Safety Study Based on Transcranial Electrical Stimulation in Chile: a Case Series Study

Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation technique that delivers low-intensity, direct current to cortical areas facilitating or inhibiting spontaneous neuronal activity. It has been used to improve cognitive functions such as memory, language, and attention. Research has also shown that tDCS on motor cortex can improve motor performance.

TDCS secondary effects have been measured in several studies. The most frequent secondary effects described in literature are a mild tingling sensation, moderate fatigue, itching sensation, slight burning and mild pain sensation under the electrodes during the stimulation.

The present study is focused in evaluate the safety of a transcranial direct current stimulation (TDCS) service by measuring secondary effects incidence in a group of healthy subjects. In addition, manual dexterity and upper limb strength will be measure to identify improvement in motor performance after intervention.

Study Overview

• Status: Unknown
• Conditions: Healthy Subjects
• Intervention / Treatment: Device: Multi-channel Transcranial direct current stimulation

Detailed Description

Transcranial electrical stimulation (tES) is a neurophysiological technique capable of modulating the excitability of the neuronal tissue of the central and peripheral nervous system through the application, for a finite time length, of an electrical field. This electric field is generated by the application of weak electrical currents through the scalp and into the brain. It has been demonstrated in recent years that the technique is safe and beneficial if used within the known bounds of intensity, density and duration.

The tES technique is classified into three types according to the waveform of the stimulation current that is applied: Transcranial direct current stimulation (tDCS),Transcranial Alternating Current Stimulation (tACS) and Transcranial random noise stimulation (tRNS). Additionally, the Sham mode can be used for controlled experiments.

TDCS is a neuromodulatory technique that delivers low-intensity, direct current to cortical areas facilitating or inhibiting spontaneous neuronal activity. In general, the current is injected into the brain (anodal stimulation) over a cortical region leading to excitatory effects; and collected from the brain (cathodal stimulation) leading to inhibitory effects. tDCS produces short term effects on neuronal excitability, and long lasting plastic after/effects involving synaptic modification.

Research has shown that applying anodal tDCS to the non-dominant motor cortex can improve motor performance for the non-dominant hand, presumably by means of changes in synaptic plasticity between neurons. Other studies suggest improvement on cognitive functions such as memory, language, and attention after a tDCS program.

TDCS secondary effects have been measured in several studies. The most frequent secondary effects described in literature are a mild tingling sensation, moderate fatigue, itching sensation, slight burning and mild pain sensation under the electrodes during the stimulation. A visual sensation, associated with switching on and off the stimulation, have been also described. Less frequent are the difficulties in concentrating, headache, felt nervous or overexcited and nausea after the stimulation.

The present study is focused in evaluate the safety of a TDCS pilot program by measuring secondary effects incidence in a group of healthy subjects. In addition, manual dexterity and upper limb strength will be measure to identify improvement in motor performance after intervention.

• Study Type: Interventional
• Enrollment (Anticipated): 3
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Chile
  • XII Región
    • Punta Arenas, XII Región, Chile, 6211525
      • Corporación de Rehabilitación Club de Leones Cruz del Sur

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Healthy subjects
• Both gender
• Informed consent accepted
• Adults

Exclusion Criteria:

• Neurological diseases
• Mental diseases
• Injuries in the scalp skin
• Inflammatory tegumentary diseases
• Migraines
• Medication or substances affecting central nervous system
• Presence of chronic diseases
• Presence of degenerative diseases
• Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

EXPERIMENTAL: Transcranial Direct Current Stimulation; Each subject will receive transcranial electrical stimulation at primary motor cortex in both hemispheres. The pilot program will include 12 sessions with a frequency of 3 times per week during 4 weeks. Therefore, during tDCS sessions, subjects will receive stimulation for 20 minutes with a current of 2.0 milliamp using 6x4 cm electrodes. The participants will also complete a set of manual dexterity, grip and pinch tests bilaterally at baseline and post-intervention to determine if the subject responds to tDCS. Thus, each session will be monitored on safety aspects of the subjects with emphasis on skin disorders and other possible side effects of tDCS.

