A Closed Loop Neural Activity Triggered Stroke Rehabilitation Device

The aim of this study is to determine if functional muscle stimulation, in addition to non-invasive neurostimulation through the tongue (TDU), directed by electroencephalogram (EEG) output, can increase the extent of stroke recovery on behavioral measures and induce brain plasticity as measured by functional magnetic resonance imaging (fMRI).

Adult stroke patients with upper extremity motor impairments (henceforth "experimental group"), healthy controls, and participants with risk factors for stroke, without upper extremity impairment (allowing them to serve as controls for patients with upper extremity impairments (henceforth "control group")), will be recruited in this study. Half of the participants in the experimental group will be randomly assigned to the EEG-BCI (brain-computer interface) training ("closed-loop") group and will receive training on the BCI task along with muscle and tongue stimulation. The other half of the participants in the experimental group receiving traditional rehab will not receive any kind of FES or tongue stimulation for the first 8-10 weeks of study period and then will start receiving BCI-FES-tongue stimulation rehab therapy.

All participants without UE impairment in Control group 1 will receive 4-6 (minimum 4, up to a maximum of 6) sessions of training on the BCI system and pre- and post MRI and 2 behavioral testing sessions.

Addition of a Control group 2 is consistent with the AHA grants - Twenty four ischemic stroke patients with moderate upper extremity (dominant right hand affected) impairment (score of 1 or 2 on the motor sub-component of the NIH stroke scale (NIHSS) and ARAT score 20-45); no upper extremity injury or conditions that limited use prior to the stroke; and pre-stroke independence with a Modified Rankin Score of 0 or 1), will be recruited in this arm. All participants in this group will receive MR sessions and behavioral testing similar to the Experimental group.

Addition of an Experimental group receiving EEG-BCI-bilateral FES intervention using the recoveriX system: recoveriX is a brain driven rehabilitation system for stroke patients that pairs mental activities with motor functions. Through the EEG-based recoveriX BCI system, the brain receives visual and tactile feedback in real-time, making rehabilitation more effective. A stroke patient imagines a hand movement while receiving visual feedback through a virtual avatar, and tactile feedback through electrical muscle stimulation paired to the patient's imagined movement, with the aim that these patients might regain the volitional ability to grasp following therapy. Unlike the current EEG-BCI-FES intervention that involves stimulation of only the impaired arm, with recoveriX, both arms are simultaneously stimulated during the course of the intervention.

Specific Aims

To determine if functional muscle stimulation of the arms, in addition to non-invasive neurostimulation through the tongue (TDU), directed by electroencephalogram (EEG) output, can increase the extent of stroke recovery as measured by behavioral measures and induce brain plasticity as measured by functional magnetic resonance imaging (fMRI).

Primary objective

• To examine the effect of EEG guided functional muscle stimulation on improvement in upper extremity function

Secondary objective

• To examine plasticity changes as measured by EEG/fMRI measures before and after EEG guided functional muscle stimulation.

Inclusion criteria

(Experimental Group):

• Stroke patients with persistent upper extremity (UE) deficits

Inclusion criteria

(Control Group 1)

• Stroke patients without UE impairments
• Participants with risk factors for stroke
• healthy controls

• No known neurologic, psychiatric or developmental disability

Inclusion criteria

(Control Group 2)

• Stroke patients with persistent upper extremity (UE) deficits
• Moderate upper extremity (dominant right hand affected) impairment (score of 1 or 2 on the motor sub-component of the NIH stroke scale (NIHSS) and ARAT score 20-45)
• No upper extremity injury or conditions that limited use prior to the stroke
• Pre-stroke independence with a Modified Rankin Score of 0 or 1, for the standard FES only intervention.

Exclusion criteria

(for all participants):

• Allergic to electrode gel, surgical tape and metals
• Participants under treatment for infectious diseases or having apparent oral lesions or inflammation will be excluded from the study
• Women who are pregnant or may become pregnant during the course of the study will be excluded
• Participants with contraindications for MRI will be offered the opportunity to participate in the interventions study only (e.g. EEG-BCI-FES and behavioral testing)

Exclusion criteria

(for healthy controls)

• Contraindications for MRI
• Allergic to electrode gel, surgical tape, and metals.