FM Systems and Nucleus® Cochlear™ Implants - For professionals ...

esults showed asc did not degrade speech recognition in quiet relative to performance with asc off. at the two highest
noise conditions (70/63, 74/70), asc significantly improved performance when compared to asc off. to summarize, asc improves
speech recognition in noise, not only for FM use but also for signals arriving at the sound processor microphone when the
FM microphone is muted.
this finding highlights the recommendation that asc should be used in noisy listening situations when an FM system is not available
as well as when FM is used. cochlear recommends using the everyday program default of ASc+ADRo with FM systems.
important parameters
With the introduction of custom sound suite 3.1 and euro accessory adaptor for the cochlear nucleus ® 5 sound processor,
there are updated recommendations for programming parameters, as summarized in the tables below.
PARAMETER RECOMMENDATION
Mixing ratio 1:1
Auto Telecoil off
note: for neckloop receivers, please activate the telecoil
SmartSound environment asc+aDro (use default everyday environment setting and the default sensitivity setting of 12)
PARAMETER JUSTIFICATION
Mixing ratio a mixing ratio of 1:1 in a classroom environment provides a good compromise between FM inputs
(teacher) and the sound processor microphone inputs (other students in the room). other mixing
ratios may be used as desired to reduce audibility of sounds coming directly into the nucleus sound
processor microphones, however 1:1 is strongly recommended for classroom use, meetings, etc.
Auto Telecoil cochlear recommends deactivating auto telecoil for children. this is especially true with
FM systems because:
• the first sentence spoken by the teacher after a long pause may not be picked up by the FM.
(this is because it can take a few seconds for the auto telecoil to recognize the incoming speech.)
• music is not likely to activate the auto telecoil. (This is because the auto telecoil signal may drop
out when non-speech-like signals are present.)
SmartSound environment asc is designed to automatically reduce the sound processor’s microphone sensitivity to reduce
the negative effects of background noise and is proven to provide optimal performance when
using FM. asc should always be used with FM. 3
References:
aDro ® actively adjusts individual channel gains. it increases the gains for soft sounds and
decreases the gains for high intensity sounds.
1 american academy of audiology clinical practice guidelines. remote Microphone assistance technologies for children and youth from
Birth to 21 years. april 2008. http://www.audiology.org/resources/documentlibrary/Documents/hatguideline.pdf
2 pearsons, K., Bennett, r., and Fidel. (1977). speech levels in various noise environments. project report on contract 68 01-2466.
Washington, Dc, Us environmental protection agency.
3 Wolfe J, schafer e, heldner B, Mulder h, Ward e, Vincent B. evaluation of speech recognition in noise with cochlear implants and
dynamic FM. Journal of the american academy of audiology. 2009;20:409-421.
This is the cochlear promise to you. As the global leader in hearing
solutions, Cochlear is dedicated to bringing the gift of sound to people all
over the world. With our hearing solutions, Cochlear has reconnected over
230,000 cochlear implant and Baha ® recipients to their families, friends
and communities in more than 100 countries.
Along with the industry’s largest investment in research and development,
we continue to partner with leading international researchers and hearing
professionals, ensuring that we are at the forefront in the science of hearing.
For the person with hearing loss receiving any one of the Cochlear hearing
solutions, our commitment is that for the rest of your life we will be here
to support you. hear now. And always
as your partner in hearing for life, cochlear believes it is important that you understand not
only the benefits, but also the potential risks associated with any cochlear implant.
you should talk to your hearing health care provider about who is a candidate for cochlear
implantation. Before any cochlear implant surgery, it is important to talk to your doctor about
cDc guidelines for pre-surgical vaccinations. cochlear implants are contraindicated for patients
with lesions of the auditory nerve, active ear infections or active disease of the middle ear.
cochlear implantation is a surgical procedure, and carries with it the risks typical for surgery.
you may lose residual hearing in the implanted ear. electrical stimulation may result in some side
effects, including ringing in the ear, stimulation of the facial nerve; in rare cases this may cause
pain. though rare, it is possible that additional surgery may be required at some point to resolve
complications with a cochlear implant.
