Intracorporeal Cortical Telemetry as a Step to Automatic Closed-Loop EEG-Based CI Fitting: A Proof of Concept

Electrically evoked auditory potentials have been used to predict auditory thresholds in patients with a cochlear implant (CI). However, with exception of electrically evoked compound action potentials (eCAP), conventional extracorporeal EEG recording devices are still needed. Until now, built-in (intracorporeal) back-telemetry options are limited to eCAPs. Intracorporeal recording of auditory responses beyond the cochlea is still lacking. This study describes the feasibility of obtaining longer latency cortical responses by concatenating interleaved short recording time windows used for eCAP recordings. Extracochlear reference electrodes were dedicated to record cortical responses, while intracochlear electrodes were used for stimulation, enabling intracorporeal telemetry (i.e., without an EEG device) to assess higher cortical processing in CI recipients. Simultaneous extra- and intra-corporeal recordings showed that it is feasible to obtain intracorporeal slow vertex potentials with a CI similar to those obtained by conventional extracorporeal EEG recordings. Our data demonstrate a proof of concept of closed-loop intracorporeal auditory cortical response telemetry (ICT) with a cochlear implant device. This research breaks new ground for next generation CI devices to assess higher cortical neural processing based on acute or continuous EEG telemetry to enable individualized automatic and/or adaptive CI fitting with only a CI.

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Characterizing Cochlear Implant Artefact Removal from EEG Recordings Using a Real Human Model

MethodsX ◽

10.1016/j.mex.2021.101369 ◽

2021 ◽

pp. 101369

Author(s):

Jaime A. Undurraga ◽

Lindsey Van Yper ◽

Manohar Bance ◽

David McAlpine ◽

Deborah Vickers

Keyword(s):

Cochlear Implant ◽

Human Model ◽

Artefact Removal ◽

Eeg Recordings

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Auditory Speech Perception Development in Relation to Patient's Age with Cochlear Implant

International Archives of Otorhinolaryngology ◽

10.1055/s-0036-1584296 ◽

2016 ◽

Vol 21 (03) ◽

pp. 206-212 ◽

Cited By ~ 3

Author(s):

Grace Ciscare ◽

Erika Mantello ◽

Carla Fortunato-Queiroz ◽

Miguel Hyppolito ◽

Ana Reis

Keyword(s):

Speech Perception ◽

Cochlear Implant ◽

Cochlear Implants ◽

Statistical Difference ◽

Hearing Aid ◽

Age Groups ◽

Auditory Thresholds ◽

Caregiver Education ◽

Auditory Speech ◽

Hearing Aid Use

Introduction A cochlear implant in adolescent patients with pre-lingual deafness is still a debatable issue. Objective The objective of this study is to analyze and compare the development of auditory speech perception in children with pre-lingual auditory impairment submitted to cochlear implant, in different age groups in the first year after implantation. Method This is a retrospective study, documentary research, in which we analyzed 78 reports of children with severe bilateral sensorineural hearing loss, unilateral cochlear implant users of both sexes. They were divided into three groups: G1, 22 infants aged less than 42 months; G2, 28 infants aged between 43 to 83 months; and G3, 28 older than 84 months. We collected medical record data to characterize the patients, auditory thresholds with cochlear implants, assessment of speech perception, and auditory skills. Results There was no statistical difference in the association of the results among groups G1, G2, and G3 with sex, caregiver education level, city of residence, and speech perception level. There was a moderate correlation between age and hearing aid use time, age and cochlear implants use time. There was a strong correlation between age and the age cochlear implants was performed, hearing aid use time and age CI was performed. Conclusion There was no statistical difference in the speech perception in relation to the patient's age when cochlear implant was performed. There were statistically significant differences for the variables of auditory deprivation time between G3 - G1 and G2 - G1 and hearing aid use time between G3 - G2 and G3 - G1.

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Walking by Thinking: The Brainwaves Are Crucial, Not the Muscles!

Presence Teleoperators & Virtual Environments ◽

10.1162/pres.15.5.500 ◽

2006 ◽

Vol 15 (5) ◽

pp. 500-514 ◽

Cited By ~ 53

Author(s):

Robert Leeb ◽

Claudia Keinrath ◽

Doron Friedman ◽

Christoph Guger ◽

Reinhold Scherer ◽

...

