Stroke Research

Study Overview

RESTORE is a prospective randomized controlled trial looking at the impact of early intensive robotic rehabilitation on stroke recovery. Participants are randomized into different groups that will receive extra therapy time using the Kinarm robotic exoskeleton. Using the Kinarm, participants will go through a series of tasks to exercise the upper extremity as part of their rehabilitation program.   

Using the Kinarm allows participants to do many more repetitions to exercise the arms in a shorter amount of time then would be typically possible in a standard therapy session with a therapist. The Kinarm will be able to make several hundred repetitions with the participant, and allow them to potentially push themselves harder; working as close to their own maximum ability as they can in a safe and controlled setting. The Kinarm can also measure and track any improvements that the stroke survivors make, down to the millisecond and millimeter, so that our participants can see small changes from day to day that may not be noticeable to them in daily activity. 

Team Members Involved

Trainees:

• Emilee Cowan-Nelson

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Collaborators:

• Dr. Mark Bayley (Co-Investigator, Toronto ON)
• Dr. Stephen Scott (Co-Investigator, Kingston ON) 

Study Overview

Many stroke survivors have aphasia, an impairment of language affecting the production or understanding of speech and the ability to read and write.

Non-fluent aphasia often results from stroke-related damage to Broca’s area. Recent research has focused on using brain stimulation to augment recovery of non-fluent aphasia. Several small studies have suggested 1 Hz repetitive Transcranial Magnetic Stimulation (rTMS) over the contralesional right pars triangularis (the right sided homologue of Broca’s area), when coupled with speech language therapy, can improve speech production in individuals with non-fluent aphasia poststroke. rTMS appears to inhibit inappropriate recruitment of the right pars triangularis in language production and promote reorganization of the left hemisphere when coupled with speech language therapy (SLT) leading to improvements in language function.

More intense SLT may encourage greater neuroplasticity and promote better recovery of language. Pairing rTMS with more intensive SLT treatments could potentially lead to better outcomes in stroke survivors with longstanding aphasia. One such intensive, novel SLT treatment is a technique known as Multi-Modality Aphasia Therapy (M-MAT). M-MAT improves spoken language production through shaping of responses and social-mediated repetitive practice. Participants work with a speech-language pathologist (SLP) in small groups for 2-4 hours/day for 2 weeks or more. We suspect pairing rTMS with M-MAT will result in significantly enhanced recovery of aphasia.

Further, language recovery post-stroke is traditionally thought to occur mainly in the first 2-3 months. Recent studies, however, on early SLT versus later therapy have shown mixed results. We are not aware of any rTMS trials that directly examine the impact of varying timing post stroke. Thus, we plan to compare sub-acute stroke (<3 months post-stroke) and chronic stroke (>6 months post-stroke) to better understand how timing affects response to our intervention.

Team Members Involved

Trainees:

• Trevor Low

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Study Overview

Robotic therapy allows for more intense, tightly controlled rehabilitation to be performed compared to what is currently offered in clinical settings. This is due to the volume of repetitions that can be performed, something which has been shown to benefit people’s rehabilitation following stroke. Robots also allow for the explicit rehabilitation of the knowledge people have of their limbs in the absence of vision – a sense called proprioception.

Transcranial Direct Current Stimulation (tDCS) is a safe method of brain stimulation whereby two sponge electrodes are placed on the scalp. A small current (up to 2mA) is passed between the electrodes, modulating the excitability of the brain tissue through which the current passes. Early evidence shows that when paired with a training intervention, this small change in excitability is thought to enhance learning of motor and sensory skills in both healthy and stroke populations. To date, tDCS has not been investigated in relation to proprioception in a chronic stroke population, nor has it been investigated alongside a robotic rehabilitation intervention for sensory purposes.

This study will investigate a combination of two exciting therapies after stroke. One goal is to determine whether robotic treatment can improve proprioception after stroke. Another goal of the study is to examine whether applying tDCS, alongside robotic therapy, can enhance the improvements made in proprioception after stroke.

Team Members Involved

Trainees:

• Matthew Chilvers

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Study Overview

Following a stroke, rehabilitation is critical for reducing stroke-related disabilities. While the current standard of care has shown some success in rehabilitating the upper limb, it can be difficult for many centre's to meet the time and intensity requirements based on staffing and funding. Transcranial magnetic stimulation (TMS) is a safe, non-invasive method of stimulating the human brain with changing magnetic fields. Repetitive TMS (rTMS) may have the potential to enhance the brain’s ability to re-learn specific functions and reduce the amount of standard therapy required to achieve certain functional gains after stroke.

Currently, there are insufficient large-scale clinical trials demonstrating the efficacy of rTMS for post-stroke functional motor recovery due to the lack of a lack of consensus regarding the optimal protocol for the clinical application of TMS in stroke populations. The Canadian Platform for Trials in Non-Invasive Brain Stimulation (CanStim) is a national platform that aims to facilitate multi-center clinical trials for non-invasive brain stimulation interventions to augment recovery from stroke. CanStim investigators convened a multidisciplinary team of experts in rTMS from institutions across Canada to form the CanStim Consensus Working Group and develop consensus recommendations for a protocol to deliver rTMS as an adjunct to standard physiotherapy in a national stroke rehabilitation clinical trial.

