title: Auditory steady state responses and cochlear implants: Modeling the artifact-response mixture in the perspective of denoising.
abstract: Auditory steady state responses (ASSRs) in cochlear implant (CI) patients are contaminated by the spread of a continuous CI electrical stimulation artifact. The aim of this work was to model the electrophysiological mixture of the CI artifact and the corresponding evoked potentials on scalp electrodes in order to evaluate the performance of denoising algorithms in eliminating the CI artifact in a controlled environment. The basis of the proposed computational framework is a neural mass model representing the nodes of the auditory pathways. Six main contributors to auditory evoked potentials from the cochlear level and up to the auditory cortex were taken into consideration. The simulated dynamics were then projected into a 3-layer realistic head model. 32-channel scalp recordings of the CI artifact-response were then generated by solving the electromagnetic forward problem. As an application, the framework's simulated 32-channel datasets were used to compare the performance of 4 commonly used Independent Component Analysis (ICA) algorithms: infomax, extended infomax, jade and fastICA in eliminating the CI artifact. As expected, two major components were detectable in the simulated datasets, a low frequency component at the modulation frequency and a pulsatile high frequency component related to the stimulation frequency. The first can be attributed to the phase-locked ASSR and the second to the stimulation artifact. Among the ICA algorithms tested, simulations showed that infomax was the most efficient and reliable in denoising the CI artifact-response mixture. Denoising algorithms can induce undesirable deformation of the signal of interest in real CI patient recordings. The proposed framework is a valuable tool for evaluating these algorithms in a controllable environment ahead of experimental or clinical applications.
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.|Lyon Neuroscience Research Center (Inserm U1028 CNRS UMR5292), Lyon, France.|Department of Audiology and Otoneurological Evaluation, Civil Hospitals of Lyon, Lyon, France.
authors.forename: Faten
authors.initials: F
authors.lastname: Mina
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.|Lyon Neuroscience Research Center (Inserm U1028 CNRS UMR5292), Lyon, France.|Department of Audiology and Otoneurological Evaluation, Civil Hospitals of Lyon, Lyon, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Attina
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Duroc
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.|Lyon Neuroscience Research Center (Inserm U1028 CNRS UMR5292), Lyon, France.|Department of Audiology and Otoneurological Evaluation, Civil Hospitals of Lyon, Lyon, France.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Veuillet
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.|Lyon Neuroscience Research Center (Inserm U1028 CNRS UMR5292), Lyon, France.|ENT Department, Civil Hospitals of Lyon, Lyon, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Truy
authors.affiliation: Claude Bernard Lyon 1 University, Lyon, France.|Lyon Neuroscience Research Center (Inserm U1028 CNRS UMR5292), Lyon, France.|Department of Audiology and Otoneurological Evaluation, Civil Hospitals of Lyon, Lyon, France.
authors.forename: Hung
authors.initials: H
authors.lastname: Thai-Van
mesh_terms: D000161:Acoustic Stimulation; D000465:Algorithms; D000704:Analysis of Variance; D016477:Artifacts; D001303:Auditory Cortex / Q000503:physiopathology*; D001306:Auditory Pathways / Q000503:physiopathology; D019929:Cochlear Implantation; D003054:Cochlear Implants / Q000592:standards*; D019295:Computational Biology / Q000379:methods; D003198:Computer Simulation; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D034381:Hearing Loss / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D008959:Models, Neurological