Skip to main content
OpenTrials
Completed

NCT Number: NCT02188420

Finding an Optimal Latency for Paired Associative Stimulation in People With Chronic Stroke

After a stroke, there is an exaggerated inhibitory influence from the non-stroke hemisphere to the stroke hemisphere. Brain stimulation using repetitive transcranial magnetic stimulation (rTMS) to the non-stroke hemisphere can decrease this inhibition. Paired Associative Stimulation (PAS) may be a more effective way to produce this same inhibition, as shown in healthy subjects. However, it is not known whether this will translate to people with stroke. PAS consists of a peripheral nerve stimulus paired a short time later with a cortical stimulus to change the excitability within the brain. Thus the investigators will apply PAS to people with stroke, but the investigators need to first determine the most effective interpulse interval (IPI) between the peripheral and cortical stimuli. Our research question is which of three different IPIs is most effective in changing the excitability of the brain.

The purpose of this study is to determine the optimal IPI between a peripheral nerve pulse and a cortical stimulus that will be most effective in changing excitability of the brain in people with chronic stroke. The investigators hypothesize that the cortical excitability of the nonstroke hemisphere will be most inhibited with the latency-5ms condition.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Stroke Brain Diseases Cardiovascular Diseases Central Nervous System Diseases Cerebrovascular Disorders Nervous System Diseases Vascular Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of Minnesota Clinical and Translational Science Institute

Minneapolis, Minnesota, 55414, United States

About this study

Numerous PAS studies have been done in healthy subjects and all have been done safely. The proper interpulse interval in healthy individuals between the peripheral nerve stimulus and the cortical stimulus is known to be "latency-5ms." However, this may be different in individuals with stroke.

Specific Aim: what is the optimal interpulse interval to achieve the maximum inhibitory effect in the nonstroke hemisphere?

We will recruit three subjects with chronic stroke. Electroencephalography (EEG) will be used to determine the latency between the peripheral nerve stimulus and the sensory evoked potential in each subject. We will then assess the following IPIs on each subject in a random order: "latency" - 3ms, -5ms and -7ms. There will be a fourth condition of "latency" + 100ms (known to have no effect) to be used as a control. The washout period will be at least one week between each of these conditions.

The optimal IPI will be determined from these tests by comparing single pulse transcranial magnetic stimulation (TMS) measures for cortical excitability. Prior to each treatment, each subject will receive 20 single pulse cortical stimuli to serve as pretest data. The post tests for each condition will consist of 20 single pulse cortical stimuli at 0, 5, 10, 15, 30, 45 and 60 minutes after the PAS condition. Data analysis will consist of a single-subject analysis with the two standard deviation bandwidth method of each post-test compared to pre-test.

We hypothesize that there will be no adverse advents and that this optimal IPI will be "latency"-5ms.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • stroke (ischemic or hemorrhagic) of greater than 6 months duration
  • impairment in the paretic hand
  • over 18 years old
  • male or female
  • on mini mental status exam must have score of 22 or higher
  • must have elicitable motor evoked potential (MEP)

Exclusion criteria

  • seizure within the past two years
  • receptive aphasia
  • epileptogenic medication
  • major psychiatric disorder
  • other interfering comorbidities
  • pregnancy

Treatment and study plan

Transcranial Magnetic Stimulation will be applied to the primary motor cortex at the interstimulus interval of ("Latency" - 3ms)

Device

Transcranial Magnetic Stimulation will be applied to the primary motor cortex at the interstimulus interval of ("Latency" - 3ms) where "latency" refers to the amount of time for the arrival of a sensory evoked potential as determined by EEG.

Other names: TMS, Magstim

Transcranial Magnetic Stimulation will be applied to the primary motor cortex at the interstimulus interval of ("Latency" - 5ms)

Device

Transcranial Magnetic Stimulation 5ms

Other names: TMS

ranscranial Magnetic Stimulation will be applied to the primary motor cortex at the interstimulus interval of ("Latency" - 7ms)

Device

Transcranial Magnetic Stimulation 7ms

Other names: TMS

Transcranial Magnetic Stimulation Time 100ms

Device

Active Compator

Other names: TMS

Primary outcomes

  1. Change in Cortical Excitability Using Single TMS Pulses

    Time frame: Change from pretest (immediately prior to PAS application) to posttest which will occur over the 60 minutes that follow PAS application.

    Assess average size of 20 motor evoked potentials via electromyography (EMG) signal resulting from single TMS pulses to the motor cortex. Measurements taken before and after paired associative stimulation treatment at each session.

Sponsors and collaborators

Lead sponsor

University of Minnesota

Other

Registry information

Official study title

Effect of Different Interpulse Intervals of Paired Associative Stimulation on Cortical Excitability in People With Chronic Stroke

Important dates

Study start
2014
Primary completion
2015
Study completion
2016
First posted
Jul 11, 2014
Registry last updated
Feb 6, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.