Search results for "STIMULATION"
showing 10 items of 2192 documents
TRANSCRANIAL DIRECT CURRENT STIMULATION ENHANCES SUCKING OF A LIQUID BOLUS IN HEALTHY HUMANS
2014
Abstract Background Transcranial direct current stimulation (tDCS) is a non-invasive technique used for modulating cortical excitability in vivo in humans. Here we evaluated the effect of tDCS on behavioral and electrophysiological aspects of physiological sucking and swallowing. Methods Twelve healthy subjects underwent three tDCS sessions (anodal, cathodal and sham stimulation) on separate days in a double-blind randomized order. The active electrode was placed over the right swallowing motor cortex. Repeated sucking and swallowing acts were performed at baseline and at 15 and 60 min after each tDCS session and the mean liquid bolus volume ingested at each time point was measured. We also…
Magnetic stimulation study during observation of motor tasks.
2000
The aim of the study was to assess if the observation of single or more complex muscle movements activates the premotor cortex in man. We stimulated by transcranial magnetic stimulation the right and left motor cortex recording from the abductor pollicis brevis of eight normal subjects, during observation of different movements performed by the examiner: (1) single movements: thumb abduction, arm elevation; (2) motor sequences: finger opposing movements performed in an ordinate sequence: 1-2, 1-3, 1-4, 1-5, 1-2ellipsis, and in a non-consecutive non-repetitive order: 1-3, 1-5, 1-4, 1-2, 1-5, 1-2ellipsis We found an increased excitability of the right cortex during observation of isolated mus…
Prefrontal and temporo-parietal involvement in taking others' perspective: TMS evidence.
2008
INTRODUCTION: Understanding the mental states of others entails a number of cognitive processes known as Theory of Mind (ToM). Behavioural and functional neuroimaging evidence suggests that prefrontal and temporo-parietal cortices are involved in these abilities. The present study was aimed at investigating the role of the dorsolateral prefrontal cortex and temporo-parietal junction in ToM by using a repetitive transcranial magnetic stimulation (rTMS) paradigm. MATERIAL AND METHODS: Eleven healthy subjects participated in the study. The experimental ToM procedure was constituted by false belief and faux-pas written stories. Subjects were evaluated in baseline condition (Sham) and after 1Hz …
Modulation of spinal cord excitability by subthreshold repetitive transcranial magnetic stimulation of the primary motor cortex in humans.
2001
Repetitive transcranial magnetic stimulation (rTMS) allows the modulation of intra-cortical excitability and may therefore affect the descending control of spinal excitability. We applied rTMS at subthreshold intensity and 1 Hz frequency for 10 min to the left primary motor cortex representation of the flexor carpi radialis muscle (FCR) in 10 subjects and assessed the H and M responses to median nerve stimulation before and after the rTMS. Following rTMS, H wave thresholds significantly reduced by ∼20%. Maximal H but not M wave amplitude significantly increased over the baseline, so that H/M amplitude ratio was increased by 41%. Sham stimulation did not induce any noticeable change in M or …
Lateralized effects of self-induced sadness and happiness on corticospinal excitability.
1997
We studied the changes in excitability of the corticospinal projection evoked by self-induced sad and happy thoughts. Corticospinal excitability was probed using focal, single-pulse transcranial magnetic stimulation (TMS) applied to the optimal scalp position for evoking motor potentials in the contralateral first dorsal interosseus muscle. Fourteen right-handed subjects were studied while counting mentally, thinking sad thoughts, or thinking happy thoughts. In each of these three conditions TMS was applied in each subject randomly, 20 times to the right and 20 times to the left hemisphere. Sad thoughts resulted in a significant facilitation of the motor potentials evoked by left-hemispheri…
Analysis of cytokine and specific antibody profiles in hydatid patients with primary infection and relapse of disease
1998
We studied in vitro cytokine production by peripheral blood mononuclear cells (PBMC) from patients with primary and recurrent hydatid disease when cells were incubated with mitogen (PHA) and antigen from hydatid cyst fluid (HCFAg); levels of specific IgE, IgG4 and eosinophil counts were also measured in sera. When specifically stimulated, PBMC from patients produced higher levels of IL-2 (P < 0.02), IFN-γ (P < 0.0028) and IL-5 (P < 0.01) than those from uninfected donors, whereas IL-10 levels were comparable. Notably, IL-5 was also produced in higher levels (P < 0.01) by PBMC from patients when incubated with PHA. The IL-5:IFN-γ ratio was significantly greater (P < 0.02) when measured in re…
High-Frequency Transcranial Magnetic Stimulation on Motor Cortex of Patients Affected by Migraine With Aura: A Way to Restore Normal Cortical Excitab…
2009
We showed reduced motor intracortical inhibition (ICI) and paradoxical increase of intracortical facilitation (ICF) to 1 Hz repetitive transcranial magnetic stimulation (rTMS) in patients affected by migraine with aura (MA). In conditions of enhanced excitability due to a reduced inhibition, high-frequency rTMS was found to potentiate intracortical inhibition. Here we explored the conditioning effects of high-frequency priming stimulation of motor cortex with the aim of normalizing excitability reverting paradoxical facilitation by 1 Hz rTMS in MA. Nine patients with MA and nine healthy controls underwent a paired-pulse TMS paradigm to evaluate motor intracortical excitability (ICI and ICF…
Degree of Postictal Suppression Depends on Seizure Induction Time in Magnetic Seizure Therapy and Electroconvulsive Therapy.
2017
OBJECTIVES Anesthesia is required for both magnetic seizure therapy (MST) and electroconvulsive therapy (ECT), although it has anticonvulsant properties. In this case, bispectral index (BIS) monitoring, a specific electroencephalogram-derived monitoring, can be used to find the optimal seizure induction time during anesthesia to elicit adequate seizures. A measurement of seizure adequacy in electroencephalogram is the postictal suppression. The purpose of this study was to investigate the influence of seizure induction time on the degree of postictal suppression by comparing BIS versus no-BIS monitoring in MST and ECT. METHODS Twenty patients with treatment-resistant depression were randoml…
Recognition memory and prefrontal cortex: Dissociating recollection and familiarity processes using rTMS
2008
Recognition memory can be supported by both the assessment of the familiarity of an item and by the recollection of the context in which an item was encountered. The neural substrates of these memory processes are controversial. To address these issues we applied repetitive transcranial magnetic stimulation (rTMS) over the right and left dorsolateral prefrontal cortex (DLPFC) of healthy subjects performing a remember/know task. rTMS disrupted familiarity judgments when applied before encoding of stimuli over both right and left DLPFC. rTMS disrupted recollection when applied before encoding of stimuli over the right DLPFC. These findings suggest that the DLPFC plays a critical role in recog…
High frequency repetitive transcranial magnetic stimulation (rTMS) reduces EEG-hypofrontality in patients with schizophrenia.
2015
The reduced metabolic activity in the prefrontal brain lobes, so-called hypofrontality, is associated with increased electrophysiological delta-band activity. Schizophrenia inpatients (N=35) received sham-controlled 10Hz rTMS over the left dorsolateral prefrontal cortex in a randomised design. After treatment, the resting electroencephalography revealed a significant decrease in the delta-band activity, which originated in the right prefrontal cortex and correlated with improvements in facial affect recognition.