高低频重复经颅磁刺激治疗卒中后上肢痉挛的对照研究

目的 探讨高、低频重复经颅磁刺激（repetitive transcranial magnetic stimulation,rTMS）大脑初级运动皮层（M1区）治疗卒中后上肢痉挛的临床疗效及差异。      

重复经颅磁刺激对脑梗死大鼠梗死侧皮质内源性神经干细胞激活、增殖的影响

目的研究重复经颅磁刺激(rTMS)对脑梗死大鼠神经功能恢复及梗死侧皮质内源性神经干细胞激活、增殖的影响。方法将72只雄性SD大鼠随机分为模型组、假刺激组、rTMS组,每组24只,各组根据脑梗死后不同时间点再分为1、7、14、21 d四个亚组,每个亚组6只。采用线栓法制作左侧大脑中动脉闭塞脑梗死模型。rTMS组于动物清醒后当天即给予每天2次、每次30个脉冲的rTMS治疗(频率为0.5 Hz,场强为1.33 T);假刺激组模拟rTMS固定大鼠头部放置线圈但不给予脉冲磁刺激;模型组不给任何治疗。各组在规定的时间点应用改良的神经功能缺损评分(mNSS)进行神经功能评定,治疗结束前24 h腹腔注射5-溴脱氧尿嘧啶核苷(BrdU),应用免疫组织化学技术检测梗死侧皮质巢蛋白(nestin)及BrdU表达阳性细胞的数量。结果 rTMS组脑梗死后7、14、21 d mNSS评分明显低于假刺激组及模型组同时间点大鼠(P<0.05),假刺激组及模型组大鼠脑梗死后不同时间点mNSS评分差异不明显(P>0.05)。脑梗死后1d模型组、假刺激组和rTMS组梗死灶周围皮质均可见nestin及BrdU阳性细胞,7 d达高峰。和假刺激组及模型组同时间点相比,rTMS组7、14、21 d nestin及BrdU阳性细胞数量明显增多,两者比较差异明显(P<0.05)。结论 rTMS能促进脑梗死大鼠神经功能恢复,机制可能与rTMS治疗能促进脑梗死周围内源性神经干细胞的激活及增殖有关。     

Effects of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper limb motor dysfunction in patients with subacute cerebral infarction

Studieshave confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function atfer cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. hTis study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. hTese patients were randomly assigned to three groups. hTe low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex (M1). hTe high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks atfer treatment, cortical latency of motor-evoked potentials and central motor conduction time were signiifcantly lower compared with before treatment. Moreover, motor function scores were signiifcantly improved. hTe above indices for the low- and high-frequency groups were signiifcantly different compared with the sham group. However, there was no signiifcant difference between the low- and high-frequency groups. hTe results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.     

不同频率重复经颅磁刺激对急性脑梗死患者静脉溶栓治疗的影响

目的比较不同频率的重复经颅磁刺激(rTMS)对急性脑梗死患者静脉溶栓治疗的影响。方法 141例急性脑梗死患者随机分为假rTMS治疗组、rTMS 1 Hz组、rTMS 2 Hz组、rTMS 5 Hz组、rTMS 10 Hz组和溶栓对照组,均予以尿激酶溶栓治疗。rTMS 1~10 Hz各组依次分别在溶栓同时给予rTMS 1 Hz、2 Hz、5 Hz、10 Hz治疗,假rTMS治疗组予以假rTMS刺激。所有患者于治疗前及治疗后24 h时进行美国国立卫生研究院卒中量表(NIHSS)评分,观察并记录各组不良反应情况。结果各组治疗后NIHSS评分均较治疗前明显下降(均P<0.05)。治疗后rTMS 1~10 Hz各组NIHSS评分均较溶栓对照组明显下降,其中rTMS 5 Hz组NIHSS评分最低(均P<0.05)。rTMS 1~10 Hz各组有效率(64.0%、76.2%、81.8%、83.3%)均明显高于假rTMS治疗组(42.3%)和溶栓对照组(47.8%)(均P<0.05)。其中,rTMS 2 Hz组、rTMS 5 Hz组与rTMS 10 Hz组有效率均高于rTMS 1 Hz组(均P<0.05)。各组间不良反应的比...     

Lack of adverse cognitive effects of 1 Hz and 20 Hz repetitive transcranial magnetic stimulation at 100% of motor threshold over left prefrontal cortex in depression.

