|url=https://www.noisyplanet.nidcd.nih.gov/parents/what-is-noise-induced-hearing-loss|publisher=NIH – Noisy Planet|date=December 27, 2017}}</ref><ref name=NIOSH>{{cite web|title=CDC – Noise and Hearing Loss Prevention – Preventing Hearing Loss, Risk Factors – NIOSH Workplace Safety and Health Topic|url=https://www.cdc.gov/niosh/topics/noise/preventhearingloss/riskfactors.html|publisher=NIOSH/CDC|access-date=3 March 2018|date=5 February 2018}}</ref><ref name=Sch2017 />

Older people may lose their hearing from long exposure to noise, changes in the inner ear, changes in the middle ear, or from changes along the nerves from the ear to the brain.<ref>{{cite web|title=Age-Related Hearing Loss|url=https://www.nidcd.nih.gov/health/age-related-hearing-loss|publisher=NIDCD|date=18 August 2015}}</ref>