Head shadow, squelch, and summation effects with an energetic or informational masker in bilateral and bimodal CI users.
OBJECTIVE
The objective of the study was to investigate the influence of noise (energetic) and speech (energetic plus informational) maskers on the head shadow (HS), squelch (SQ), and binaural summation (SU) effect in bilateral and bimodal cochlear implant (CI) users.


METHODS
Speech recognition was measured in the presence of either a competing talker or modulated speech-shaped noise in 10 bimodal and 10 bilateral adult CI users. HS, SQ, and SU effects were calculated. The interfering signals were manipulated with respect to F0 to consider the influence of different speaker voices.


RESULTS
The effects HS, SQ, and SU differed depending on the type of masker. A detailed analysis of errors was used to dissociate energetic and informational masking effects. The analysis showed a release from energetic than from informational masking.


CONCLUSIONS
Noise interferers are not sufficient to reflect difficulties experienced with speech understanding in noise for bilateral and bimodal CI users.
Verena
V
Pyschny
Markus
M
Landwehr
Moritz
M
Hahn
Ruth
R
Lang-Roth
Martin
M
Walger
Hartmut
H
Meister
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001309:Auditory Threshold / Q000502:physiology; D003054:Cochlear Implants / Q000523:psychology*; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise; D010470:Perceptual Masking / Q000502:physiology*; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult