scholarly journals Optimal Combination of Anodal Transcranial Direct Current Stimulations and Motor Imagery Interventions

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Elodie Saruco ◽  
Franck Di Rienzo ◽  
Susana Nunez-Nagy ◽  
Miguel A. Rubio-Gonzalez ◽  
Ursula Debarnot ◽  
...  
Keyword(s):  
Postural Control ◽  
Motor Imagery ◽  
Direct Current ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Homeostatic Plasticity ◽  
Experimental Conditions ◽  
Beneficial Effects ◽  
Imagery Training ◽  
Before And After

Motor imagery contributes to enhance the (re)learning of motor skills through remapping of cortical networks. Combining motor imagery with anodal transcranial direct-current stimulation (a-tDCS) over the primary motor cortex has further been shown to promote its beneficial effects on postural control. Whether motor imagery should be performed concomitantly to a-tDCS (over depolarized membrane) or consecutively (over changing neurotransmitters activity) remains to be elucidated. In the present study, we measured the performance in a postural control task before and after three experimental conditions. Participants received a-tDCS before (tDCSBefore), during (tDCSDuring), or both before and during motor imagery training (tDCSBefore + During). Performance was improved after tDCSDuring, but not after both the tDCSBefore and tDCSBefore + During conditions. These results support that homeostatic plasticity is likely to operate following a-tDCS through decreasing cortical excitability and that motor imagery should be performed during anodal stimulation for optimum gains.

scholarly journals Transcranial direct current stimulation treatment protocols: should stimulus intensity be constant or incremental over multiple sessions?

2013 ◽  
Vol 16 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Verònica Gálvez ◽  
Angelo Alonzo ◽  
Donel Martin ◽  
Colleen K. Loo
Keyword(s):  
Motor Cortex ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Constant Intensity ◽  
Treatment Protocols ◽  
Direct Current Stimulation ◽  
Before And After

Abstract Interest in transcranial direct current stimulation (tDCS) as a new tool in neuropsychiatry has led to the need to establish optimal treatment protocols. In an intra-individual randomized cross-over design, 11 healthy volunteers received five tDCS sessions to the left primary motor cortex on consecutive weekdays at a constant or gradually increasing current intensity, in two separate weeks of testing. Cortical excitability was assessed before and after tDCS at each session through peripheral electromyographic recordings of motor-evoked potentials. Both conditions led to significant cumulative increases in cortical excitability across the week but there were no significant differences between the two groups. Motor thresholds decreased significantly from Monday to Friday in both conditions. This study demonstrated that, in the motor cortex, administration of tDCS five times per week whether at a constant intensity or at a gradually increasing intensity was equally effective in increasing cortical excitability.

scholarly journals An acute session of motor imagery training induces use-dependent plasticity

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Célia Ruffino ◽  
Jérémie Gaveau ◽  
Charalambos Papaxanthis ◽  
Florent Lebon
Keyword(s):  
Motor Imagery ◽  
Primary Motor Cortex ◽  
Corticospinal Excitability ◽  
Movement Direction ◽  
Control Group ◽  
Dependent Plasticity ◽  
Imagery Training ◽  
Imagery Group ◽  
Before And After ◽  
The Right

AbstractMotor imagery, defined as the mental representation of an action without movement-related sensory inputs, is a well-known intervention to improve motor performance. In the current study, we tested whether use-dependent plasticity, a mechanism underlying motor learning, could be induced by an acute session of motor imagery. By means of transcranial magnetic stimulation (TMS) over the left primary motor cortex, we evoked isolated thumb movements in the right hand and assessed corticospinal excitability in the flexor and extensor pollicis brevis muscles. We measured the mean TMS-induced movement direction before and after an acute session of motor imagery practice. In a first experiment, participants of the imagery group were instructed to repeatedly imagine their thumb moving in a direction deviated by 90° from the pre-test movement. This group, but not the control group, deviated the post-training TMS-induced movements toward the training target direction (+44° ± 62° and −1° ± 23°, respectively). Interestingly, the deviation magnitude was driven by the corticospinal excitability increase in the agonist muscle. In a second experiment, we found that post-training TMS-induced movements were proportionally deviated toward the trained direction and returned to baseline 30 minutes after the motor imagery training. These findings suggest that motor imagery induces use-dependent plasticity and, this neural process is accompanied by corticospinal excitability increase in the agonist muscle.