Keyword(s):

Communication Channel ◽

Muscular Activity ◽

Proof Of Concept ◽

Closed Loop System ◽

Head Mounted Display ◽

Eeg Recordings ◽

Sensorimotor Rhythms ◽

Electroencephalogram Eeg ◽

Healthy Participants

Healthy participants are able to move forward within a virtual environment (VE) by the imagination of foot movement. This is achieved by using a brain-computer interface (BCI) that transforms thought-modulated electroencephalogram (EEG) recordings into a control signal. A BCI establishes a communication channel between the human brain and the computer. The basic principle of the Graz-BCI is the detection and classification of motor-imagery-related EEG patterns, whereby the dynamics of sensorimotor rhythms are analyzed. A BCI is a closed-loop system and information is visually fed back to the user about the success or failure of an intended movement imagination. Feedback can be realized in different ways, from a simple moving bar graph to navigation in VEs. The goals of this work are twofold: first, to show the influence of different feedback types on the same task, and second, to demonstrate that it is possible to move through a VE (e.g., a virtual street) without any muscular activity, using only the imagination of foot movement. In the presented work, data from BCI feedback displayed on a conventional monitor are compared with data from BCI feedback in VE experiments with a head-mounted display (HMD) and in a high immersive projection environment (Cave). Results of three participants are reported to demonstrate the proof-of-concept. The data indicate that the type of feedback has an influence on the task performance, but not on the BCI classification accuracy. The participants achieved their best performances viewing feedback in the Cave. Furthermore the VE feedback provided motivation for the subjects.

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Neural envelope tracking as a measure of speech understanding in cochlear implant users

10.1101/469643 ◽

2018 ◽

Author(s):

Eline Verschueren ◽

Ben Somers ◽

Tom Francart

Keyword(s):

Cochlear Implant ◽

Cochlear Implants ◽

Closed Loop ◽

Objective Measure ◽

Speech Understanding ◽

Envelope Tracking ◽

Actual Speech ◽

Speech Envelope ◽

Electroencephalogram Eeg ◽

Automatic Fitting

ABSTRACTThe speech envelope is essential for speech understanding and can be reconstructed from the electroencephalogram (EEG) recorded while listening to running speech. This so-called neural envelope tracking has been shown to relate to speech understanding in normal hearing listeners, but has barely been investigated in persons wearing cochlear implants (CI). We investigated the relation between speech understanding and neural envelope tracking in CI users.EEG was recorded in 8 CI users while they listened to a story. Speech understanding was varied by changing the intensity of the presented speech. The speech envelope was reconstructed from the EEG using a linear decoder and then correlated with the envelope of the speech stimulus as a measure of neural envelope tracking which was compared to actual speech understanding.This study showed that neural envelope tracking increased with increasing speech understanding in every participant. Furthermore behaviorally measured speech understanding was correlated with participant specific neural envelope tracking results indicating the potential of neural envelope tracking as an objective measure of speech understanding in CI users. This could enable objective and automatic fitting of CIs and pave the way towards closed-loop CIs that adjust continuously and automatically to individual CI users.

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P3 Cognitive Potential in Cochlear Implant Users

International Archives of Otorhinolaryngology ◽

10.1055/s-0037-1613687 ◽

2018 ◽

Vol 22 (04) ◽

pp. 408-414 ◽

Cited By ~ 2

Author(s):

Signe Grasel ◽

Mario Greters ◽

Maria Goffi-Gomez ◽

Roseli Bittar ◽

Raimar Weber ◽

...

Keyword(s):