OBJECTIVE: The potential therapeutic effects of repetative transcranial magnetic stimulation (rTMS) are being examined in various neuropsychiatric illnesses. This study assesses the cognitive performance of depressed patients receiving high or low frequency rTMS for 10 days. METHODS: 18 depressed patients participated in a randomized double-blind cross-over study exploring the antidepressant effects of 2 weeks (10 daily) of sham, 1 Hz, or 20 Hz rTMS administered over the left dorsolateral prefrontal cortex at 100% of motor threshold (MT). A subgroup completed a battery of cognitive tests at baseline and following each 2-week phase of treatment, and differences in performance were assessed using paired t -tests and were correlated with the degree of clinical improvement using Hamilton Depression Rating Scale scores. RESULTS: There were no major changes in cognitive test scores as a result of 10 days of either 1 Hz or 20 Hz rTMS. Moreover, any minor attenuations in cognition were not related to the degree of clinical improvement. CONCLUSIONS: Cognitive functioning in many domains following 2 weeks of 1 Hz or 20 Hz rTMS at 100% MT over the left dorsolateral prefrontal cortex in depressed patients is not disrupted.     

Interhemispheric effects of high and low frequency rTMS in healthy humans.

OBJECTIVE: We investigated whether repetitive transcranial magnetic stimulation (rTMS) applied to the right motor cortex modified the excitability of the unstimulated left motor cortex. METHODS: Interhemispheric effects of 0.5 and 5 Hz subthreshold rTMS over the right motor cortex were examined by single pulse and paired pulse TMS and by transcranial electrical stimulation (TES) applied to the unstimulated left motor cortex. The effects of (a) 1800 pulses real and sham rTMS with 5 Hz, (b) 180 pulses real and sham rTMS with 0.5 Hz and (c) 1800 pulses real rTMS with 0.5 Hz were studied. RESULTS: Following 5 Hz right motor rTMS motor evoked potential (MEP) amplitudes induced by single pulse TMS over the left motor cortex increased significantly. Intracortical inhibition (ICI) and facilitation (ICF) and MEP amplitudes evoked by TES were unchanged. Sham stimulation had no influence on motor cortex excitability. After 180 pulses right motor cortex rTMS with 0.5 Hz a significant decrease of left motor ICF, but no change in single pulse MEP amplitudes was found. A similar trend was observed with 1800 pulses rTMS with 0.5 Hz. CONCLUSIONS: High frequency right motor rTMS can increase left motor cortex excitability whereas low frequency right motor rTMS can decrease it. These effects outlast the rTMS by several minutes. The underlying mechanisms mediating interhemispheric excitability changes are likely to be frequency dependent.     

Treatment of articulatory dysfunction in Parkinson's disease using repetitive transcranial magnetic stimulation

Background and purpose: Neuroimaging has demonstrated that improved speech outcomes in Parkinson’s Disease (PD) subsequent to behavioural treatment approaches are associated with increased activity in the motor and pre‐motor cortex. High‐frequency repetitive transcranial magnetic stimulation (rTMS) is capable of modulating cortical activity and has been reported to have significant benefit to general motor function in PD. It is possible that high‐frequency rTMS may also have beneficial outcomes on speech production in PD. Methods: High‐frequency (5 Hz) rTMS was applied to 10 active stimulation and 10 sham placebo patients for 10 min/day (3000 pulses), for 10 days and speech outcome measures and lingual kinematic parameters recorded at baseline and 1 week, 2 and 12 months post‐stimulation. Results: The findings demonstrated positive treatment‐related changes observed in the active rTMS group when compared to the sham placebo control group at 2 and 12 months post‐stimulation in speech intelligibility, communication efficiency ratio, maximum velocity of tongue movements and distance of tongue movements. Conclusion: The results support the use of high‐frequency rTMS as a therapeutic tool for the treatment of articulatory dysfunction in PD.     

Transcranial magnetic stimulation for pain control. Double-blind study of different frequencies against placebo, and correlation with motor cortex stimulation efficacy.

OBJECTIVE: To assess, using a double-blind procedure, the pain-relieving effects of rTMS against placebo, and their predictive value regarding the efficacy of implanted motor cortex stimulation (MCS). METHODS: Three randomised, double-blinded, 25 min sessions of focal rTMS (1 Hz, 20 Hz and sham) were performed in 12 patients, at 2 weeks intervals. Effects on pain were estimated from daily scores across 5 days before, and 6 days after each session. Analgesic effects were correlated with those of subsequent implanted motor cortex stimulation (MCS). RESULTS: Immediately after the stimulating session, pain scores were similarly decreased by all rTMS modalities. Conversely, during the following week, 1 Hz stimulation provided significantly less analgesia than 20 Hz and placebo, and was pro-algesic in some patients. Placebo and 20 Hz rTMS were effective on different patients, and only 20 Hz rTMS predicted the efficacy of subsequent MCS, with no false positives. CONCLUSIONS: While 1Hz rTMS should not be used with analgesic purposes, high-frequency rTMS may become useful to select candidates for MCS. Placebo effects are powerful and should be controlled for. Immediate results after a single rTMS session are misleading. SIGNIFICANCE: Defining rTMS parameters is a crucial step before proposing rTMS as predictive test of SCM efficacy in clinical practice.     

