The sense of hearing acts as one of the body’s first warning systems and the irritation caused by unexpected or unusual sounds can bring us to a marginal, fight-or-flee state, ready to react to a potential hazard.
Such sounds can be not only annoying but also physically damaging since very loud noise can cause damage to the cochlea. Prolonged sensory overload exhausts the outer capillary cells and renders the internal cochlear amplifier insufficient. A temporary hearing loss – that is, a change in the auditory threshold – can develop until the external auditory cells recover with the silence afforded during nighttime sleep. This symptom is often the first to occur in people exposed to noise despite the fact that they cannot readily appreciate its significance.
Continuous exposure to the sound develops a permanent shift in the hearing threshold. The main factors for this condition are two:
- The overall exposure to sound (combination of duration and volume)
- The individual sensitivity of each person
Hearing impairment due to noise has been a known problem for a very long time, but legislation has only recently been enhanced in order to include preventative measures. A common way of preventing traumatic hearing loss is the use of special earplugs.