Manual Dexterity Modifications After Application of tSMS Over the Primary Motor Cortex (M1)

Not Applicable

• Conditions: Neurologic Disorder; Manual Dexterity; Stroke
• Interventions: Device: tSMS; Device: Sham tSMS

• Registration Number: NCT05260190
• Lead Sponsor: Universidad Rey Juan Carlos

Brief Summary

Transcranial static magnetic field stimulation (tSMS) is a novel brain stimulation technique that has been shown to be safe and effective in modifying biological parameters when applied to the cerebral cortex. Its application decreases cortical excitability, regardless of the polarity of the magnetic field, reducing the amplitude of motor evoked potentials (MEP). tSMS is presented as a potentially useful tool in the management of the interhemispheric inhibition, a condition present in neurological pathologies such as stroke or multiple sclerosis. Despite having demonstrated neurophysiological effects in previous studies, the effects of tSMS application on force production and manual dexterity, have not yet been clearly established.

The present study aims to evaluate changes in force production, manual dexterity, and fatigue after unilateral application of a tSMS session on the primary motor cortex (M1). It is hypothesized that the application of tSMS will momentarily decrease the parameters of strength and manual dexterity in the upper limb contralateral to the stimulated cortex, without changes in the strength and dexterity of the unstimulated hemibody. These parameters may show an increase in the unstimulated hemibody. If the hypothesis is confirmed, it could be considered a valid treatment for health conditions presenting interhemispheric inhibition.

Detailed Description

Not available

Study Timeline

• Study Start: 2021-09-01
• Status Verified: 2022-02
• Study First Submitted: 2022-02-10
• Study First Submitted QC: 2022-02-23
• Last Update Submitted: 2022-02-23
• Study First Posted: 2022-03-02
• Last Update Posted: 2022-03-02
• Primary Completion: 2022-11-01
• Study Completion: 2023-04-01

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 44

Inclusion Criteria

• Age between 18 and 60 years.
• Absence of cognitive impairment.
• Adequate understanding of verbal and written information, sufficient to complete the tests.

Exclusion Criteria

• Presence of metallic implants (e.g., neurostimulator, pacemaker, cochlear implant, or metallic elements in the head or around the eyes).
• Diagnosis of epilepsy or being under treatment with antiepileptic drugs.
• Diagnosis of unstable cardiovascular disease.
• Diagnosis of any disease or condition that may interfere with this study.
• Use of drugs that may influence with neuromuscular function (muscle relaxants or some analgesics...).

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
tSMS	tSMS	Real tSMS stimulation.
Sham tSMS	Sham tSMS	Sham tSMS stimulation.

Primary Outcome Measures

Name	Time	Method
Nine-Hole Peg Test (9HPT)	5 minutes	Was used to assess finger dexterity; this tool has been used in the assessment of motor activity in a multitude of pathologies, with adequate to excellent inter-rater reliability and excellent inter-rater reliability in healthy adults.
Finger Tapping Test (FTT)	5 minutes	was performed for assessment of manual motor skills. This test has been used for many years in the neuropsychological assessment of brain damage, being an indicator of cortical activity, as well as being used in NIBS studies as a measure of manual dexterity.

Secondary Outcome Measures

Name	Time	Method
Hand grip strength	5 minutes	Upper extremity force production was assessed by grip testing; a hand-held dynamometer (Jamar Plus+; Sammons Preston, Rolyon, Bolingbrook, IL) was used for this purpose. Greater hand grip strength corresponds with greater activation in M1, premotor area (PMA), and supplementary motor area (SMA) in the dominant hemisphere, and of the SMA in the nondominant hemisphere, and may provide information about the functionality of the human brain.

Trial Locations

Locations (1)

Universidad Rey Juan Carlos; 🇪🇸 Alcorcón, Madrid, Spain