Neural substrates of low‐frequency repetitive transcranial magnetic stimulation during movement in healthy subjects and acute stroke patients. A PET study

The aim of the study was to investigate, with an rTMS/PET protocol, the after‐effects induced by 1‐Hz repetitive transcranial magnetic stimulation (rTMS) in the regional cerebral blood flow (rCBF) of the primary motor cortex (M1) contralateral to that stimulated during a movement. Eighteen healthy subjects underwent a baseline PET scan followed, in randomized order, by a session of Real/Sham low‐frequency (1 Hz) subthreshold rTMS over the right M1 for 23 min. The site of stimulation was fMRI‐guided. After each rTMS session (real or sham), subjects underwent behavioral hand motor tests and four PET scans. During the first two scans, ten subjects (RH group) moved the right hand ipsilateral to the stimulated site and eight subjects (LH group) moved the left contralateral hand. All remained still during the last two scans (rest). Two stroke patients underwent the same protocol with rTMS applied on contralesional M1. Compared with Sham‐rTMS, Real‐rTMS over the right M1 was followed by a significant increase of rCBF during right hand movement in left S1M1, without any significant change in motor performance. The effect lasted less than 1 h. The same rTMS‐induced S1M1 overactivation was observed in the two stroke patients. Commissural connectivity between right dorsal premotor cortex and left M1 after real‐rTMS was observed with a psychophysiological interaction analysis in healthy subjects. No major changes were found for the left hand. These results give further arguments in favor of a plastic commissural connectivity between M1 both in healthy subjects and in stroke patients, and reinforce the potential for therapeutic benefit of low‐frequency rTMS in stroke rehabilitation. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.     

A Near Infra-Red Study of Blood Oxygenation Changes Resulting From High and Low Frequency Repetitive Transcranial Magnetic Stimulation

High and low frequency repetitive transcranial magnetic stimulation (rTMS) are both used to treat major depressive disorder(MDD). However, the physiological mechanisms underlying the therapeutic benefit and the effect of the stimulation frequency are unclear. Twelve healthy participants received 1Hz, 2Hz, and 5Hz active rTMS. Twenty 5 second trains were delivered at left dorsolateral prefrontal cortex at 110% of resting motor threshold with a 25 second inter-train interval. Blood oxygenation (HbO) was significantly reduced following the 1Hz trains compared to the HbO increases observed in both the 2Hz and 5Hz conditions. There was no significant inter-hemispheric difference in response. These results suggest that short trains of high and low frequency rTMS delivered to prefrontal cortex evoke a differential HbO response and provide additional evidence that high frequency trains result in increased neural activity. The findings may provide further explanation for the improved symptoms observed in MDD patients treated with high frequency rTMS.     

Short-lasting impairment of temperature perception by high frequency rTMS of the sensorimotor cortex.

OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has become a useful tool for investigating and even modulating human brain function. RTMS of the human motor cortex can produce changes in excitability that outlast the period of stimulation. To investigate the persistent effect of high-frequency rTMS of sensorimotor cortex (SM1) on somatosensory function. METHODS: We evaluated the thermal thresholds (cold and warm sensation) in 14 normal subjects before and after a short train of 5Hz rTMS over the SM1 or occipital cortex (OC). RESULTS: Threshold for cold perception was increased immediately after rTMS of the left SM1 and no effects at all were noticed after OC stimulation. There was a slight, not significant, increase of warm threshold immediately after the rTMS of the left SM1 and no effects at all were noticed after OC stimulation. CONCLUSIONS: High frequency rTMS over primary sensorimotor cortex seems to modulate sensory function related to thermal (cold) perception. SIGNIFICANCE: The method may be useful for both the study of normal human physiology of temperature perception and for rTMS based manipulation of brain plasticity in patients with sensory disturbances.     

