Research to Develop Ultrasonic Hearing Aid for Profoundly Deaf People

摘要

In 1948, ultrasonic waves were first found to be sensed by listening to bone conductance sounds, but both affirmative and negative reports have been made worldwide. Especially in 1991, words were discriminated by profoundly deaf people through bone conductance ultrasonic waves, which triggered heated arguments to refute this observation. However, both arguments lacked supporting objective data, so no decision was reached.