Influence of Interactions Between Virtual Channels in Cochlear Implants: Biological Stimulation Using Current Source Method

Cochlear implants are devices which are surgically inserted into the internal ear, partially restoring hearing to people with profound deafness. Alternatives to improve levels of auditory perception are to increase the number of channels or frequency bands, that would need to increase the number of electrodes or electrode pairs per channel. Monopolar Virtual Channel (MPVC) stimulation mode increases the number of channels without increasing the number of electrodes using current steering. With this stimulation mode what still happens is interaction between the virtual channels, so some people who have these implants have not reported a striking improvement. In the present work, parameters of this electrical stimulation mode are modeled and evaluated. The results suggested that the maximal stimulation current can be determined so that no electrical interaction will occur between adjacent channels. If the stimulation current is higher than the calculated value, electrical interactions will occur between adjacent channels.