Speech Recognition ◽

Cochlear Implant ◽

Auditory Processing ◽

Evoked Potential ◽

Control Group ◽

Central Auditory Processing ◽

Speech Discrimination ◽

Significant Difference ◽

Cortical Responses ◽

Peripheral Auditory System

Introduction The P3 cognitive evoked potential is recorded when a subject correctly identifies, evaluates and processes two different auditory stimuli. Objective to evaluate the latency and amplitude of the P3 evoked potential in 26 cochlear implant users with post-lingual deafness with good or poor speech recognition scores as compared with normal hearing subjects matched for age and educational level. Methods In this prospective cohort study, auditory cortical responses were recorded from 26 post-lingual deaf adult cochlear implant users (19 with good and 7 with poor speech recognition scores) and 26 control subjects. Results There was a significant difference in the P3 latency between cochlear implant users with poor speech recognition scores (G-) and their control group (CG) (p = 0.04), and between G- and cochlear implant users with good speech discrimination (G+) (p = 0.01). We found no significant difference in the P3 latency between the CG and G+. In this study, all G- patients had deafness due to meningitis, which suggests that higher auditory function was impaired too. Conclusion Post-lingual deaf adult cochlear implant users in the G- group had prolonged P3 latencies as compared with the CG and the cochlear implant users in the G+ group. The amplitudes were similar between patients and controls. All G- subjects were deaf due to meningitis. These findings suggest that meningitis may have deleterious effects not only on the peripheral auditory system but on the central auditory processing as well.

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Timing and Laminar Profile of Eye-Position Effects on Auditory Responses in Primate Auditory Cortex

Journal of Neurophysiology ◽

10.1152/jn.01228.2003 ◽

2004 ◽

Vol 92 (6) ◽

pp. 3522-3531 ◽

Cited By ~ 65

Author(s):

Kai-Ming G. Fu ◽

Ankoor S. Shah ◽

Monica N. O'Connell ◽

Tammy McGinnis ◽

Haftan Eckholdt ◽

...

Keyword(s):

Auditory Cortex ◽

Linear Array ◽

Current Source ◽

Eye Position ◽

Auditory Pathways ◽

Position Effects ◽

Auditory Responses ◽

Cortical Responses ◽

Auditory Response ◽

Laminar Current

We examined effects of eye position on auditory cortical responses in macaques. Laminar current-source density (CSD) and multiunit activity (MUA) profiles were sampled with linear array multielectrodes. Eye position significantly modulated auditory-evoked CSD amplitude in 24/29 penetrations (83%), across A1 and belt regions; 4/24 cases also showed significant MUA AM. Eye-position effects occurred mainly in the supragranular laminae and lagged the co-located auditory response by, on average, 38 ms. Effects in A1 and belt regions were indistinguishable in amplitude, laminar profile, and latency. The timing and laminar profile of the eye-position effects suggest that they are not combined with auditory signals at a subcortical stage of the lemniscal auditory pathways and simply “fed-forward” into cortex. Rather, these effects may be conveyed to auditory cortex by feedback projections from parietal or frontal cortices, or alternatively, they may be conveyed by nonclassical feedforward projections through auditory koniocellular (calbindin positive) neurons.

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Cortical Responses to Cochlear Implant Stimulation: Channel Interactions

Journal of the Association for Research in Otolaryngology ◽

10.1007/s10162-003-3057-7 ◽

2004 ◽

Vol 5 (1) ◽

pp. 32-48 ◽

Cited By ~ 50

Author(s):

Julie Arenberg Bierer ◽

John C. Middlebrooks

Keyword(s):

Cochlear Implant ◽

Cortical Responses ◽

Channel Interactions

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Long-Term Measures of Electrode Impedance and Auditory Thresholds for the Ineraid Cochlear Implant

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3505.1126 ◽

1992 ◽

Vol 35 (5) ◽

pp. 1126-1130 ◽

Cited By ~ 37

Author(s):

Michael F. Dorman ◽

Luke M. Smith ◽

Korine Dankowski ◽

Geary McCandless ◽

James L. Parkin

Keyword(s):

Cochlear Implant ◽

Neural Tissue ◽

First Year ◽

Electrode Impedance ◽

Cochlear Prosthesis ◽

Detection Thresholds ◽

Auditory Thresholds ◽

Electrical Stimuli

Measures of electrode impedance and of detection thresholds for electrical stimuli were extracted from the records of patients implanted with the Ineraid cochlear prosthesis. An analysis of impedance measures, obtained at 1, 12, 24, and 36 months after surgery, demonstrated (a) a significant decrease in impedance over the first year for electrodes that carried current and (b) significant increases in impedance at 24 and 36 months for electrodes that did not carry current. An analysis of detection thresholds, obtained at the same times as the impedance measures, demonstrated that averaged thresholds for the current-carrying electrodes varied no more than 0.5 dB over the 3-year period. These results support the conclusion that stimulation with the Ineraid device does not produce deleterious changes in the electrodes or in the target neural tissue.

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