scholarly journals An acute session of motor imagery training induces use-dependent plasticity

2019 ◽  
Author(s):  
Célia Ruffino ◽  
Jérémie Gaveau ◽  
Charalambos Papaxanthis ◽  
Florent Lebon
Keyword(s):  
Motor Imagery ◽  
Primary Motor Cortex ◽  
Corticospinal Excitability ◽  
Movement Direction ◽  
Control Group ◽  
Dependent Plasticity ◽  
Imagery Training ◽  
Imagery Group ◽  
Before And After ◽  
The Right

AbstractMotor imagery, defined as the mental representation of an action without movement-related sensory inputs, is a well-known intervention to improve motor performance. In the current study, we tested whether use-dependent plasticity, a mechanism underlying motor learning, could be induced by an acute session of motor imagery. By means of transcranial magnetic stimulation (TMS) over the left primary motor cortex, we evoked isolated thumb movements in the right hand and assessed corticospinal excitability in the flexor and extensor pollicis brevis muscles. We measured the mean TMS-induced movement direction before and after an acute session of motor imagery practice. In a first experiment, participants of the imagery group were instructed to repeatedly imagine their thumb moving in a direction deviated by 90° from the pre-test movement. This group, but not the control group, deviated the post-training TMS-induced movements toward the training target direction (+44° ±62° and −1° ±23°, respectively). Interestingly, the deviation magnitude was driven by the corticospinal excitability increase in the agonist muscle. In a second experiment, we found that post-training TMS-induced movements were proportionally deviated toward the trained direction and returned to baseline 30 minutes after the motor imagery training. These findings suggest that motor imagery induces use-dependent plasticity and, this neural process is accompanied by corticospinal excitability increase in the agonist muscle.

scholarly journals Anodal tDCS over the primary motor cortex improves motor imagery benefits on postural control: A pilot study

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Elodie Saruco ◽  
Franck Di Rienzo ◽  
Susana Nunez-Nagy ◽  
Miguel A. Rubio-Gonzalez ◽  
Philip L. Jackson ◽  
...  
Keyword(s):  
Pilot Study ◽  
Motor Cortex ◽  
Postural Control ◽  
Motor Imagery ◽  
Primary Motor Cortex ◽  
Anodal Tdcs

scholarly journals The effects of transcranial direct current stimulation on corticospinal and cortico-cortical excitability and response variability: conventional versus high-definition montages

2020 ◽  
Author(s):  
Michael Pellegrini ◽  
Maryam Zoghi ◽  
Shapour Jaberzadeh
Keyword(s):  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Short Interval ◽  
Individual Variability ◽  
Response Variability ◽  
Pulse Interval ◽  
Direct Current Stimulation

AbstractResponse variability following transcranial direct current stimulation (tDCS) highlights need for exploring different tDCS electrode montages. This study compared corticospinal excitability (CSE), cortico-cortical excitability and intra-individual variability following conventional and HD anodal (a-tDCS) and cathodal (c-tDCS) tDCS. Fifteen healthy young males attended four sessions at least one-week apart: conventional a-tDCS, conventional c-tDCS, HD-a-tDCS, HD-c-tDCS. TDCS was administered (1mA, 10-minutes) over the primary motor cortex (M1), via 6×4cm active and 7×5cm return electrodes (conventional tDCS) and 4×1 ring-electrodes 3.5cm apart in ring formation around M1 (HD-tDCS). For CSE, twenty-five single-pulse transcranial magnetic stimulation (TMS) peak-to-peak motor evoked potentials (MEP) were recorded at baseline, 0-minutes and 30-minutes post-tDCS. For cortico-cortical excitability, twenty-five paired-pulse MEPs with 3-millisecond (ms) inter-pulse interval (IPI) and twenty-five at 10ms assessed short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) respectively. MEP standardised z-values standard deviations represented intra-individual variability. No significant differences were reported in CSE between conventional and HD a-tDCS, but significant differences between conventional and HD c-tDCS 0-minutes post-tDCS. Intra-individual variability was significantly reduced in conventional tDCS compared to HD-tDCS for a-tDCS (0-minutes) and c-tDCS (30-minutes). No significant changes were reported in SICI and ICF. These novel findings highlight current technical issues with HD-tDCS, suggesting future tDCS studies should utilise conventional tDCS to minimise intra-individual variability, ensuring tDCS after-effects are true changes in CSE and cortico-cortical excitability.

