Uncovering auditory evoked potentials from cochlear implant users with independent component analysis.

Auditory evoked potentials (AEPs) provide an objective measure of auditory cortical function, but AEPs from cochlear implant (CI) users are contaminated by an electrical artifact. Here, we investigated the effects of electrical artifact attenuation on AEP quality. The ability of independent component analysis (ICA) in attenuating the CI artifact while preserving the AEPs was evaluated. AEPs recovered from CI users were systematically correlated with age, demonstrating that individual differences were well preserved. CI users with high-quality AEPs were characterized by a significantly shorter duration of deafness. Finally, a simulation study revealed very high spatial correlations between original and recovered normal hearing AEPs (r>.95) that were previously contaminated with CI artifacts. The results confirm that after ICA, good quality AEPs can be recovered, facilitating the objective, noninvasive study of auditory cortex function in CI users.