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microphones are muted. Voice activity steers the switching
between microphones, which occurs automatically and
quickly on a first come, first-served basis.
For conditions two and three, the listener was wearing
the Naı́da speech processor connected to a Roger 17 re-
ceiver (Fig. 2).
For the ‘‘1 pen’’ condition, a single Roger Pen trans-
mitter was placed in the middle of the table. For the ‘‘3
pens’’ condition, each of the three talkers was equipped
with a Roger Pen transmitter that was placed in front of
each of the three loudspeakers at approximately 20 cm, at a
necktie position relative to the speaker (Fig. 3).
All subjects had been fitted with the HiRes Optima
(Sequential) sound processing strategy and an input dy-
namic range of 80 dB on their everyday processors. Pro-
gram parameters were set according to the FOX target
driven, computer-assisted approach described in Govaerts
et al. [14, 15, 16].
For this study, each subject was provided with a new
Naı́da CI Q70 CI processor for the purposes of testing only
without any program changes. The Roger 17 receiver was
connected to the processor through the Naı́da Powercel 170
auxiliary input. In the ‘‘no pen’’ condition, the CI re-
cipient’s current ‘‘daily’’ program and microphone option
were used. This microphone option could either be the
T-mic or processor mic dependent on his/her preference
. For the ‘‘1 pen’’ and ‘‘3 pens’’ conditions, this ‘‘daily’’
program was modified by changing the signal input from
100 % microphone input to a 50:50 mix of the recipient’s
current microphone option and Roger 17 on the aux input,
as recommended by Wolfe and Schafer  and Advanced
Roger automatically adjusted the gain depending on the
noise level. In the ‘‘3 pens’’ condition, the Roger Pens all
automatically worked in a beam-forming microphone
mode. In the ‘‘1 pen’’ condition, with the Roger Pen lying
horizontally on a table, the Roger Pen automatically se-
lected an omnidirectional microphone mode for noise
levels below 70 dB SPL. At higher ambient noise levels,
the Roger Pen automatically switched to beam forming.
Built-in hysteresis prevents frequent switching between
omnidirectional and beam forming when the noise level
hovers around 70 dB SPL.
Seven of the twelve subjects wore only one implant. The
five bimodal users (CI ? contralateral hearing aid) were
instructed to take their hearing aid off during the testing.
There was no bilateral Naı́da CI Q70 user included in the
Speech perception was tested using the Flemish sentences-
in-noise test [18, 19]. This test consists of 36 lists of 10
sentences each, characterized by a varying number of tar-
get words. Scores were recorded as the percentage of the
target words correctly repeated by the listener.
Individual sentences were presented randomly from one
of the three Talker loudspeakers for each sentence in the
list. The presentation level of the speech was fixed at 65 dB
SPL measured at the listener’s head for each speaker in-
dividually. Multi-talker babble noise  was presented
through the Noise speakers at fixed levels of 55, 60, 65, 70,
75, and 80 dB SPL. Hence, all listeners were tested in three
conditions and at six different SNRs per condition. The
order of conditions was randomized, and subjects were not
aware of the testing condition (single-blinded trial).
The speech reception threshold (SRT) was calculated
(by linear interpolation) as the SNR at which a 50 % score
was obtained. The SRT constituted the primary study
outcome, while the word score at each SNR was also
computed and provided the secondary outcome measure.
Descriptive statistics were computed for SRT results and
percent correct word scores. A normality test (Shapiro–
Wilks) was run to decide if a parametric or non-parametric
repeated ANOVA should be conducted to compare SRT in
the three conditions. The secondary outcome measures
were assessed by means of a two-way ANOVA with two
repeated factors (SNR and condition). For each repeated
ANOVA analysis, the sphericity assumption (equal sub-
populations variances) was tested using Maulchy’s test,
which led to run a correction for multivariate effects when
necessary (Greenhouse-Geisser correction). Results were
Fig. 2 User wearing a Naida CI Q70 connected with the integrated
Roger 17 receiver. The Roger 17 receiver is connected by sliding it
over the bottom of the PowerCel 170 battery pack
Eur Arch Otorhinolaryngol
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