scholarly journals Sensorized Assessment of Dynamic Locomotor Imagery in People with Stroke and Healthy Subjects

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4545
Author(s):  
Daniela De Bartolo ◽  
Valeria Belluscio ◽  
Giuseppe Vannozzi ◽  
Giovanni Morone ◽  
Gabriella Antonucci ◽  
...  
Keyword(s):  
Motor Imagery ◽  
Lower Limbs ◽  
Imagery Task ◽  
Experimental Conditions ◽  
Significant Information ◽  
Imagery Training ◽  
Mental Chronometry ◽  
Sinusoidal Waveform ◽  
Reaction Forces ◽  
Measurement Units

Dynamic motor imagery (dMI) is a motor imagery task associated with movements partially mimicking those mentally represented. As well as conventional motor imagery, dMI has been typically assessed by mental chronometry tasks. In this paper, an instrumented approach was proposed for quantifying the correspondence between upper and lower limb oscillatory movements performed on the spot during the dMI of walking vs. during actual walking. Magneto-inertial measurement units were used to measure limb swinging in three different groups: young adults, older adults and stroke patients. Participants were tested in four experimental conditions: (i) simple limb swinging; (ii) limb swinging while imagining to walk (dMI-task); (iii) mental chronometry task, without any movement (pure MI); (iv) actual level walking at comfortable speed. Limb swinging was characterized in terms of the angular velocity, frequency of oscillations and sinusoidal waveform. The dMI was effective at reproducing upper limb oscillations more similar to those occurring during walking for all the three groups, but some exceptions occurred for lower limbs. This finding could be related to the sensory feedback, stretch reflexes and ground reaction forces occurring for lower limbs and not for upper limbs during walking. In conclusion, the instrumented approach through wearable motion devices adds significant information to the current dMI approach, further supporting their applications in neurorehabilitation for monitoring imagery training protocols in patients with stroke.

scholarly journals Differences between motor execution and motor imagery of grasping movements in the motor cortical excitatory circuit

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5588 ◽  
Author(s):  
Hai-Jiang Meng ◽  
Yan-Ling Pi ◽  
Ke Liu ◽  
Na Cao ◽  
Yan-Qiu Wang ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Motor Imagery ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Short Interval ◽  
Corticospinal Excitability ◽  
Motor Execution ◽  
Human Motor Cortex ◽  
Motor Cortical ◽  
The Right

Background Both motor imagery (MI) and motor execution (ME) can facilitate motor cortical excitability. Although cortical excitability is modulated by intracortical inhibitory and excitatory circuits in the human primary motor cortex, it is not clear which intracortical circuits determine the differences in corticospinal excitability between ME and MI. Methods We recruited 10 young healthy subjects aged 18−28 years (mean age: 22.1 ± 3.14 years; five women and five men) for this study. The experiment consisted of two sets of tasks involving grasp actions of the right hand: imagining and executing them. Corticospinal excitability and short-interval intracortical inhibition (SICI) were measured before the interventional protocol using transcranial magnetic stimulation (baseline), as well as at 0, 20, and 40 min (T0, T20, and T40) thereafter. Results Facilitation of corticospinal excitability was significantly greater after ME than after MI in the right abductor pollicis brevis (APB) at T0 and T20 (p < 0.01 for T0, and p < 0.05 for T20), but not in the first dorsal interosseous (FDI) muscle. On the other hand, no significant differences in SICI between ME and MI were found in the APB and FDI muscles. The facilitation of corticospinal excitability at T20 after MI correlated with the Movement Imagery Questionnaire (MIQ) scores for kinesthetic items (Rho = −0.646, p = 0.044) but did not correlate with the MIQ scores for visual items (Rho = −0.265, p = 0.458). Discussion The present results revealed significant differences between ME and MI on intracortical excitatory circuits of the human motor cortex, suggesting that cortical excitability differences between ME and MI may be attributed to the activation differences of the excitatory circuits in the primary motor cortex.

scholarly journals Influence of Alternate Hot and Cold Thermal Stimulation in Cortical Excitability in Healthy Adults: An fMRI Study

2019 ◽  
Vol 9 (1) ◽  
pp. 18 ◽  
Author(s):  
Sharon Chia-Ju Chen ◽  
Jau-Hong Lin ◽  
Jui-Sheng Hsu ◽  
Chiu-Ming Shih ◽  
Jui-Jen Lai ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Stroke Rehabilitation ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Healthy Adults ◽  
Thermal Stimulation ◽  
Cortical Activation ◽  
Thermal Testing ◽  
Cold Pain ◽  
Before And After