For complete information about risks and benefits of cochlear implantation, please refer to the
nucleus package insert (available at www.cochlearAmericas.com/nucleusindications).
For further information please contact your local cochlear representative or
visit us on the web at: www.cochlearAmericas.com
cochlear Americas
13059 east peakview avenue
centennial, co 80111 Usa
Cochlear, the elliptical logo, SmartSound, Freedom, ESPrit and Custom Sound are trademarks of Cochlear
Limited. Nucleus and Adro are registered trademarks of Cochlear Limited. Baha is a registered trademark of
Cochlear Bone Anchored Solutions AB, a Cochlear Group Company. © Cochlear Limited 2011
FUN1276 ISS2 JAN11
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Technology SpoTlighT
INFORMATIONAL seRIes FOR pROFessIONALs
FM Systems and Nucleus ®
Cochlear Implants
FM systems are designed to improve a cochlear implant recipient’s signal-to-noise ratio (snr)
to allow him/her to hear better in noisy environments, reverberant places and to hear speech
from a distance. the microphone of the FM transmitter picks up the speaker’s voice and sends
it via a radio frequency (rF) channel to the FM receiver. FM systems have been used for quite
some time by cochlear implant recipients and hearing aid users. as FM technology improves
more cochlear implant recipients are using FM systems. recently, cochlear introduced a
new euro accessory adaptor and a new version of software, custom sound suite 3.2. in
conjunction with the new products, cochlear has updated programming recommendations
for the cochlear nucleus 5 cp810 sound processor when using an FM system.
considerations for FM Use
cochlear recommends the following items be addressed prior to fitting a cochlear implant
recipient with an FM system.
It is very important that the recipient has the ability to provide feedback regarding
what he or she hears when the FM is connected to the sound processor
• Approximately 3-6 months of cochlear implant experience
Euro adaptor
• Adequate communication skills (oral or sign)
FM receiver
• Reliable responses to developmentally-appropriate auditory tasks
• Someone trained to perform a daily listening check and troubleshoot the FM equipment
• Choose a seat that allows best access to person wearing the transmitter while avoiding:
— sitting near large metallic objects
— sitting behind obstructions and directly under fluorescent lights
— When an FM cable is used, try to keep the FM cable as straight as possible
technology spotlight :: issUe 3 :: JanUary 2011 :: FM systeMs

ear-level FM receivers listening check clinical results using
When using an ear-level FM receiver and the transmitter and
receiver are turned on, a wireless connection is established
between the two devices. Most current devices will
automatically synchronize to the same channel.
the new euro accessory adaptor connects an ear-level
receiver to the cochlear nucleus ® 5 sound processor via
the accessory socket in three steps:
1. insert the FM receiver into the three pin socket on the
euro accessory adaptor
2. insert the euro accessory adaptor into the sound
processor’s accessory socket
3. switch on the FM receiver (the nucleus 5 sound
processor will automatically detect the euro accessory
adaptor and FM receiver when programmed with
custom sound suite 3.1 or higher)
neckloop systems
a neckloop consists of a covered wire that is physically
connected to an FM receiver. the neckloop and attached
receiver are worn around the neck. the sound processor’s
telecoil is used to pick up the electromagnetic field that
the neckloop produces. When the transmitter and receiver
are turned on, a wireless connection is established between
the two devices. Most current devices will automatically
synchronize to the same channel.
