Non-invasive Cerebellar Stimulation on Motor Learning

Summary

A crossover trial with healthy volunteers will be conducted. Six sessions will be performed once a week in a counterbalanced order and at least with seven days washout period to minimize carry-over effects. In each session, volunteers will be submitted to: fatigue and attention levels evaluation, cortical brain activity measures through paired pulse transcranial magnetic stimulation (pp-TMS), handwriting test, non-invasive cerebellar stimulation during serial reaction time task (SRTT) and performance perception evaluation.

Conditions

• Healthy

Interventions

DEVICE

tDCS

Current will be applied by a DC stimulator (NeuroConn Plus, Germany).The active electrode (anode: 5x5 cm²) will be placed over the left cerebellar hemisphere (3 cm lateral to the inion) and the reference (5x7 cm²), over the right arm with current intensity of 2mA, fade in and fade out of 10 seconds, during 20 minutes.

DEVICE

tDCS

Current will be applied by a DC stimulator (NeuroConn Plus, Germany). The active electrode (cathode: 5x5 cm²) will be placed over the left cerebellar hemisphere (3 cm lateral to the inion) and the reference (5x7 cm²), over the right arm with current intensity of 2mA, fade in and fade out of 10 seconds, during 20 minutes.

DEVICE

tDCS

Sham ctDCS will be applied using the same electrodes placement and parameter settings of cathodal ctDCS. However, stimulation will last only 30 seconds but volunteers will be with electrodes montage for 20 minutes.

DEVICE

rTMS

High frequency c-rTMS will be applied through a figure-eight coil connected to a magnetic stimulator (Rapid², Magstim, UK) placed over the left cerebellar hemisphere (3 cm lateral to the inion), tangentially to the scalp and pointing upwards. Protocol: 10Hz, 110% RMT, 33 trains, 50 stimuli per train, intertrain interval of 25 seconds, 1650 stimuli.

DEVICE

rTMS

Low frequency c-rTMS will be applied through a figure-eight coil connected to a magnetic stimulator (Rapid², Magstim, UK) placed over the left cerebellar hemisphere (3 cm lateral to the inion), tangentially to the scalp and pointing upwards. Protocol: 1Hz, 110% RMT, 1000 stimuli (1 train).

DEVICE

rTMS

Sham c-rTMS will be performed with low frequency protocol using two coils. The first one - connected to the stimulator (Rapid², Magstim, UK) - will be positioned on a coil support close to the volunteer but not visible. Therefore, characteristic stimulation noises will be audible. The second - disconnected to the stimulator - will be placed over left cerebellar hemisphere.

DEVICE

pp-TMS assessment

SICI and ICF will be evaluated through pp-TMS. Subthreshold conditioning stimuli (80% of RMT) and suprathreshold test stimuli (120% of RMT) will be delivered at 2 milliseconds ISI, in order to determine SICI. ICF will be evaluated by MEP average at an ISI of 10 milliseconds. Ten stimuli will be applied at each condition (unconditioned pulse and pairs of stimuli with ISI of 2 and 10 milliseconds). Stimuli order delivery will be pseudo-randomized and SICI and ICF will be expressed as conditioned stimulus percentage regarding an unconditioned stimulus.

Sponsors & Collaborators

• Universidade Federal de Pernambuco

  lead OTHER

Principal Investigators

• Kátia K Monte-Silva, PhD · Universidade Federal de Pernambuco

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

40 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2015-09-30

Primary Completion

2016-08-31

Completion

2016-09-30

Countries

• Brazil

Study Locations