Device: Multi-channel Transcranial direct current stimulation; A commercial tDCS device will be use in this study. The device is a wireless multi-channel transcranial direct current stimulator that incorporates an 8-channel headcap for stimulation through gel electrodes or classic sponge electrodes. The device is integrated with a user interface for the configuration and monitoring of the stimulus parameters and a fast multifocal simulation of the tDCS electric field using an advanced brain model

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change of block and box test score	Change of the Box and Block test score, it's a measure of the number of blocks the subject can move in 1 minute, between the beginning (T0) and immediately after the end of treatment (T1). Range of score 0-120. A positive change represents improved performance on Box and Blocks test.	Baseline, 4 weeks
Change of Side effect checklist for transcranial direct current stimulation	A checklist that records side effect after TDCS sessions including fatigue, headache or dizziness, nausea, and a itching sensation in the stimulation area.	Baseline, 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change of nine hole peg test score	The Nine Hole Pegs technique is a simple manual dexterity test, commonly used in ergotherapy. The participant tries to place 9 pegs in a 9 holes perforated plate, and then tries to remove them as quickly as possible. The hand must stay in a depression within the plate, thereby insuring a constant distance between the hand and the pegs.	Baseline, 4 weeks
Change of grip strength measurement	Change of value of kilogram - force (kgf) measured with a handheld dynamometer on a single grip test of maximum contraction for 3 seconds.	Baseline, 4 weeks
Change of pinch strength measurement	Change of value of kilogram - force (kgf) measured with a handheld dynamometer on a single pinch test of maximum contraction for 3 seconds.	Baseline, 4 weeks

Collaborators and Investigators

• Sponsor: Corporación de Rehabilitación Club de Leones Cruz del Sur
• Investigators: Principal Investigator: Karim S Baleta Abarza, Lic., Corporación de Rehabilitación Club de Leones Cruz del Sur

Publications and helpful links

General Publications

• Brunoni AR, Nitsche MA, Bolognini N, Bikson M, Wagner T, Merabet L, Edwards DJ, Valero-Cabre A, Rotenberg A, Pascual-Leone A, Ferrucci R, Priori A, Boggio PS, Fregni F. Clinical research with transcranial direct current stimulation (tDCS): challenges and future directions. Brain Stimul. 2012 Jul;5(3):175-195. doi: 10.1016/j.brs.2011.03.002. Epub 2011 Apr 1.
• Vines BW, Cerruti C, Schlaug G. Dual-hemisphere tDCS facilitates greater improvements for healthy subjects' non-dominant hand compared to uni-hemisphere stimulation. BMC Neurosci. 2008 Oct 28;9:103. doi: 10.1186/1471-2202-9-103.
• Almousa A, Alajaji R, Alaboudi M, Al-Sultan F, Bashir S. Safety of Transcranial Direct Current Stimulation of Frontal, Parietal, and Cerebellar Regions in Fasting Healthy Adults. Behav Sci (Basel). 2018 Sep 10;8(9):81. doi: 10.3390/bs8090081.
• Paulus W. Transcranial electrical stimulation (tES - tDCS; tRNS, tACS) methods. Neuropsychol Rehabil. 2011 Oct;21(5):602-17. doi: 10.1080/09602011.2011.557292. Epub 2011 Aug 5.

Study record dates

Study Major Dates

• Study Start (ACTUAL): December 1, 2019
• Primary Completion (ANTICIPATED): December 31, 2021
• Study Completion (ANTICIPATED): December 31, 2021

Study Registration Dates

• First Submitted: January 22, 2020
• First Submitted That Met QC Criteria: January 25, 2020
• First Posted (ACTUAL): January 28, 2020

Study Record Updates

• Last Update Posted (ACTUAL): November 5, 2020
• Last Update Submitted That Met QC Criteria: November 3, 2020
• Last Verified: November 1, 2020

More Information

Terms related to this study

• Keywords: transcranial direct current stimulation; motor cortex; transcranial electrical stimulation; motor performance; secondary effects
• Other Study ID Numbers: CorporacionRCLCS0002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No