Search results for "Motor cortex"

CMC is more than a measure of corticospinal tract integrity in acute stroke patients

2021

In healthy subjects, motor cortex activity and electromyographic (EMG) signals from contracting contralateral muscle show coherence in the beta (15-30 Hz) range. Corticomuscular coherence (CMC) is considered a sign of functional coupling between muscle and brain. Based on prior studies, CMC is altered in stroke, but functional significance of this finding has remained unclear. Here, we examined CMC in acute stroke patients and correlated the results with clinical outcome measures and corticospinal tract (CST) integrity estimated with diffusion tensor imaging (DTI). During isometric contraction of the extensor carpi radialis muscle, EMG and magnetoencephalographic oscillatory signals were re…

Brain Modulation by Electric Currents in Fibromyalgia: A Structured Review on Non-invasive Approach With Transcranial Electrical Stimulation

2018

Fibromyalgia syndrome (FMS) is a complex disorder where widespread musculoskeletal pain is associated with many heterogenous symptoms ranging from affective disturbances to cognitive dysfunction and central fatigue. FMS is currently underdiagnosed and often very poorly responsive to pharmacological treatment. Pathophysiology of the disease remains still obscure even if in the last years fine structural and functional cerebral abnormalities have been identified, principally by neurophysiological and imaging studies delineating disfunctions in pain perception, processing and control systems. On such basis, recently, neurostimulation of brain areas involved in mechanism of pain processing and …

Modulation of Human Motor Cortical Excitability and Plasticity by Opuntia Ficus Indica Fruit Consumption: Evidence from a Preliminary Study through N…

2022

Indicaxanthin (IX) from Opuntia Ficus Indica (OFI) has been shown to exert numerous biological effects both in vitro and in vivo, such as antioxidant, anti-inflammatory, neuro-modulatory activity in rodent models. Our goal was to investigate the eventual neuro-active role of orally assumed fruits containing high levels of IX at nutritionally-relevant amounts in healthy subjects, exploring cortical excitability and plasticity in the human motor cortex (M1). To this purpose, we applied paired-pulse transcranial magnetic stimulation and anodal transcranial direct current stimulation (a-tDCS) in basal conditions and followed the consumption of yellow cactus pear fruits containing IX or white ca…

Neurophysiological Changes After Paired Brain and Spinal Cord Stimulation Coupled With Locomotor Training in Human Spinal Cord Injury

2021

Neurophysiological changes that involve activity-dependent neuroplasticity mechanisms via repeated stimulation and locomotor training are not commonly employed in research even though combination of interventions is a common clinical practice. In this randomized clinical trial, we established neurophysiological changes when transcranial magnetic stimulation (TMS) of the motor cortex was paired with transcutaneous thoracolumbar spinal (transspinal) stimulation in human spinal cord injury (SCI) delivered during locomotor training. We hypothesized that TMS delivered before transspinal (TMS-transspinal) stimulation promotes functional reorganization of spinal networks during stepping. In this p…

Modulation of plasticity of the soleus area of the motor cortex using paired associative stimulation

2015

Paired associative stimulation (PAS) repeatedly combines single somatosensory nerve stimuli with single transcranial magnetic stimuli to induce bidirectional changes in the excitability of the cortical projections to the target muscle. PAS and motor training have been shown to share common neural mechanisms, suggesting that PAS tests functionally relevant neuronal circuits. While PAS has been used extensively to target the hand area of the motor cortex, few studies have targeted the leg area of the motor cortex. The optimal interstimulus inter- val (ISI) to induce plasticity in the cortical projections to lower limbs is still not well established. Thus, the first purpose of this thesis was …

Individualized Template MRI Is a Valid and Reliable Alternative to Individual MRI for Spatial Tracking in Navigated TMS Studies in Healthy Subjects

2020

Objectives: Navigated transcranial magnetic stimulation (nTMS) provides significant benefits over classic TMS. Yet, the acquisition of individual structural magnetic resonance images (MRIindividual) is a time-consuming, expensive, and not feasible prerequisite in all subjects for spatial tracking and anatomical guidance in nTMS studies. We hypothesize that spatial transformation can be used to adjust MRI templates to individual head shapes (MRIwarped) and that TMS parameters do not differ between nTMS using MRIindividual or MRIwarped.Materials and Methods: Twenty identical TMS sessions, each including four different navigation conditions, were conducted in 10 healthy subjects (one female, 2…

Prismatic adaptation modulates oscillatory EEG correlates of motor preparation but not visual attention in healthy participants

2018

Prismatic adaption (PA) has been proposed as a tool to induce neural plasticity and is used to help neglect rehabilitation. It leads to a recalibration of visuo-motor coordination during pointing as well as to after-effects on a number of sensorimotor and attention tasks, but whether these effects originate at a motor or attentional level remains a matter of debate. Our aim was to further characterise PA after-effects by using an approach that allows distinguishing between effects on attentional and motor processes. We recorded electroencephalography (EEG) in healthy human participants (9 females and 7 males) while performing a new double step, anticipatory attention/motor preparation parad…

Are paradoxical intensity-dependent effects of 5Hz rTMS train in motor cortex of migraine with aura patients evidence of abnormal homeostatic plastic…

2010

Effects of High-Definition Anodal Transcranial Direct Current Stimulation Applied Simultaneously to Both Primary Motor Cortices on Bimanual Sensorimo…

2017

Many daily activities, such as tying one’s shoe laces, opening a jar of jam or performing a free throw in basketball, require the skillful coordinated use of both hands. Even though the non-invasive method of transcranial direct current stimulation (tDCS) has been repeatedly shown to improve unimanual motor performance, little is known about its effects on bimanual motor performance. More knowledge about how tDCS may improve bimanual behavior would be relevant to motor recovery, e.g., in persons with bilateral impairment of hand function. We therefore examined the impact of high-definition anodal tDCS (HD-atDCS) on the performance of a bimanual sequential sensorimotor task. Thirty-two volun…

Transcranial Alternating Current Stimulation (tACS) Does Not Affect Sports People’s Explosive Power: A Pilot Study

2021

Purpose: This study is aimed to preliminary investigate whether transcranial alternating current stimulation (tACS) could affect explosive power considering genetic background in sport subjects.Methods: Seventeen healthy sports volunteers with at least 3 years of sports activities participated in the experiment. After 2 weeks of familiarization performed without any stimulation, each participant received either 50 Hz-tACS or sham-tACS. Before and after stimulation, subjects performed the following tests: (1) the squat jump with the hands on the hips (SJ); (2) countermovement jump with the hands on the hips (CMJ); (3) countermovement jump with arm swing (CMJ-AS); (4) 15-s Bosco’s test; (5) s…