Effects of electrical pulse polarity shape on intra cochlear neural responses in humans: Triphasic pulses with cathodic second phase.

Effects of electrical pulse polarity shape on intra cochlear neural responses in humans: Triphasic pulses with cathodic second phase.
Hear Res. 2013 Oct 23;
Authors: Bahmer A, Baumann U
Abstract
To avoid a continuous charging of the stimulated tissue in auditory prostheses, charge-balanced pulses are used. In this context the effect of electrical pulse shape and polarity is still a matter of debate and the most effective pulse shape needs to be determined (Bahmer et al., 2010a; Undurraga et al., 2010; Wieringen et al., 2008; Macherey et al., 2008). Therefore, we conducted electrophysiological measurements, namely electrical compound action potentials (ECAPs) to assess response strength elicited by various pulse shapes and polarities in five cochlear implant recipients (SonataTI100/PulsarCI100 devices, MED-EL Innsbruck). ECAP response strength depending on pulse shape was compared with individual psychophysical thresholds. Results indicated the weakest response amplitude and highest thresholds for symmetric triphasic pulse shapes (with cathodic second phase), and the strongest response amplitude and lowest thresholds for biphasic pulses with anodic first phase. Biphasic pulses with cathodic first phase generated intermediate response amplitude and thresholds.
PMID: 24161948 [PubMed - as supplied by publisher]

Source: Hearing Research - October 23, 2013 Category: Audiology Authors: Bahmer A, Baumann U Tags: Hear Res Source Type: research