Investigation on the Cortical Communication System
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-70
SponsorUMC Utrecht
About this trial
The goal of this clinical trial is to demonstrate communication through a brain implant in people in locked-in state, i.e. people with severe paralysis and communication problems.
The main questions it aims to answer are efficient and stable control of Brain-Computer interface (BCI) functions for communication with attempted hand movements and operation of a keyword-based speech BCI.
Participants will be implanted with four electrode grids, with in total 128 electrodes, on the surface of the brain and a connector on the skull. Participation includes visits of researchers for recording and training at home, 2-3 times per week for one year. Extension of participation after one year is possible.
If successful, the participant will be able to use the BCI at home independently, without the presence of a researcher.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
18-70 years
Clinical diagnosis of locked-in state state or likelihood of soon progressing into LIS (within an estimated 2 years), caused by traumatic brain injury, brainstem stroke, neurodegenerative disease, neuromuscular disease or another cause
• Current or imminent complete or incomplete tetraplegia (quadriplegia) or tetraparesis (quadriparesis)
• Current or imminent motor-related speech impairment (dysarthria or anarthria)
Disqualifiers
Performance on formal neuropsychological testing that indicates a significant current or recent psychiatric disorder, cognitive or behavioral impairment, that would interfere with obtaining informed consent or fully participating in study activities
Medical conditions contraindicating surgery of a chronically implanted device or that could interfere with study participation (for example active infections, unexplained fever, existing scalp lesions or skin breakdown, osteomyelitis, hepatitis, any autoimmune disease/disorder, epilepsy, skin disorders causing excessive skin sloughing or poor wound healing, cranioplasty, significant cardiovascular, metabolic, or renal impairments, chronic oral or intravenous use of steroids or immunosuppressive therapy, active cancer within the past year or requires chemotherapy, uncontrolled autonomic dysreflexia within the past 3 months, hydrocephalus with or without an implanted ventricular shunt or a medical contraindication to stop anti-coagulant medications during surgery)
Presence of pre-surgical findings in anatomical, functional, and/or vascular neuroimaging that makes achieving implant locations too challenging or incompatible with desired risk levels
Inability to undergo MRI for pre-implantation evaluation, for example due to the presence of implanted devices that are incompatible with MRI, which may include pacemakers, cardiac defibrillators, spinal cord or vagal nerve stimulators, deep brain stimulators, and cochlear implants
Trial design
Design model
Single group
Treatments tested in this trial
ECoG (electrocorticography) sensing
DeviceImplant electrodes and pedestal connector and use, through amplifier and decoding, for control of BCI
Treatment groups
2 Participants
are divided into 1 treatment groupGroup A: ECoG (electrocorticography) sensingExperimental treatment 1 intervention
Trial outcomes
Primary outcomes
1
Usability of the BCI system - Accuracy
Accuracy: \>80% sensitivity (true positive rate) for 1-command control, and 90% sensitivity and 80% classification accuracy (distinguishing between the six classes) for 6-command control
Time frame
1 year2
Usability of the BCI system - speed
Speed characters or keywords per minute
Time frame
1 year3
Usability of the BCI system - subjective workload Visual Analogue Scale (VAS)
Subjective Workload: Visual Analogue Scale Continuous scale: Little to no effort (0) - Much effort (5). Lower numbers are better.
Time frame
1 year4
Usability of the BCI system - subjective workload National Aeronautics and Space Administration-Task Load Index (NASA-TLX)
Subjective Workload: National Aeronautics and Space Administration-Task Load Index Scale: 21 point Likert-type scale. Lower numbers are better.
Time frame
1 yearSecondary outcomes
1
Stability of BCI performance (electrode-tissue interaction)
Longitudinal data of the 24-hour cycle after implantation of the impedance (in Ω). The data are fitted to determine trends and variance, over weeks, to determine improvement or deterioration of electrode-tissue interaction.
Time frame
2 years2
Stability of BCI performance (signal)
Longitudinal data of the 24-hour cycle after implantation of the raw power (after wavelet transform, in arbitrary units). The data are fitted to determine trends and variance, both within 24 hrs to detect a possible circadian pattern and over weeks, to determine improvement or deterioration of signal amplitude.
Time frame
2 years3
Stability of BCI performance (modulation)
Longitudinal data of the 24-hour cycle after implantation of the task-related modulation in power (correlation in r2). The data are fitted to determine trends and variance, over weeks, to determine improvement or deterioration of modulation.
Time frame
2 years4
Stability of BCI performance (performance)
Longitudinal data of the 24-hour cycle after implantation of the BCI performance (task accuracy). The data are fitted to determine trends and variance, both within 24 hrs to detect a possible circadian pattern and over weeks, to see improvement or deterioration of accuracy.
Time frame
2 yearsOther outcomes
1
Assess device specifications for future application of HD ECoG-BCIs
qualitative description on device specifications and experimental parameters, such as the specific decoder settings, for future, larger scale, application of HD ECoG-BCIs.
Time frame
2 yearsSponsors and contacts
Click on the lead sponsor to view all of their trials.
UMC Utrecht
Lead sponsor
Johns Hopkins University
Collaborator
Source ClinicalTrials.gov