Effect of EEG-EMG based hybrid brain-computer interface operated hand exoskeleton for poststroke hand functional recovery

ISRCTN ISRCTN13139098
DOI https://doi.org/10.1186/ISRCTN13139098
Protocol serial number REC/16/0089
Sponsor UKIERI
Funders UK-India Education and Research Initiative, Department of Science and Technology, Ministry of Science and Technology
Submission date
15/05/2018
Registration date
22/06/2018
Last edited
20/11/2020
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Circulatory System
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
This Physical Practice (PP) and Mental Practice (PP) based neurorehabilitation protocol was inspired by the researchers’ earlier works on BCI based hand rehabilitation producing effective motor recovery. In their first clinical trial the PP part was manual and the MP part was based on a BCI based computer game-play, although there was no exoskeleton assistance in either stage. The study established the feasibility of the PP+MP strategy, improving motor recovery, but there was no significant improvement in the BCI performance. In the second clinical trial the hand exoskeleton was introduced in both the PP and MP stage. The exoskeleton was driven in assist-as-needed mode although the difficulty level of PP was set to a fixed level. In the MP stage the exoskeleton provided proprioceptive neurofeedback. This led to improvement in BCI performance and motor recovery. Recent findings suggest that the performance-based challenge level adjustment during PP has a positive impact on motor recovery. Moreover, the hybrid-BCI (h-BCI) approaches are found to be more reliable as compared to the conventional BCI systems. Therefore, in this study the difficulty level of the PP stage was adjusted according to the performance of the participants and the MP stage was driven by an EEG-EMG correlation based h-BCI system with a hand exoskeleton based proprioceptive neurofeedback.

Who can participate?
Patients aged 18-80, 6 months to 2 years after a stroke

What does the study involve?
All participants undergo the same intervention for 6-8 weeks. The intervention is given 1-3 times per week and consists of two stages. The first stage is the Physical Practice (PP) stage of 30 min followed by a Mental Practice (MP) stage of almost an hour including the BCI calibration time of around 16 min. The PP stage is of 30 min duration during which a hand exoskeleton device provides repetitive finger grasping and extension exercise in assist-as-needed mode. The difficulty level of the PP is adjusted according to the ability of the participant. In the MP stage the participants are given h-BCI based neurofeedback. In one particular session of the MP there are 5 runs of about 7 min 30 sec each consisting of 40 trials, in each of which the participants are asked to perform a left/right hand grasp attempt. The exoskeleton is worn in the impaired hand of the participant, whereas the other hand is placed on a soft ball on top of the table. Among five runs, the first two are for calibrating the BCI system and the rest of the three are for giving online neurofeedback. Hand functional recovery is measured using once a week to investigate the effectiveness of the intervention. Motivation and fatigue are assessed before and after each therapy session to evaluate the usability of the intervention.

What are the possible benefits and risks of participating?
After the end of the clinical trial the participants are expected to gain the motor functionality of their impaired hand motions such as grasping, gripping, pinching or overall hand movements, which could also be reflected in carrying out their daily living activities. The devices used for brain signal acquisition (EEG electrodes) and the physical practice (the hand exoskeleton device) are all non-invasive and the therapy was also designed in consultation with the occupational therapist to keep the therapeutic task within the tolerable limits. Hence, there are no risks associated with the intervention.

Where is the study run from?
Ulster University (UK)

When is the study starting and how long is it expected to run for?
March 2017 to March 2020

Who is funding the study?
1. UK-India Education and Research Initiative
2. Department of Science and Technology, Ministry of Science and Technology (India)

Who is the main contact?
Prof. Girijesh Prasad
g.prasad@ulster.ac.uk

Contact information

Prof Girijesh Prasad
Public

MS 218
School of Computing, Eng & Intel. Sys
Magee Campus
Northland Road
Londonderry
BT48 7JL
United Kingdom

