27th September 2020 is World Deaf Day, and this day is celebrated every year to inform and educate the general public, policymakers, healthcare professionals, and even family members of patients with hearing loss about the multiple implications of deafness. Awareness is also spread about the ways in which hearing can be corrected or aided. Assistive Listening Devices (ALDs) are suitable for varying degrees of deafness, and they can be used with any cochlear implant or hearing aid. The most common ALDs are—
Hearing Loop Systems - This system includes four parts—a sound source, an amplifier, a loop of wire branching out in the room, and a receiver that is worn as a headset or placed near the ear. Electromagnetic fields are used by the loops for delivering sound and the receiver picks up this sound directly. Alternately known as induction loop system, this ALD can be connected with a television set, an audio source, and even with public address systems. With a portable loop system, hearing loss may be alleviated for those who wish to be active in different listening environments.
Infrared Systems - Utilizing infrared light for transmission of sound, these ALDs convert sound into light signals following which, a beam is sent to the receiver worn by the listener. This infrared signal is then decoded back to sound by the receiver. Since these signals don’t pass through walls, Infrared Systems are especially convenient in places where the problem of competing signals might make hearing difficult. A shortcoming of this system, however, is that it cannot be used in places that have excess and multiple light sources.
FM Systems - These ALDs use radio signals for transmitting sounds and amplifying them as well. In classroom settings, FM systems are used wherein the instructor may wear a small microphone that is linked to a transmitter, and students who wear receivers set to the requisite channel or frequency can pick up the signals. FM systems are capable of transmitting signals up to nearly 300 feet, owing to which they can be used with ease in public places as well.
Alerting Devices - Listening devices such as doorbell alerts with flashing lights, vibrating alarm clocks, smoke detectors that flash and vibrate, etc. help to make your environment safer, especially when you choose not to wear hearing aids.
Adapting to an ALD can be life-changing for people with hearing impediments. Choice of ALDs is generally contingent on one’s specific requirements.