Loudness and Pitch Perception using Dynamically Compensated Virtual Channels.

Loudness and Pitch Perception using Dynamically Compensated Virtual Channels.
Hear Res. 2016 Dec 07;:
Authors: Nogueira W, Litvak L, Landsberger DM, Büchner A
Abstract
Reducing power consumption is important for the development of smaller cochlear implant (CI) speech processors. Simultaneous electrode stimulation may improve power efficiency by minimizing the required current applied to a given electrode. Simultaneous in-phase stimulation on adjacent electrodes (i.e. virtual channels) can be used to elicit pitch percepts intermediate to the ones provided by each of the physical electrodes in isolation. Virtual channels are typically implemented in monopolar stimulation mode, producing broad excitation patterns. Focused stimulation may reduce the excitation patterns, but is inefficient in terms of power consumption. To create a more power efficient virtual channel, we developed the Dynamically Compensated Virtual Channel (DC-VC) using four adjacent electrodes. The two central electrodes are current steered using the coefficient α (0<α<1 ) whereas the two flanking electrodes are used to focus/unfocus the stimulation with the coefficient σ (-1<σ<1). With increasing values of σ, power can be saved at the potential expense of generating broader electric fields. Additionally, reshaping the electric fields might also alter place pitch coding. The goal of the present study is to investigate the tradeoff between place pitch ...

Source: Hearing Research - December 6, 2016 Category: Audiology Authors: Nogueira W, Litvak L, Landsberger DM, Büchner A Tags: Hear Res Source Type: research