Skip to main content
padlock icon - secure page this page is secure

Effectiveness of Directional Microphones in Bilateral/Bimodal Cochlear Implant Users—Impact of Spatial and Temporal Noise Characteristics

Buy Article:

$52.00 + tax (Refund Policy)


To measure speech reception thresholds (SRTs) in co-located (S0N0) and diffuse noise conditions (multi-source noise field, MSNF) and to assess the impact of beamforming algorithms in MSNF in cochlear implant (CI) users.

Study Design:

Non-randomized, open, prospective study.


Tertiary referral cochlear implantation center.Patients:

Participants included 14 CI users (7 bimodal, 7 bilateral) and 14 normal hearing young adults.


Cochlear implantation.

Main Outcome Measures:

SRTs were assessed by means of a German matrix sentence test in either continuous or modulated noise. Loudspeakers were configured in two different conditions: S0N0 and MSNF (speech source in front, four speakers distributed at ±28.6 and ±151.4 degrees). In MSNF, the CI speech processor microphone was set in different directional sensitivity settings: standard (sub-cardioid), fixed (super-cardioid), and adaptive.Results:

In continuous noise, SRTs of both CI groups were comparable. In modulated noise, bimodal CI users showed lower SRTs than bilateral CI group, but significant benefit from glimpsing was only demonstrated in normal hearing participants. All subject groups showed significant spatial release from masking (i.e., SRT improvement in MSNF compared with S0N0 condition) in continuous noise. A tendency of improved SRT (1 dB bimodal, 2 dB bilateral) with fixed and adaptive directional sensitivity was found which could not be statistically confirmed due to large between-subject variations.

The absence of the glimpsing effect in CI users was reaffirmed in the present study. Although very effective in single noise source conditions, the beneficial impact of beamforming algorithms in multiple noise source conditions is poor.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
No Metrics

Keywords: Cochlear implant; Hearing aids; Multisource noise field; Speech perception

Document Type: Research Article

Affiliations: Audiological Acoustics, ENT Department, University Hospital Frankfurt, Frankfurt am Main, Germany

Publication date: December 1, 2017

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more