The Cochlear Implant EEG Artifact Recorded From an Artificial Brain for Complex Acoustic Stimuli.

Abstract

We created a brain substitute using agar that simulates the brain's conductivity, placed it in a human skull, and performed EEG recordings with CIs from three different manufacturers. As stimuli, we used simple and complex non-speech stimuli, as well as naturally produced continuous speech. We examined the effect of manipulating device settings in both controlled experimental CI configurations and real clinical maps. An increase in the magnitude of the stimulation current through the device settings increases also the magnitude of the artifact. The artifact recorded to speech is smaller in magnitude than for non-speech stimuli due to signal-inherent amplitude modulations. The CI EEG artifact for speech appears more difficult to detect than for simple stimuli. Since the artifact differs across CI users, due to their individual clinical maps, the method presented enables insight into the individual manifestations of the artifact.