Measurement of temporal interaction due to neural dynamics with cochlear implants.

In cochlear implants (neuroprosthesis for deaf) the auditory nerve is stimulated directly by electrical pulses. The general shortcoming of electrical stimulation is field spread and results in channel interaction. The independent information transmission to the brain is limited as the channels are not well separated which leads to poor frequency resolution and impaired speech understanding in noise. In this context the trend to encode auditory signals by low numbers of frequency channels but high stimulation pulse-rates arises the question: how good is the temporal resolution?To determine temporal interaction of electrical stimulation in humans, we measured the influence of a sub-threshold pre-pulse with fixed charge on the perception threshold of a subsequent probe pulse. The inter pulse distance IPD between pre-pulse and probe varied between 20?s to 20 ms to evaluate temporal interaction. The fixed charge of the pre-pulse was 80     «

In cochlear implants (neuroprosthesis for deaf) the auditory nerve is stimulated directly by electrical pulses. The general shortcoming of electrical stimulation is field spread and results in channel interaction. The independent information transmission to the brain is limited as the channels are not well separated which leads to poor frequency resolution and impaired speech understanding in noise. In this context the trend to encode auditory signals by low numbers of frequency channels but hig...     »