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Hz rTMS (hz + rtm)
Selected AbstractsOne-year follow up of patients with chronic tinnitus treated with left temporoparietal rTMSEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2009E. M. Khedr Background and purpose: Although there are a number of positive reports on the therapeutic effects of repetitive transcranial magnetic stimulation (rTMS) for treatment of tinnitus, there are few details about the duration of treatment effects or the relative efficiency of different rTMS protocols. Methods: Sixty six patients with chronic tinnitus were divided into four groups, receiving sham rTMS, 1, 10 and 25 Hz rTMS applied each day for 10 days over left temporoparietal cortex. They were followed up at 4 months and 1 year using the tinnitus questionnaire [Tinnitus Handicap Inventory(THI)] and self ratings of annoyance as well as measures of residual inhibition. Results: A two factor anova revealed a significant ,rTMS' × ,time' interaction indicating that real and sham rTMS had different effects on the THI scale and annoyance of tinnitus (P = 0.026 and 0.046 respectively). After 1 year, the tinnitus was absent in one or both ears of 10 patients who had received real rTMS: one of these was in the 1 Hz group, four patients were in the 10 Hz group and five patients were in the 25 Hz group. Conclusion: Some patients show a lasting benefit at 1 year after 10 days of rTMS treatment. It appears that treatment at 10 or 25 Hz may be more beneficial than at 1 Hz, although more work is necessary to validate this conclusion. [source] Beneficial effect of transcranial magnetic stimulation on sleep in Parkinson's disease,MOVEMENT DISORDERS, Issue 6 2009Karin D. van Dijk MD Abstract Sleep disorders are common in Parkinson's disease (PD) and have profound negative influences on quality of life. Sleep structure in healthy participants can be changed by repetitive transcranial magnetic stimulation (rTMS), but this has never been studied systematically in PD. Therefore, we characterized sleep in PD patients and examined effects of rTMS using a combination of actigraphy and a pressure sensitive pad. Thirteen PD patients received 5 Hz rTMS over the motor or parietal cortex. Actigraphic sleep estimates were obtained before, during and after rTMS, as well as compared with 8 healthy, age-matched controls. Motor symptoms and mood were evaluated before and after rTMS. Mixed-model regression analyses indicated that PD patients slept shorter (350 ± 17 vs. 419 ± 24 min., P = 0.02), more fragmented (fragmentation index 41 ± 4 vs. 22 ± 2, P = 0.0004) and had a lower sleep efficiency (77 ± 2 vs. 86 ± 2%, P = 0.002) and longer nocturnal awakenings (3.4 ± 0.2 vs. 2.3 ± 0.2 min., P = 0.003) than healthy controls. rTMS over the parietal, but not over the motor cortex improved sleep fragmentation (P = 0.0002) and sleep efficiency (P = 0.0002) and reduced the average duration of nocturnal awakenings (P = 0.02). No change of motor symptoms or mood was observed. Disturbed sleep in PD patients may partly be reversed by parietal rTMS, without affecting motor symptoms or mood. © 2009 Movement Disorder Society [source] Abnormal plasticity of the sensorimotor cortex to slow repetitive transcranial magnetic stimulation in patients with writer's crampMOVEMENT DISORDERS, Issue 1 2007Tobias Bäumer MD Abstract Previous studies demonstrated functional abnormalities in the somatosensory system, including a distorted functional organization of the somatosensory cortex (S1) in patients with writer's cramp. We tested the hypothesis that these functional alterations render S1 of these patients more susceptible to the "inhibitory" effects of subthreshold 1 Hz repetitive transcranial magnetic stimulation (rTMS) given to S1. Seven patients with writer's cramp and eight healthy subjects were studied. Patients also received rTMS to the motor cortex hand area (M1). As an outcome measure, short-latency afferent inhibition (SAI) was tested. SAI was studied in the relaxed first dorsal interosseous muscle using conditioning electrical stimulation of the index finger and TMS pulses over the contralateral M1. Baseline SAI did not differ between groups. S1 but not M1 rTMS reduced SAI in patients. rTMS had no effects on SAI in healthy subjects. Because SAI is mediated predominantly at a cortical level in the sensorimotor cortex, we conclude that there is an abnormal responsiveness of this area to 1 Hz rTMS in writer's cramp, which may represent a trait toward maladaptive plasticity in the sensorimotor system in these patients. © 2006 