Stroke rehabilitation using alternate hot and cold thermal stimulation (altTS) has been reported to improve motor function in hemiplegia; however, the influence of brain excitability induced by altTS remains unclear. This study examined cortical activation induced by altTS in healthy adults, focusing on motor-related areas. This involved a repeated crossover experimental design with two temperature settings (innocuous altTS with alternate heat-pain and cold-pain thermal and noxious altTS with alternate heat and cold thermal) testing both arms (left side and right side). Thirty-one healthy, right-handed participants received four episodes of altTS on four separate days. Functional magnetic resonance imaging scans were performed both before and after each intervention to determine whether altTS intervention affects cortical excitability, while participants performed a finger-tapping task during scanning. The findings revealed greater response intensity of cortical excitability in participants who received noxious altTS in the primary motor cortex, supplementary motor cortex, and somatosensory cortex than in those who received innocuous altTS. Moreover, there was more motor-related excitability in the contra-lateral brain when heat was applied to the dominant arm, and more sensory-associated excitability in the contra-lateral brain when heat was applied to the nondominant arm. The findings highlight the effect of heat on cortical excitability and provide insights into the application of altTS in stroke rehabilitation.

scholarly journals Evaluating Aftereffects of Short-Duration Transcranial Random Noise Stimulation on Cortical Excitability

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Leila Chaieb ◽  
Walter Paulus ◽  
Andrea Antal
Keyword(s):  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Random Noise ◽  
Single Pulse ◽  
Corticospinal Excitability ◽  
After Effects ◽  
Transcranial Random Noise Stimulation ◽  
Before And After ◽  
Baseline Levels ◽  
Minimal Stimulation

A 10-minute application of highfrequency (100–640 Hz) transcranial random noise stimulation (tRNS) over the primary motor cortex (M1) increases baseline levels of cortical excitability, lasting around 1 hr poststimulation Terney et al. (2008). We have extended previous work demonstrating this effect by decreasing the stimulation duration to 4, 5, and 6 minutes to assess whether a shorter duration of tRNS can also induce a change in cortical excitability. Single-pulse monophasic transcranial magnetic stimulation (TMS) was used to measure baseline levels of cortical excitability before and after tRNS. A 5- and 6-minute tRNS application induced a significant facilitation. 4-minute tRNS produced no significant aftereffects on corticospinal excitability. Plastic after effects after tRNS on corticospinal excitability require a minimal stimulation duration of 5 minutes. However, the duration of the aftereffect of 5-min tRNS is very short compared to previous studies using tRNS. Developing different transcranial stimulation techniques may be fundamental in understanding how excitatory and inhibitory networks in the human brain can be modulated and how each technique can be optimised for a controlled and effective application.

scholarly journals Motor imagery practice during arm-immobilization benefits sensorimotor cortical functions and plasticity-related sleep features

2019 ◽  
Author(s):  
Ursula Debarnot ◽  
Aurore. A. Perrault ◽  
Virginie Sterpenich ◽  
Guillaume Legendre ◽  
Chieko Huber ◽  
...  
Keyword(s):  
Motor Cortex ◽  
Motor Imagery ◽  
Rem Sleep ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Neural Mechanisms ◽  
Sleep Spindles ◽  
Cortical Representations ◽  
Cortical Functions

ABSTRACTMotor imagery (MI) is known to engage motor networks and could compensate for the maladaptive neuroplasticity elicited by immobilization. This hypothesis and associated underlying neural mechanisms remain underexplored. Here, we investigated how MI practice during 11 h of arm-immobilization influences sensorimotor and cortical representations of the hands, as well as sleep. Fourteen participants were first tested after a normal day, followed by two 11-h periods of immobilization, either with concomitant MI treatment or control tasks. Data revealed that MI prevented the consequences of immobilization: (i) alteration of the sensorimotor representation of hands, (ii) decrease of cortical excitability over the primary motor cortex (M1) contralateral to arm-immobilization, and (iii) reduction of sleep spindles over both M1s. Furthermore, (iv) the time spent in REM sleep was significantly longer after MI. These results support that implementing MI during immobilization can limit the deleterious effects of limb disuse, at several levels of sensorimotor functioning.

Sign in / Sign up

Export Citation Format

Share Document