Search results for "Transcranial"

Effects of low-gamma tACS on primary motor cortex in implicit motor learning

2019

Abstract In the primary motor cortex (M1), rhythmic activity in the gamma frequency band has been found during movement planning, onset and execution. Although the role of high-gamma oscillatory activity in M1 is well established, the contribution of low-gamma activity is still unexplored. In this study, transcranial alternating current stimulation (tACS) was used with the aim to specifically modulate low-gamma frequency band in M1, during an implicit motor learning task. A 40 Hz-tACS was applied over the left M1 while participants performed a serial reaction time task (SRTT) using their right hand. The task required the repetitive execution of sequential movements in response to sequences …

Interference of left and right cerebellar rTMS with procedural learning.

2004

Abstract Increasing evidence suggests cerebellar involvement in procedural learning. To further analyze its role and to assess whether it has a lateralized influence, in the present study we used a repetitive transcranial magnetic stimulation interference approach in a group of normal subjects performing a serial reaction time task. We studied 36 normal volunteers: 13 subjects underwent repetitive transcranial magnetic stimulation on the left cerebellum and performed the task with the right (6 subjects) or left (7 subjects) hand; 10 subjects underwent repetitive transcranial magnetic stimulation on the right cerebellum and performed the task with the hand ipsilateral (5 subjects) or contral…

The role of the dorsolateral prefrontal cortex in implicit procedural learning.

1996

We studied the role of the dorsolateral prefrontal cortex in procedural learning. Normal subjects completed several blocks of a serial reaction time task using only one hand without or with concurrent non-invasive repetitive transcranial magnetic stimulation. To disrupt their function transiently, stimulation was applied at low intensity over the supplementary motor area or over the dorsolateral prefrontal cortex contralateral or ipsilateral to the hand used for the test. Stimulation to the contralateral dorsolateral prefrontal cortex markedly impaired procedural implicit learning, as documented by the lack of significant change in response times during the task. Stimulation over the other …

Functional Role of Cerebellar Gamma Frequency in Motor Sequences Learning: a tACS Study

2021

Although the role of the cerebellum in motor sequences learning is widely established, the specific function of its gamma oscillatory activity still remains unclear. In the present study, gamma (50 Hz)—or delta (1 Hz)—transcranial alternating current stimulation (tACS) was applied to the right cerebellar cortex while participants performed an implicit serial reaction time task (SRTT) with their right hand. The task required the execution of motor sequences simultaneously with the presentation of a series of visual stimuli. The same sequence was repeated across multiple task blocks (from blocks 2 to 5 and from blocks 7 to 8), whereas in other blocks, new/pseudorandom sequences were reproduce…

Transcranial magnetic stimulation and neuroplasticity

1998

We review past results and present novel data to illustrate different ways in which TMS can be used to study neural plasticity. Procedural learning during the serial reaction time task (SRTT) is used as a model of neural plasticity to illustrate the applications of TMS. These different applications of TMS represent principles of use that we believe are applicable to studies of cognitive neuroscience in general and exemplify the great potential of TMS in the study of brain and behavior. We review the use of TMS for (1) cortical output mapping using focal, single-pulse TMS; (2) identification of the mechanisms underlying neuroplasticity using paired-pulse TMS techniques; (3) enhancement of th…

2018

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that allows the modulation of cortical excitability as well as neuroplastic reorganization using a weak constant current applied through the skull on the cerebral cortex. TDCS has been found to improve motor performance in general and motor learning in particular. However, these effects have been reported almost exclusively for unimanual motor tasks such as serial reaction time tasks, adaptation tasks, or visuo-motor tracking. Despite the importance of bimanual actions in most activities of daily living, only few studies have investigated the effects of tDCS on bimanual motor skills. The objectives …

Use of noninvasive cerebral stimulation techniques in aphasia: An updating

2012

Aphasia is a receptive and expressive communication disorder following to a cerebral accident (stroke, head injury, tumor). ical speech and language therapy was not able to significantly contribute to the aphasia recovery. In the last decade two nonin- vasive cerebral techniques, transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have been used for the treatment of aphasic patients. In this paper I will report some of the main results in this field. The aim is to highlight both coherent and contrasting outcomes emerging from the use of these techniques and to understand their therapeutic potential in the treatment of aphasia.

Overestimation of numerical distances in the left space

2004

Normal subjects presented with a middle number and two left- and right-sided outer numbers overestimate the numerical distance between the middle number and that positioned at its left side. Repetitive transcranial magnetic stimulation (rTMS) of the right posterior parietal cortex specifically counteracts this bias, suggesting that the mental representation of space defined by numbers is shifted toward the left side depending on a greater activity of the right hemisphere.

Subfrontal approaches

2010

Among the different transcranial approaches routinely used for the management of anterior cranial base lesions, the subfrontal approach is one of the most common and versatile surgical procedures, with the unilateral or bilateral alternative, according to the lesion's extension and size. © 2010 Springer-Verlag Milan.

Is trans-cranial MR-guided Focused UltraSound a repeatable treatment option? Report of a successfully re-treated patient

2018

Background: In recent years, transcranial Magnetic Resonance-guided Focused UltraSounds (tcMRgFUS) treatments for functional neurological disorders are giving a new thrust to the field of therapeutic brain lesioning. This technique has been proven safe and effective in selected patients. Here we present the case of a patient affected by tremor combined with parkinsonism who underwent a second tcMRgFUS thalamotomy because of relapsing tremor after a few months from the first tcMRgFUS treatment. Materials and Methods: A 72-year-old, right-handed man, who came to our observation because of a disabling tremor affecting mainly his upper right limb and refusing any invasive surgical procedure. Hi…