Research suggests that those with hearing impairment or loss may be at a greater risk for deterioration of quality of life, as captured by a quote from Helen Keller: "Blindness cuts us off from things, but deafness cuts us off from people." Hearing impairment and loss of hearing, regardless of source or age, also limits experiencing the many benefits of sound on quality of life. In addition to the interpersonal social benefits, new studies suggest the effects of nature sounds, such as birds chirping and water, can positively affect an individuals capacity to recover after being stressed or to increase cognitive focus. Quality of life questionnaire
Hearing loss is typically quantified by results from an audiogram; however, the degree of loss of hearing does not predict the impact on ones quality of life. The impact that NIHL can have on daily life and psychosocial function can be assessed and quantified using a validated questionnaire tool, such as the Hearing Handicap Inventory for the Elderly (HHIE). The HHIE is considered a "useful tool for quantifying the perceived emotional and social/situational consequences of hearing loss." The original tool was designed to test adults 65 years of age and older; however, modified versions exist. For adults the Hearing Handicap Inventory for Adults (HHIA) can be used and for adolescents the modified 28-item Hearing Environments And Reflection on Quality of Life (HEAR-QL-28) can be used.
While healing, an over-expression of glutamate receptors can result in temporary tinnitus, or ringing in the ears. Repeated ruptures at the same synapse may eventually fail to heal, leading to permanent hearing loss.Prolonged exposure to high intensity noise has also been linked to the disruption of ribbon synapses located in the synaptic cleft between inner hair cells and spiral ganglion nerve fibers, leading to a disorder referred to as cochlear synaptopathy or hidden hearing loss. This disorder is cumulative and over time, leads to degeneration of the spiral ganglion cells of the inner ear and overall dysfunction in the neural transmission between auditory nerve fibers and the central auditory pathway. The most common symptom of cochlear synaptopathy is difficulty understanding speech, especially in the presence of competing noise. However, this type of hearing impairment is often undetectable by conventional pure tone audiometry, thus the name "hidden" hearing loss. Acoustic over-exposure can also result in decreased myelination at specific points on the auditory nerve. Myelin, an insulating sheath surrounding nerve axons, expedites electrical impulses along nerves throughout the nervous system. Thinning of the myelin sheath on the auditory nerve significantly slows the transmission of electrical signals from hair cell to auditory cortex, reducing comprehension of auditory stimuli by delaying auditory perception, particularly in noisy environments. Individual susceptibility towards noise
There appear to be large differences in individual susceptibility to NIHL.