7.9: Hearing Impairments
- Page ID
- 139754
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)Hearing loss occurs when sound transmission or inner ear function is disrupted, reducing the brain’s ability to interpret sound and maintain balance.
- Explain how disruptions to normal sound transmission or sensory cell function in the ear lead to different types of hearing loss.
Hearing Loss and Ear Problems
About one third of people aged 70 and older experience some degree of hearing loss. As you have learned, hearing relies on a series of steps that transform sound waves in the air into electrical signals the brain can interpret. These signals travel from the inner ear to the brain through the auditory nerve. For normal hearing to occur, all the parts of the ear — from the tympanic membrane to the cochlea — must be healthy and working properly.
Age-related hearing loss (presbycusis) develops gradually in most individuals as they get older. Typically, lower-pitched sounds remain easier to hear, while higher-pitched sounds and normal conversation — especially in noisy environments — become harder to understand. Many people benefit from hearing aids, which help amplify sound and improve communication.
Hearing loss can also result from causes other than aging. For instance, a buildup of earwax in the ear canal can block sound waves and cause temporary conductive hearing loss. Exposure to very loud sounds — either suddenly, such as an explosion, or repeatedly over time, like loud music or machinery — can permanently damage the sensory hair cells in the cochlea. Once these hair cells are destroyed, they do not regenerate, leading to irreversible hearing loss.
Another common symptom is tinnitus, or “ringing in the ears,” which can be triggered by loud sound exposure or by certain medications (for example, high doses of aspirin or some diuretics) that are toxic to the ear’s sensory cells. In addition to hearing loss, damage to parts of the inner ear can also cause balance problems, dizziness, or vertigo due to vestibular dysfunction, which leads to impairments in the sense of equilibrium.
A 2025 survey by the Royal National Institute for Deaf People (RNID(opens in new window)) found that hearing problems from loud music are surprisingly common — 58% of Gen Z respondents (ages 18–28) reported experiencing tinnitus, temporary hearing loss, or both after music exposure. While these effects may start as temporary, repeated exposure can make them permanent.
In short, loud sound damages the cochlear hair cells and their nerve connections (synapses). The more often these cells are overstimulated, the higher the risk of permanent noise-induced hearing loss and chronic tinnitus, both of which can seriously impact communication, learning, and quality of life.