Bodyworn FM receivers
the bodyworn FM receiver is used in combination with
an FM transmitter and microphone. For cochlear implant
recipients using this type of receiver, a cable is used to
connect the nucleus 5 sound processor to the receiver.
the Freedom accessory adaptor is needed to connect
the processor end of the esprit FM cable into the
accessory socket of the sound processor.
technology spotlight :: issUe 3 :: JanUary 2011 :: FM systeMs
one way to verify proper functioning is by using the monitor
earphones to do a listening check of the FM system. the
monitor earphones will allow you to listen to the signal from
the FM system to ensure it sounds satisfactory. this can be
accomplished in five steps:
1. insert the monitor earphones into the accessory socket
of the processor
2. ensure your FM receiver and connecting device (euro
accessory adaptor or the Freedom accessory adaptor used
with an FM cable) are joined together
3. turn the FM receiver and transmitter on
4. insert the euro accessory adaptor (with FM receiver
attached) into the socket on the monitor earphones. if you
are not using an ear-level FM system you will need to use
the Freedom accessory adaptor with the esprit FM cable
** It is important to plug the Monitor Earphones into the
Accessory Socket before you connect the adaptor and FM
receiver to the Monitor Earphones. This will ensure that the
accessory is recognized by the Monitor Earphones.
5. Use the Monitor earphones to listen to the signal from the
FM system
performing an informal listening check with and without FM
in quiet and noise at some distance e.g., 6 feet in quiet and in
noise is also recommended.
• Have recipient repeat (or action): Ling Sounds (ah, oo, ee,
sh, ss, mm), count numbers, count number of syllables
in word, indicate long or short sounds or follow simple
instructions: e.g. clap your hands.
confirmation of FM benefit
as with any hearing aid fitting or cochlear implant
programming, a verification check to ensure benefit and proper
functioning of the FM system is recommended. Verification
checks are particularly important for children, who may not
always be able to provide accurate feedback regarding sound
quality and benefit from an FM system.
a brief review of testing for FM benefit is included with this
piece, but more detailed information on test recommendations
and guidelines can be found in the american academy of
audiology clinical practice guidelines document on remote
Microphone hearing assistance technologies for children and
youth from Birth to 21 years. 1
one way to verify the benefit from an FM system is to
complete testing in a sound booth. Verification testing in a
sound booth should include testing in four conditions:
• Speech recognition testing in quiet without FM
• Speech recognition testing in quiet with FM
• Speech recognition testing in noise without FM
• Speech recognition testing in noise with FM
please note that the recommended speech level for each
scenario is 50 dB hl (65 dB spl) to represent the teacher’s
voice at a listening distance of 2 meters. 2 a variety of
presentation levels could be considered to represent different
listening distances, such as 55 dB hl (70 dB spl) to represent
the teacher’s voice at 1 meter, or 40 dB hl (55 dB spl) to
represent conversational levels of speech from 2 meters.
to maintain a realistic test setting, speech and noise should
not be presented from the same loudspeaker as this is not
representative of a typical classroom environment where the
FM microphone is near the teacher’s mouth and the noise is
typically diffuse.
scenario 1: speech recognition testing in quiet without FM
• FM receiver not attached to sound processor
• Speech presented at 65 dB SPL (to represent typical level
of teacher’s voice in a classroom setting)
FM ReMoveD
Speech – 65 dB SPL
scenario 2: speech recognition testing in quiet with FM
• Activate FM transmitter microphone and turn on FM receiver
• Student remains in same test position
• Evaluate speech recognition performance with transmitter
microphone on and placed next to speaker (typically
hung 6 inches from speaker)
• Speech presented at 65 dB SPL
FM on
Speech – 65 dB SPL
Speech
180 DegRee plAceMenT
Speech
180 DegRee plAceMenT
For additional information, please review the american
academy of audiology clinical practice guidelines for remote
Microphone hearing assistance technologies for children and
youth from Birth to 21 years. 1
speech recognition performance using the FM system in noise
should offer a significant benefit over using the sound processor
alone in noise. ideally, speech recognition testing results using the
FM system in noise should be close to the results when tested in
quiet. speech recognition performance is tested in quiet with and
without the FM to confirm the FM system is working properly
and is not interfering with performance. also, if tested at a low
presentation level the FM performance should be better.
