Predicting Ipsilesional Motor Deficits in Stroke With Dynamic Dominance Model

We previously characterized hemisphere-specific motor control deficits in the non-paretic arm
of unilaterally lesioned stroke survivors. Our preliminary data indicate these deficits are
substantial and functionally limiting in patients with severe paresis. We have specifically
designed an intervention to remediate the hemisphere-specific deficits in the non-paretic
arm, using a virtual-reality platform, and then follow this training with manipulation
training of a variety of real objects, designed to facilitate generalization and transfer to
functional behaviors encountered in the natural environment. We propose a 2-site, two-group
randomized intervention with a treatment group, which will receive unilateral training of the
non-paretic arm, through our Virtual Reality and Manipulation Training (VRMT) protocol. This
intervention protocol is grounded in the premise that targeted remediation of fundamental
control deficits exhibited by the non-paretic arm will generalize and transfer beyond
practiced tasks to performance of activities of daily living (ADL). This approach contrasts
with the more pragmatic approach of task-specific training of essential ADL's, which is
limited in scope, more cumbersome, and ignores known fundamental motor control deficits. Our
control group will receive conventional intervention, guided by recently released practice
guidelines for upper limb intervention in adult stroke. The impact of the proposed research
is that we address persistent functional performance deficits in chronic stroke patients with
severe paresis, who's non-paretic arm impairments are generally ignored in most current
rehabilitation protocols. Our first aim addresses the overall effectiveness of this
intervention, relative to our control group: To determine whether non-paretic arm VRMT in
chronic stroke survivors with severe paresis will produce durable improvements in non-paretic
arm motor performance that will generalize to improve functional activities and functional
independence to a greater extent than conventional therapy focused on the paretic arm. Our
second aim focuses on the mechanistic basis of potential training-related improvements in
motor performance: To determine whether intervention-induced improvements in non-paretic arm
performance are associated with improvements in hemisphere-specific reaching kinematics.
Finally, our third aim monitors for potential negative effects of our experimental
intervention on paretic arm impairment.

Inclusion Criteria:

- neuroradiological confirmation of unilateral brain damage with residual
upper-extremity weakness

- deficits in ipsilesional arm performance

Exclusion Criteria:

a history of:

1. neurological disease other than stroke (e.g., head trauma)

2. a major psychiatric diagnosis (e.g., schizophrenia, major affective disorder),

3. hospital admission for substance abuse

4. peripheral disorders affecting sensation or movement of the upper extremities,
including pain or arthritis

5. currently taking prescription drugs with known sedative properties that are
interfering with sensory-motor function

6. significant joint pain that is activity limiting