Hearing loss

A reduction in the ability to perceive sounds, occurring on a spectrum from mild (difficulty hearing soft sounds or speech in noisy environments) through moderate and severe to profound (inability to hear most sounds without amplification). Hearing loss may be unilateral (one ear) or bilateral, congenital or acquired, and may affect different frequency ranges differently — some people lose high-frequency perception while retaining low-frequency hearing, or vice versa. In accessibility, recognising hearing loss as a spectrum is critical because it means different people need different accommodations: some benefit from captioning, others from amplification or frequency shifting, and many from a combination of audio modification and visual alternatives. The binary framing of "hearing" versus "deaf" misses the large population with partial hearing who benefit from enhanced audio control rather than complete substitution with another modality.