scenario 3: speech recognition testing in noise without FM
• FM transmitter microphone on mute or off, FM receiver
not attached to sound processor
• Speech presented at 65 dB SPL
• Noise presented at 65 dB SPL to represent a 0 dB SNR
(can be adjusted by changing presentation levels)
FM ReMoveD
Speech – 65 dB SPL
Noise – 65 dB SPL
SNR – 0 dB SPL
noiSe
scenario 4: speech recognition testing in noise with FM
• Activate FM transmitter microphone and turn on FM receiver
• Student remains in same test position
• Evaluate speech recognition performance with transmitter
microphone on and placed next to speaker (typically hung
6 inches from speaker)
• Speech presented at 65 dB SPL
• Noise presented at 65 dB SPL to represent a 0 dB SNR
(can be adjusted by changing presentation levels)
FM on
Speech – 65 dB SPL
noise – 65 dB SPL
SnR – 0 dB SPL
NOISE
Speech
180 DegRee plAceMenT
Speech
180 DegRee plAceMenT
smartsound
with FM systems
the new smartsound everyday default of asc+aDro is
advantageous when using FM systems. Wolfe and colleagues
(2009) examined the effects of using asc, i.e. comparison
of asc on versus asc off. eleven adult subjects listened to
speech in noise with their Freedom sound processor while
using either traditional FM or the dynamic FM system, inspiro,
available from phonak . it should be noted that some, but not
all of these subjects used aDro in their everyday Map that
was used in the FM evaluation. stimuli consisted of two lists of
hint sentences for each condition. sentences were presented
at 85 dBa at the location of the FM transmitter microphone,
and 60 dBa at the location of the cochlear implant sound
processor microphone. the competing classroom noise was
presented from four loudspeakers located in the four corners of
the classroom. speech recognition in noise was evaluated with
each FM system * (phonak Mlxs traditional FM receiver and the
phonak dynamic FM receiver) at three noise levels — 65 dBa,
70 dBa, and 75 dBa. For a given noise level, the same intensity
was presented at the location of the FM transmitter as at the
location of the sound processor microphones.
analysis of variance revealed significant main effects of
FM system, noise level and asc condition. clearly, using
asc improved performance across noise levels and with
both traditional and dynamic FM systems.
While the main objective of an FM system is to improve the
signal-to-noise ratio (snr) of the primary talker, it is also
important that environmental sounds and speech from the
sound processor’s microphone are audible to the user of the
FM system. this is especially important during meetings and
discussion sessions, such as in a classroom, when the user of
the FM must hear and understand many speakers in order to
effectively participate in the conversation.
to determine if asc would negatively affect speech
recognition through the environmental microphone of the
sound processor, Wolfe and colleagues (2009) compared
speech recognition with asc on and off when speech
was presented to the Freedom sound processor. in these
conditions, the Dynamic FM system remained active, but
the FM microphone was muted. the following conditions
were evaluated with asc on and off:
1. in quiet with a presentation level of 60 dBa
2. in noise with speech fixed at 65 dBa and noise fixed
at 55 dBa (65/55)
3. in noise with speech fixed at 70 dBa and noise fixed
at 63 dBa (70/63)
4. in noise with speech fixed at 74 dBa and noise fixed
at 70 dBa (74/70)
Percent correct
100
90
80
70
60
50
40
30
20
10
0
85%
65
10%
Dynamic FM
81%
5%
Noise Level (dBA)
48%
ASC On
70 75
ASC Off
Figure 1: Mean speech recognition in noise with asc on versus
asc off when subjects were listening using dynamic FM
Percent correct
100
90
80
70
60
50
40
30
20
10
0
70%
6%
Traditional FM
53%
0%
Noise Level (dBA)
28%
65 70 75
0%
ASC On
ASC Off
Figure 2: in contrast, mean performance using traditional FM
in the asc on versus asc off listening conditions
* Custom Sound 3.2 provides the capacity to use dynamic ear-level FM receivers.
0%