Movement Disorder Society [source] Low-frequency repetitive transcranial magnetic stimulation suppresses specific excitatory circuits in the human motor cortexTHE JOURNAL OF PHYSIOLOGY, Issue 18 2008V. Di Lazzaro Previous studies have shown that low-frequency repetitive transcranial magnetic stimulation (rTMS) suppresses motor-evoked potentials (MEPs) evoked by single pulse TMS. The aim of the present paper was to investigate the central nervous system level at which rTMS produces a suppression of MEP amplitude. We recorded corticospinal volleys evoked by single pulse TMS of the motor cortex before and after 1 Hz rTMS in five conscious subjects who had an electrode implanted in the cervical epidural space for the control of pain. One of the patients had Parkinson's disease and was studied on medication. Repetitive TMS significantly suppressed the amplitude of later I-waves, and reduced the amplitude of concomitantly recorded MEPs. The earliest I-wave was not significantly modified by rTMS. The present results show that 1 Hz rTMS may decrease the amplitude of later descending waves, consistent with a cortical origin of the effect of 1 Hz rTMS on MEPs. [source] Unilateral suppression of pharyngeal motor cortex to repetitive transcranial magnetic stimulation reveals functional asymmetry in the hemispheric projections to human swallowingTHE JOURNAL OF PHYSIOLOGY, Issue 2 2007Satish Mistry Inhibitory patterns of repetitive transcranial magnetic stimulation (rTMS) were applied to pharyngeal motor cortex in order to establish its role in modulating swallowing activity and provide evidence for functionally relevant hemispheric asymmetry. Healthy volunteers underwent single pulse TMS before and for 60 min after differing intensities of 1 Hz rTMS (n= 9, 6 male, 3 female, mean age 34 ± 3 years) or theta burst stimulation (TBS) (n= 9, 6 male, 3 female, mean age 37 ± 4 years). Electromyographic responses recorded from pharynx and hand were used as a measure of cortico-motor pathway excitability. Swallowing behaviour was then examined with a reaction time protocol, before and for up to 60 min after the most effective inhibitory protocol (1 Hz) applied to each hemisphere. Interventions were conducted on separate days and compared to sham using ANOVA. Only high intensity 1 Hz rTMS consistently suppressed pharyngeal motor cortex immediately and for up to 45 min (,34 ± 7%, P, 0.001). Adjacent hand and contralateral pharyngeal motor cortex showed no change in response (,15 ± 12%, P= 0.14 and 15 ± 12%, P= 0.45, respectively). When used to unilaterally disrupt each hemisphere, rTMS to pharyngeal motor cortex with the stronger responses altered normal (,12 ± 3%, P, 0.001) and fast (,9 ± 4%, P, 0.009) swallow times, not seen following rTMS to the contralateral cortex or after sham. Thus, suppression of pharyngeal motor cortex to rTMS is intensity and frequency dependent, which when applied to each hemisphere reveals functionally relevant asymmetry in the motor control of human swallowing. [source] Modulatory effects of low- and high-frequency repetitive transcranial magnetic stimulation on visual cortex of healthy subjects undergoing light deprivationTHE JOURNAL OF PHYSIOLOGY, Issue 2 2005Brigida Fierro The aim of the present study was to explore further the effects of light deprivation (LD) on visual cortex excitability. Healthy subjects reporting reliable induction of phosphenes by occipital transcranial magnetic stimulation (TMS) underwent 60 min of complete LD. Phosphene threshold (PT) was measured before (T0), after 45 min (T1) and 60 min (T2) of LD, and then every 10 min after light re-exposure until recovery to T0 values. Repetitive TMS (rTMS) (at 1 or 10 Hz) was applied in separate sessions during the last 15 min of LD. PTs significantly decreased after 45 min of LD. rTMS differentially modified the effects of 60 min LD on PTs depending on stimulation frequency. One hertz rTMS did not change the decreasing of PT values as observed in baseline condition, but significantly prolonged the time to recover T0 PT values after light re-exposure. By contrast, 10 Hz rTMS significantly increased PT and the time to recover T0 PT values after light re-exposure was shortened. The results of this study show that the modulatory effects of different rTMS frequencies on visual cortex critically depend on the pre-existing excitability state of inhibitory and facilitatory circuits, and provide novel insights into the neurophysiological changes that take place in the visual cortex following functional visual deafferentation. [source] | ||||||||||