Reduction in excitability of the auditory nerve following acute electrical stimulation at high stimulus rates: III. Capacitive versus non-capacitive coupling of the stimulating electrodes

摘要: Abstract Safe electrical stimulation of neural tissue is typically achieved using charge-balanced biphasic current pulses, which are designed to minimize the generation direct (DC) and production harmful electrochemical products. However, due kinetics charge injection process, stimulators must also use capacitive coupling or electrode shorting techniques, ensure DC levels minimal. Previous studies have reported a reduction in excitability auditory nerve following acute simulation at high rates intensities. Elevated were these despite pulses shorting. The present study was investigate extent contributed stimulus induced reductions excitability. Adult guinea pigs bilaterally implanted unilaterally stimulated for two hours 200, 400 1000 pulses/s (pps) intensity well above clinical (0.34 μC/phase). controlled either shorting, with coupling. Electrically evoked brainstem responses (EABRs) recorded before periodically stimulation. It found that EABR amplitude function rate. While there little change 200 pps, significant post-stimulus observed pps during three hour monitoring period. Stimulation capacitively coupled electrodes, eliminated all DCs, showed amplitudes similar those alone. no difference versus ( P >0.05) >0.05), 2.5 μA) can contribute changes. although statistically significant, effects very small compared rate, per se.