Abstract:
Manipulation of cochlear implant (CI) place pitch was carried out with current steering by stimulating two CI
electrodes sequentially. The objective was to investigate whether shifts in activated neural populations could be
achieved to produce salient pitch differences and to determine which stimulation parameters would be more
effective in steering of current. These were the pulse rate and pulse width of electrical stimuli and the distance
between the two current-steering electrodes. Nine CI users participated, and ten ears were tested. The pattern of pitch
changes was not consistent across listeners, but the data suggest that individualized selection of stimulation parameters
may be used to effect place pitch changes with sequential current steering. Individual analyses showed that pulse
width generally had little influence on the effectiveness of current steering with sequential stimuli, while more
salient place pitch shifts were often achieved at wider electrode spacing or when the stimulation pulse rate was the
same as that indicated on the clinical MAP (the set of stimulation parameters) of the listener. Results imply that current
steering may be used in CIs that allow only sequential stimulation to achieve place pitch manipulation.
