Hearing is defined as the process of perceiving, transmitting, and interpreting sound waves from the environment in the brain; through this process, individuals detect and make sense of auditory stimuli in their surroundings (WHO, 2021). Any disruption in this complex process is referred to as hearing loss and can range from mild to severe (Northern & Downs, 2014). Hearing loss can be congenital or may develop later due to various medical, genetic, or environmental factors. In both cases, hearing loss significantly affects an individual’s communication skills, language development, learning processes, and social interaction abilities (Olusanya, Davis & Hoffman, 2019).

According to the World Health Organization, hearing loss ranks as the third most common chronic health condition worldwide (WHO, 2021). Globally, over 1.5 billion people experience some degree of hearing loss at some point in their lives. Of these, approximately 430 million people—more than 5% of the world population—require rehabilitation due to hearing loss, with around 35 million of them being children. The WHO predicts that by 2050, more than 700 million people (one in ten) will experience severe hearing loss (WHO, 2025).

Hearing loss affects not only an individual’s language and communication skills but also cognitive functions, academic performance, social relationships, and motor development. Untreated hearing loss in early life can lead to language delays, learning difficulties, and social adaptation problems in children. In adults, it can cause social isolation, reduced work productivity, and psychological issues such as depression. These adverse effects can be mitigated through medical interventions, communication therapies, special education programs, psychological counseling, and social support services (Ministry of Family and Social Services, ASPB, 2014).