Remediation of the Non-Paretic Arm in Stroke

The investigators previously elaborated hemisphere specific motor deficits in the non-paretic
arm of chronic stroke survivors with unilateral hemisphere damage. The investigators showed
that these deficits are associated with substantial limitations in performance of activities
of daily living (ADL), an effect exacerbated by contralesional paresis due to forced reliance
on the non-paretic arm. The investigators now hypothesize that the combination low moderate
to severe paresis (Fugl-Meyer Score < 35) and persistent motor deficits in the non-paretic
arm limits functional independence in chronic stroke survivors. The investigators predict
that intense remediation focused on improving the speed, coordination, and accuracy of the
non-paretic arm should improve functional independence, as well as improving paretic arm
function due to increased participation in daily activities. Unfortunately, the usual
standard of care in rehabilitation for survivors with low-moderate to severe paresis tends to
focus on task training in essential ADL activities, rather than on intensive remediation.
Previous research has shown that non-paretic arm deficits depend on the hemisphere that is
damaged by stroke, such that left hemisphere damage (LHD) impairs trajectory features,
including speed and smoothness, while right hemisphere damage (RHD) impairs the ability to
bring the arm to rest at an accurate and stable position. The investigators have designed a
training program to address both of these motor components and to improve the speed and
dexterity of the non-paretic arm. The investigators propose a randomized study design with
two tracts, two periods and four assessments. Participants will first complete 2 baseline
assessments, spaced 3 weeks apart. Following completion of the second assessment,
participants will be randomly assigned to one of two tracks: Track 1 will receive three weeks
of arm training, followed by 3 weeks of a comparison condition. Participants assigned to
track 2 will receive three weeks of the comparison condition, followed by 3 weeks of arm
training. Then, all participants will complete an end-of-period assessment, and a follow-up
assessment for retention, 3 weeks after completion of the two periods. Pilot results indicate
that non-paretic arm training produces substantial improvements in motor performance and
functional independence as well as reducing paretic arm impairment. This is an essential
first-step in developing a rehabilitation protocol focused on remediating both arms of
severely impaired stroke survivors.

Inclusion Criteria:

1. Subjects will be between 21 and 85 years old of either gender

2. Subjects will demonstrate cognitive abilities required to follow commands and engage
in the experimental task

3. Subjects will have had a unilateral stroke at least 3 months prior to participation
resulting in upper extremity motor deficits

Exclusion Criteria:

1. hospitalization for substance abuse and/or a major psychiatric diagnosis
(schizophrenia);

2. non-stroke neurological diseases that may affect ability to perform task or upper limb
motor function

3. certain peripheral movement restrictions, such as neuropathy

4. neuroradiological confirmation of concomitant damage to the cerebellum or brain stem
or extensive periventricular white matter changes (based on consultation with
neuroradiology)