Biomedical Engineering Reference
In-Depth Information
hearing loss in many individuals will be
inevitable due to continued loud noise
exposure, age-related hearing loss, poor
health-related habits, and genetic deter-
minants. Hearing assistive and access
technologies may well benefit individuals
with hearing loss, but in many cases, they
have also benefited people with normal
hearing (e.g., telephone invented by A.
G. Bell and the acoustic modem invented
by R. H. Weitbrecht, J. C. Marsters, and
A. Saks). Likewise, individuals with hear-
ing loss may benefit from technologies
designed for the masses (e.g., electronic
and digital text messaging and e-mail), a
positive side effect.
This final chapter focuses not only
on new and soon-to-be-released tech-
nology, but also on some creative uses
of new or existing technology. Some
of these technologies have been intro-
duced in the preceding chapters, but we
bring them to the forefront again in this
chapter because they are so new, they
represent the current state of the art,
and they will shape the future. The first
part of this chapter touches on innova-
tion and creativity related to hearing aids
and implantable devices, such as remote
microphones. The remaining portion of
the chapter focuses on invention and cre-
ativity not specifically related to hearing
aids or implantable devices. With tech-
nology changing as rapidly as it does,
the information presented in this chapter
may soon be obsolete. Therefore, it is the
innovative application, as well as the inno-
vative technology, that may be gleaned
from this chapter with an eye toward the
future.
Technology Related to Hearing
Aids and Implantable Devices
Remote Microphones
One of the chief complaints from hearing
aid wearers has been listening and under-
standing in the presence of background
noise. With the use of remote micro-
phones such as Phonak's Roger Pen (see
Figure 4-10), as a hearing aid accessory,
noise between the speaker and the hear-
ing aid wearer can be greatly reduced. The
remote microphone is simply placed near
the speaker's mouth as he or she speaks
and the signal is transmitted directly to
the hearing aids. The speaker can hold the
remote microphone, clip it to an article
of clothing, or hang it on a loop around
the neck. Because the speaker's voice does
not have to travel through the air and suf-
fer the effects of the Inverse Square Law
(see Chapter 3), and will not be negatively
affected by either background noise or
reverberation, the signal-to-noise (SNR)
ratio is considerably better than hearing
aids alone, even with directional micro-
phones engaged on the hearing aids.
Digital Enhanced Cordless
Telecommunications
Telephones
Communicating over a telephone has
been quite a challenge for those with
hearing loss as no visual cues are pro-
vided and telephone filters limit the fre-
quency range available. Using a common