Team Members Involved

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Collaborators:

• Dr. Alexander Thiel (Principal Investigator, Montreal QC)
• Dr. Jodi Edwards (Principal Investigator, Ottawa ON)
• Dr. Lara Boyd (Co-Investigator, Vancouver BC)
• Dr. Catherine Mercier (Co-Investigator, Quebec QC)
• Dr. Marc Roig (Co-Investigator, Montreal QC)

Study Overview

Animal studies have found that thousands of upper limb reach to grasp repetitions may be necessary for driving functional recovery following a stroke; however, current doses of upper limb movement practice during rehabilitation are far below that of animal studies. This is understandable as therapists have to address multiple body functions affected by the stroke during their therapy sessions. One potential method for increasing movement practice is to facilitate greater incorporation of the upper limb into daily activities. Unfortunately, this potential solution is not straightforward due to the increased reliance on the less affected upper limb following a stroke. Information from wearable sensors may help counteract this over-reliance by facilitating increased awareness of what the affected upper limb is doing, and by providing external cues to use the affected upper limb. Current wearable devices that rely on accelerometer technology do not provide information that is easy to interpret; however, a new wrist-worn device (the TENZR) has been developed that is able to provide repetitions of reach to grasp movements (called hand counts). Preliminary studies have shown that the technology used in this wearable device has suitable reliability and validity in people with stroke. Cuing from wearable sensors alone may not be enough to facilitate greater practice as use of the affected limb can be very frustrating when there is reduced functional capacity. The next step is to determine whether wearing this device in conjunction with a program aiming to increase functional capacity (i.e. exercise) is feasible and can increase the amount of movement practice for the duration of the time the device is worn.

The purpose of this study is to determine the feasibility of a treatment program that involves feedback from the TENZR wearable device in combination with an exercise program, and to determine the effect that the treatment program has on the amount of stroke-affected upper limb use.

Team Members Involved

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Collaborators:

• Dr. Janice Eng (Principal Investigator, Vancouver BC)
• Dr. Ruth Barclay (Co-Investigator, Winnipeg MB)
• Dr. Mark Bayley (Co-Investigator, Toronto ON)
• Dr. Sandra Black (Co-Investigator, Toronto ON)
• Dr. Bradley MacIntosh (Co-Investigator, Toronto ON)
• Dr. Marilyn Mackay-Lyons (Co-Investigator, Halifax NS)
• Dr. Sepideh Pooyania (Co-Investigator, Winnipeg MB)
• Dr. Michelle Ploughman (Co-Investigator, St. John's NFLD)
• Dr. Robert Teasell (Co-Investigator, London ON)

Study Overview

Stroke is the most common cause of adult disability; more specifically, movement impairments are the most common form of disability caused by stroke. Post-stroke physical rehabilitation is widely regarded as the necessary treatment to allow a stroke survivor to return home after a moderate or moderately severe stroke, and prescription of outpatient rehabilitation for stroke survivors who present with functional movement deficits upon discharge is the current standard of care. Moreover, studies have shown rehabilitation can continue to improve the functional movement abilities of stroke survivors throughout the chronic phases of stroke recovery, even years after the stroke.

Rehabilitation leads to changes in cortical connectivity in the brain, so-called neuroplasticity. These changes include increasing the number of connections between neurons through synaptogenesis, dendritic branching, altered neurotransmitter levels, and remapping of regions within the brain. While neuroplastic changes occur post-stroke independent of rehabilitation, studies show that rehabilitation drives beneficial post-stroke neuroplasticity within the sensorimotor system, positively contributing to enhanced improvements in functional status. However, studies in animal models have demonstrated that a large volume of repetitions are required to drive this beneficial neuroplasticity.

The Axem Home prototype is a rehabilitation system designed to be used independently by a stroke survivor to facilitate physical rehabilitation exercises in their home environment. This system involves displaying the users' (non-diagnostic) brain activity during upper-extremity rehabilitation exercises as well as their adherence to rehabilitation goals. There is preliminary evidence that the provision of brain activity feedback from the motor cortex to patients during rehabilitation could provide an additional enhancement to the effectiveness of their rehabilitation exercises. The purpose of this study is to determine the safety and feasibility of using the Axem Home prototype to facilitate independent, at-home post-stroke physical rehabilitation.

Team Members Involved

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Collaborators:

• Axem Neurotechnology 

Study Overview

Cerebral Palsy is the general term given to a group of neurological disorders that develop close to, or at the time of birth, or appear very early in infancy. Pediatric stroke is one cause of Cerebral Palsy. Similar to the adult stroke study RESTART, we are interested in determining how neurologic function has been affected in children with cerebral palsy. 

Currently standardized clinical rehabilitation assessments for children with cerebral palsy focus heavily on measuring motor function. We are interested in better understanding problems with sensory function that occur after pediatric stroke. The Kinarm robotic exoskeleton  is currently being used to help better assess sensorimotor function in children with cerebral palsy in collaboration with Dr. Adam Kirton's lab. Our robotic exoskeleton is advantageous in determining how sensorimotor function is affected in children with cerebral palsy, as assessments are more accurate, and can be done in a non-invasive manner. It is important to accurately assess how motor and sensory function has been affected in children with cerebral palsy, because being able to fully understand how neurological function has been affected and may be useful in planning future treatment.  

Team Members Involved

Research Staff:

• Mark Piitz
• Alexandra McKinnon

Collaborators:

• Dr. Adam Kirton (Co-Investigator, Calgary AB)