Phone +44 (0)28 7167 5645
Email g.prasad@ulster.ac.uk

Study information

Primary study designInterventional
Study designNon-randomised uncontrolled study
Secondary study designNon randomised study
Study type Participant information sheet
Scientific titleA BCI operated hand exoskeleton based neuro-rehabilitation system for movement restoration in paralysis
Study acronymhBCI-hEXO
Study objectivesThe study hypothesis is that if there is a neurorehabilitation protocol involving physical and mental practice, where the physical practice is mediated by a hand exoskeleton in assist-as-needed mode and the mental practice is mediated by an EEG-EMG band power correlation based BCI operated hand exoskeleton with visual and proprioceptive neurofeedback, then the proposed neurorehabilitation protocol would be a clinically effective and usable solution for hand functional recovery of the chronic stroke patients.
Ethics approval(s)Ulster University Research Ethics Committee, 31/03/2017, ref: REC/16/0089
Health condition(s) or problem(s) studiedChronic stroke patients suffering from post-stroke hand plegia on either side of the body (left/right)
InterventionParticipants underwent hand therapy sessions with a frequency of 1-3 times/week, for a period of 6-8 weeks. Each therapy session consists of a 30 min long Physical Practice (PP) mediated by a hand exoskeleton in assist-as-needed mode. This is followed by a Mental Practice (MP) session of 1 hour long, mediated by a brain-computer interface operated hand exoskeleton with visual and proprioceptive neurofeedback. The resting state MEG was also recorded once a week to investigate the brain-connectivity related changes during the rehabilitation process. The motivation and the fatigue measurements were taken both before and after each session using visual analog scale (VAS) based assessment. Once a week, the motor recovery assessments were taken using Action Research Arm Test (ARAT) and by measuring the grip-strength (GS) of the participants.
Intervention typeDevice
Phase
Drug / device / biological / vaccine name(s)
Primary outcome measure(s)

Hand functional recovery measured using action research arm test (ARAT) and the grip-strength (GS) measurement on a weekly basis for a period of 6-8 weeks

Key secondary outcome measure(s)

Motivation and fatigue measured using the visual analog scale (0-10 cm) before and after each therapy session

Completion date30/03/2020

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
Upper age limit80 Years
SexAll
Target sample size at registration20
Key inclusion criteria1. Male and female post-stroke volunteers, in the age group of 18-80 years and have normal or corrected to normal vision (e.g. normal vision by using glasses)
2. Six months – two years post-stroke since the first episode of stroke: this is to capture stroke survivors within the chronic stage and also to ensure the stage of fast spontaneous recovery has finished
3. Able to follow two-part spoken or written commands: this is to ensure stroke survivors can provide informed consent and also to ensure they will be able to comply with therapy
4. Have movement disability in at least one of their hands due to stroke
5. Able to get in and out of a low seat unassisted
6. Ready to remove all body piercings
Key exclusion criteria1. Aged less than 18 years or above 80 years
2. Known to have a progressive neurological condition, any serious medical or psychological diseases which are likely to seriously affect their ability to continue with experimentation
3. Have metal or active implants in their body (excluding dental fillings or crowns)
4. Known to suffer from claustrophobia
5. Pregnant or breastfeeding
6. Gross cognitive impairment or disorientation, evidenced by a score of <21 in the Mini-Mental State Examination (MMSE); the MMSE is an 11-item reliable and valid measure of cognitive function (Folstein, Folstein & McHugh 1975), such that they are unable to follow verbal or written instruction
Date of first enrolment12/04/2017
Date of final enrolment24/04/2017

Locations

Countries of recruitment

  • United Kingdom
  • Northern Ireland

Study participating centre

Ulster University
Intelligent Systems Research Centre
School of Computing and Intelligent Systems
Faculty of Computing and Engineering
Magee campus
Northland Road
Derry~Londonderry
BT48 7JL
United Kingdom

Results and Publications

Individual participant data (IPD) Intention to shareNo
IPD sharing plan summary
IPD sharing planData will be available indefinitely at Dryad Digital Repository and in the University Data Repository of the Ulster University. All of the individual participant data collected during the trial will be shared after deidentification. Participant Information sheet, Study Protocol, Filter Form, Statistical Analysis Plan, Informed Consent Form, and Clinical Study Report will also be available. Data will be available immediately following publication with no end date for anyone who wishes to access the data for any purpose.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 01/10/2018 Yes No
Results article results 01/11/2018 20/11/2020 Yes No
Results article results 01/01/2019 20/11/2020 Yes No
Results article results 01/05/2019 20/11/2020 Yes No
Results article results 01/01/2020 20/11/2020 Yes No
Results article results 26/10/2018 20/11/2020 Yes No
Results article results 01/12/2018 20/11/2020 Yes No
Participant information sheet Participant information sheet 11/11/2025 11/11/2025 No Yes

Editorial Notes

20/11/2020: Publication references added.
14/12/2018: Publication reference added.