Mapping Corticoreticulospinal Motor Control in Chronic Hemiparetic Stroke

NCT ID: NCT06598150

Last Updated: 2025-10-01

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 32 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-05-20
• Study Completion Date: 2026-08-31

Brief Summary

This study uses functional magnetic resonance imaging to map neural activity throughout the central nervous system during a shoulder abduction task to characterize what motor pathways are being used post-stroke.

Detailed Description

Nearly 85% of stroke survivors experience significant unilateral impairment in upper extremity motor control, typically caused by damage to the corticospinal (CST) and corticoreticular (CRT) tracts (i.e., the corticofugal tracts). Alternative neural pathways, such as the contralesional cortico-reticulospinal tract (CRST), can be recruited to achieve movement of the affected arm and hand, but may have undesirable consequences. For example, the diffuse, bilateral branching of reticulospinal neurons can produce abnormal muscle co-activations (synergies) in the paretic limb, and involuntary mirror movements (associated reactions) between limbs. Together, these effects create stereotypical movement patterns post-stroke, and there is growing interest in novel "anti-synergy" interventions to enhance usage of residual CST systems rather than strengthening the CRST. Imaging has the potential to become an invaluable tool for evaluating whether rehabilitative strategies can preferentially access CST versus CRST pathways. However, current functional imaging research has focused on cortical activity, and must theoretically infer what pathway is used. Structural MRI directly assesses changes in white matter pathways, but it is limited to detecting long-term plasticity. To guide new interventions, there is a critical need to directly evaluate what descending motor pathways are active during movement. Thus, the overall objective of this study is to generate a novel fMRI dataset in participants with post-stroke hemiparesis, capturing neural activity during an innovative isometric shoulder abduction task, evaluating differences when abducting the paretic versus non-paretic arm. The investigators will acquire multi-echo fMRI data in individuals with post-stroke hemiparesis and age-matched controls, hypothesizing that increased reliance on the CRST will cause distinct activation patterns during shoulder abduction with the paretic limb, and that this will correlate with individual upper-extremity impairment (Upper-Extremity Fugl-Meyer Assessment). This work is significant because it will provide direct evidence of descending contralesional motor pathway involvement in post-stroke hemiparesis, and demonstrate the utility of neuroimaging for optimizing movements to preferentially engage specific systems and promote desired neural plasticity following injury.

Conditions

Stroke; Hemiparesis

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Shoulder Abduction

Group Type: EXPERIMENTAL

Shoulder Abduction

Intervention Type: OTHER

Individuals will be visually cued to perform short, unilateral, isometric shoulder abduction tasks. A visual display will provide real-time feedback of the shoulder abduction torque, to help the participant target a predetermined torque level.

Interventions

Shoulder Abduction

Individuals will be visually cued to perform short, unilateral, isometric shoulder abduction tasks. A visual display will provide real-time feedback of the shoulder abduction torque, to help the participant target a predetermined torque level.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Adults aged at least 18y
• Able to perform shoulder abduction task (confirmed during screening and initial examination)
• Safe to undergo MRI
• Able to follow visual instructions using MRI-compatible vision correction goggles
• No brainstem or cerebellar lesions
• No severe concurrent medical problems
• Cognitive/attentional capacity to focus on a task
• Able to communicate in English or Spanish

• Have sustained only one unilateral subcortical, ischemic lesion in the territory supplied by the Middle Cerebral Artery (confirmed by clinical or radiological reports) at least one year prior to participation in this project
• Paresis confined to one side, with moderate-to-severe motor impairment of the upper limb (Upper Extremity Fugl-Meyer score between 10 and 45).

Exclusion Criteria

• MRI contraindications
• Severe claustrophobia
• Pregnant women
• Prisoners
• Vulnerable populations
• Diagnosis/history of:
• multiple sclerosis
• brain tumor
• brain radiation
• traumatic brain injury
• dementia
• Parkinson's disease
• Concurrent enrollment in an intervention study
• Concurrent use of medications known to suppress central nervous system activity

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

NIH

Sponsor Role: collaborator

Northwestern University

OTHER

Sponsor Role: lead

Responsible Party

Molly Bright

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Molly G Bright, DPhil

Role: PRINCIPAL_INVESTIGATOR

Northwestern University

Locations

Northwestern University

Chicago, Illinois, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Michelle Medina, BS

Role: CONTACT

anvil@northwestern.edu

872-272-7687

Facility Contacts

Michelle Medina, BS

Role: primary

anvil@northwestern.edu

872-272-7687

Provided Documents

Document Type: Informed Consent Form

View Document

Other Identifiers

1R03HD113915-01

Identifier Type: NIH

Identifier Source: secondary_id

View Link

STU00214855

Identifier Type: -

Identifier Source: org_study_id