Developments to Watch
HEARING AIDS THAT KNOW WHAT YOU WANT TO HEAR
As America's baby boomers age, tomorrow's seniors may be more prone to hearing loss. That's because rock music often booms loudly enough to gradually but permanently damage hearing. So Michael Hoffman, an assistant professor of electrical engineering at the University of Nebraska in Lincoln, figured it was time for a better hearing aid.
The problem with most hearing aids is that they don't discriminate between the sounds that wearers want to hear and those they don't. So the voice of someone sitting across the table in a crowded restaurant gets drowned out by the surrounding cacophony. Hoffman's solution: make the hearing aid more directional--most sensitive to sounds coming from straight ahead. He found the key in the digital signal-processing (DSP) chips that plot the direction of blips in radar and sonar systems. While his prototype works, Hoffman says it will take late-1990s DSP chips to shrink it down to in-the-ear size. Using today's chips, it would be the size of a Walkman.EDITED BY OTIS PORT