IHS Assistive Listening Devices and Hearing Assistive Technology

Question 1

An FM (frequency modulation) assistive listening system improves hearing in noisy environments primarily by:

Accepted Answer

Transmitting the speaker's voice wirelessly directly to the listener's receiver, bypassing background noise

Answer

FM systems use a microphone worn by or near the speaker (e.g., a teacher or spouse) that wirelessly transmits the voice signal directly to the listener's receiver or hearing aid. Because the signal bypasses the room's noise and distance, the listener receives speech at a favorable signal-to-noise ratio regardless of background noise or room acoustics.

Question 2

A telecoil (T-coil) in a hearing aid is designed to:

Accepted Answer

Pick up electromagnetic signals from compatible telephones and hearing loop systems

Answer

A telecoil is an induction coil inside a hearing aid that picks up electromagnetic signals generated by hearing loop (induction loop) systems and compatible telephones marked with the 'T' symbol. It provides a direct electromagnetic signal path that bypasses the hearing aid's microphone, reducing background noise. Bluetooth is a separate wireless technology; telecoils predate it.

Question 3

Which assistive listening system is most commonly installed in theaters, houses of worship, and conference rooms to benefit hearing aid users with telecoils?

Accepted Answer

Hearing loop (audio induction loop) system

Answer

Hearing loop (induction loop) systems use a wire loop installed around a room's perimeter to transmit magnetic signals from the venue's audio system directly to hearing aids with active telecoils. They are widely used in public venues because they require no receiver equipment — users simply switch to the T-coil setting. IR systems also work in venues but require a receiver; FM systems are more commonly portable.

Question 4

A patient with severe hearing loss asks about devices that can alert them to sounds in their home environment, such as a doorbell or fire alarm. The specialist should recommend:

Accepted Answer

Alerting and signaling assistive listening devices that use visual (flashing lights) or vibrotactile alerts

Answer

Alerting and signaling devices (visual alerting systems) use flashing lights, vibrating pagers, or bed shakers to notify individuals with hearing loss of environmental sounds like doorbells, telephone rings, baby cries, smoke alarms, or alarm clocks. These are an important category of hearing assistive technology (HAT) for people with severe-to-profound loss who may not benefit sufficiently from amplification alone.

Question 5

Bluetooth-enabled hearing aids paired with a smartphone allow the user to:

Accepted Answer

Stream audio from the phone and control hearing aid settings via a companion app

Answer

Modern Made-for-Smartphone (MFi for iOS, ASHA for Android) Bluetooth hearing aids allow direct audio streaming from phones (calls, music, navigation) while typically keeping the microphone active as well (though some modes can prioritize streamed audio). Companion apps also allow the user to adjust volume, programs, and settings remotely. Bluetooth does not replace telecoils in loop-equipped public venues.

IHS - International Hearing Society Practice Test

IHS - International Hearing Society Practice Test

IHS Assistive Listening Devices and Hearing Assistive Technology