Search results for "Motor"
showing 10 items of 3137 documents
Visual distraction: a behavioral and event-related brain potential study in humans.
2006
Recent studies reported that the detection of changes in the visual stimulation results in distraction of cognitive processing. From event-related brain potentials it was argued that distraction is triggered by the automatic detection of deviants. We tested whether distraction effects are confined to the detection of a deviation or can be triggered by changes per se, namely by rare stimuli that were not deviant with respect to the stimulation. The results obtained comparable early event-related brain potential effects for rare and deviant stimuli, suggesting an automatic detection of these changes. In contrast, behavioral distraction and attention-related event-related brain potential compo…
Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) during capsaicin-induced pain: modulatory effects o…
2009
Evidence by functional imaging studies suggests the role of left DLPFC in the inhibitory control of nociceptive transmission system. Pain exerts an inhibitory modulation on motor cortex, reducing MEP amplitude, while the effect of pain on motor intracortical excitability has not been studied so far. In the present study, we explored in healthy subjects the effect of capsaicin-induced pain and the modulatory influences of left DLPFC stimulation on motor corticospinal and intracortical excitability. Capsaicin was applied on the dorsal surface of the right hand, and measures of motor corticospinal excitability (test-MEP) and short intracortical inhibition (SICI) and facilitation (ICF) were obt…
Modulation of corticospinal excitability by repetitive transcranial magnetic stimulation
2000
Abstract Objective : Repetitive transcranial magnetic stimulation (rTMS) is able to modulate the corticospinal excitability and the effects appear to last beyond the duration of the rTMS itself. Different studies, employing different rTMS parameters, report different modulation of corticospinal excitability ranging from inhibition to facilitation. Intraindividual variability of these effects and their reproducibility are unclear. Methods : We examined the modulatory effects of rTMS to the motor cortex at various frequencies (1, 10, 20 Hz) and at different time-points in twenty healthy volunteers. Results : We observed significant inhibition of MEPs following 1 Hz rTMS and significant facili…
Facilitatory effects of 1 Hz rTMS in motor cortex of patients affected by migraine with aura
2004
We previously showed paradoxical facilitatory effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on striate and extrastriate cortex of patients suffering migraine with aura. In this study we evaluated the effects of 1 Hz rTMS on the excitability of inhibitory and facilitatory circuits of motor cortex to explore whether the abnormal pattern of excitability extends beyond the sensory cortex also involving motor areas in migraine with aura. Nine patients affected by migraine with aura and eight healthy controls entered into the study. The hot spot for activation of the right abductor pollicis brevis (APB) was checked by means of a figure-of-eight coil and motor thresh…
Contralateral hand anesthesia transiently improves poststroke sensory deficits.
2005
Objective To test a possible strategy to alleviate somatosensory deficits after stroke. Methods Here, we applied ischemic nerve block to the intact hand of patients with chronic stroke, which in healthy subjects elicits improvements in sensibility of the other hand. Results We found that sensibility in the affected hand improved with intact hand anesthesia, but not with intact foot anesthesia or no anesthesia. Interpretation We conclude that reduction of sensory input from the intact hand leads to site-specific improvements in tactile discriminative skills in the affected hand after the period of anesthesia, a potentially relevant finding in designing neurorehabilitative interventions. Ann …
Comparison of three methods for evaluation of work postures in a truck assembly plant
2017
International audience; This study compared the results of three risk assessment tools (self-reported questionnaire, observational tool, direct measurement method) for the upper limbs and back in a truck assembly plant at two cycle times (11 and 8 min). The weighted Kappa factor showed fair agreement between the observational and direct measurement method for the arm (0.39) and back (0.47). The weighted Kappa factor for these methods was poor for the neck (0) and wrist (0) but the observed proportional agreement (P-o) was 0.78 for the neck and 0.83 for the wrist. The weighted Kappa factor between questionnaire and direct measurement showed poor or slight agreement (0) for different body seg…
Urological dysfunctions in patients with Parkinson’s disease: clues from clinical and non-invasive urological assessment
2018
Abstract Background Autonomic nervous system dysfunction, common in patients with Parkinson’s disease (PD), causes significant morbidity and it is correlated with poor quality of life. To assess frequency of urinary symptoms in patients with PD, without conditions known to interfere with urinary function. Methods Non-demented PD patients were consecutively enrolled from the outpatients clinic of our department. Scales investigating motor and non-motor symptoms were carried out. Evaluation of urinary dysfunctions was carried out using the AUTonomic Scale for Outcomes in Parkinson’s disease (SCOPA-AUT) questionnaire. Patients underwent noninvasive urological studies (nUS), including uroflowme…
Induction of vascular endothelial growth factor release by transcutaneous frequency modulated neural stimulation in diabetic polyneuropathy
2008
Background: Pharmacological treatment for diabetic polyneuropathy (DP) has shown limited benefit; frequency-modulated electrical stimulation (FREMS) has shown positive results in pain control and nerve conduction velocity in DP. Objective: To investigate the effects of FREMS vs transcutaneous electrical nerve stimulation (TENS) on the release of vascular endothelial growth factor (VEGF) in Type 2 diabetic and in non-diabetic subjects. Methods: 10 non-diabetic [mean age 37±5 yr; females (F)/males (M): 6/4] and 10 Type 2 diabetic subjects (mean age 52±6 yr; F/M: 5/5) with DP underwent TENS (for 10 min) followed by 30 min interval without electrical stimulation, and then FREMS (for 10 min) ove…
Neural Architecture of Selective Stopping Strategies: Distinct Brain Activity Patterns Are Associated with Attentional Capture But Not with Outright …
2017
In stimulus-selective stop-signal tasks, the salient stop signal needs attentional processing before genuine response inhibition is completed. Differential prefrontal involvement in attentional capture and response inhibition has been linked to the right inferior frontal junction (IFJ) and ventrolateral prefrontal cortex (VLPFC), respectively. Recently, it has been suggested that stimulus-selective stopping may be accomplished by the following different strategies: individuals may selectively inhibit their response only upon detecting a stop signal (independent discriminate then stop strategy) or unselectively whenever detecting a stop or attentional capture signal (stop then discriminate s…
Altered effective connectivity during working memory performance in schizophrenia: a study with fMRI and structural equation modeling
2003
The present study aimed to explore altered effective connectivity in schizophrenic patients while performing a 2-back working memory task. Twelve right-handed, schizophrenic patients treated with typical or atypical antipsychotics and 6 healthy control subjects were studied with fMRI while performing a "2-back" working memory task. Effective connectivity within a cortical-subcortical-cerebellar network for mnemonic information processing was assessed and compared between both groups. The path model included cortico-cortical connections comprising the parietal association cortex, ventrolateral prefrontal cortex (VLPFC), and the dorsolateral prefrontal cortex (DLPFC) as well as a cortico-cere…