Effects of DBS,premotor rTMS,and levodopa on motor function and silent period in advanced Parkinson's disease

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a widely used and highly effective treatment for patients with advanced Parkinson's disease (PD). Repetitive TMS (rTMS) applied to motor cortical areas has also been shown to improve symptoms in PD and modulate motor cortical excitability. Here, we compared clinical and neurophysiological effects of STN stimulation with those of 1 Hz rTMS given to the dorsal premotor cortex (PMd) and those following intake of levodopa in a group of PD patients with advanced disease. Ten PD patients were studied on 2 consecutive days before and after surgery. Clinical effects were determined using the UPDRS motor score. Motor thresholds, motor‐evoked potential (MEP) amplitudes during slight voluntary contraction, and the cortical silent periods (SP) were measured using TMS. Before surgery effects of levodopa and 1 Hz PMd rTMS and after surgery those of STN stimulation with or without additional levodopa were determined. Levodopa significantly improved clinical symptoms and increased the SP duration. STN stimulation improved clinical symptoms without changing the SP duration. In contrast, 1 Hz PMd rTMS was not effective clinically but normalized the SP duration. Whereas levodopa had widespread effects at different levels of an abnormally active motor network in PD, STN stimulation and PMd rTMS led to either clinical improvement or SP normalization, i.e., only partially reversed abnormal motor network activity. © 2009 Movement Disorder Society     

Slow frequency repetitive transcranial magnetic stimulation affects reaction times, but not priming effects, in a masked prime task.

OBJECTIVE: Slow frequency repetitive transcranial magnetic stimulation (rTMS) reduces motor cortex excitability, but it is unclear whether this has behavioural consequences in healthy subjects. METHODS: We examined the effects of 1 Hz rTMS (train of 20 min; stimulus intensity 80% of active motor threshold) over left motor or left premotor cortex on performance in a visually cued choice reaction time task, using a 'masked prime' paradigm to assess whether rTMS might affect more automatic motor processes. Twelve healthy volunteers participated. RESULTS: Motor cortex rTMS and, to a lesser extent, premotor cortex rTMS resulted in a slowing of right (stimulated) hand responses, but not of left (unstimulated) hand responses. In a control experiment, rTMS of the left somatosensory cortex did not lead to slower right hand responses. DISCUSSION: We conclude that long trains of low intensity 1 Hz rTMS over the motor or premotor cortex can have subtle behavioural consequences outlasting the stimulation. rTMS did not affect the modulation of reaction times by subliminal primes, suggesting that priming effects triggered by subliminal primes are not generated at the level of motor or pre-motor cortex.     

Effects of low versus high frequencies of repetitive transcranial magnetic stimulation on cognitive function and cortical excitability in Alzheimer’s dementia

The aim of the study was to compare the long-term efficacy of high versus low frequency repetitive transcranial magnetic stimulation (rTMS), applied bilaterally over the dorsolateral prefrontal cortex (DLPFC), on cognitive function and cortical excitability of patients with Alzheimer's disease (AD). Forty-five AD patients were randomly classified into three groups. The first two groups received real rTMS over the DLPFC (20 and 1 Hz, respectively) while the third group received sham stimulation. All patients received one session daily for five consecutive days. In each session, rTMS was applied first over the right DLPFC, immediately followed by rTMS over the left DLPFC. Mini Mental State Examination (MMSE), Instrumental Daily Living Activity (IADL) scale and the Geriatric Depression Scale (GDS) were assessed before, after the last (fifth) session, and then followed up at 1 and 3 months. Neurophysiological evaluations included resting and active motor threshold (rMT and aMT), and the duration of transcallosal inhibition (TI) before and after the end of the treatment sessions. At base line assessment there were no significant differences between groups in any of the rating scales. The high frequency rTMS group improved significantly more than the low frequency and sham groups in all rating scales (MMSE, IADL, and GDS) and at all time points after treatment. Measures of cortical excitability immediately after the last treatment session showed that treatment with 20 Hz rTMS reduced TI duration. These results confirm that five daily sessions of high frequency rTMS over the left and then the right DLPFC improves cognitive function in patients with mild to moderate degree of AD. This improvement was maintained for 3 months. High frequency rTMS may be a useful addition to therapy for the treatment of AD.     

Repetitive transcranial magnetic stimulation for levodopa‐induced dyskinesias in Parkinson's disease

In a placebo‐controlled, single‐blinded, crossover study, we assessed the effect of “real” repetitive transcranial magnetic stimulation (rTMS) versus “sham” rTMS (placebo) on peak dose dyskinesias in patients with Parkinson's disease (PD). Ten patients with PD and prominent dyskinesias had rTMS (1,800 pulses; 1 Hz rate) delivered over the motor cortex for 4 consecutive days twice, once real stimuli and once sham stimulation were used; evaluations were done at the baseline and 1 day after the end of each of the treatment series. Direct comparison between sham and real rTMS effects showed no significant difference in clinician‐assessed dyskinesia severity. However, comparison with the baseline showed small but significant reduction in dyskinesia severity following real rTMS but not placebo. The major effect was on dystonia subscore. Similarly, in patient diaries, although both treatments caused reduction in subjective dyskinesia scores during the days of intervention, the effect was sustained for 3 days after the intervention for the real rTMS only. Following rTMS, no side effects and no adverse effects on motor function and PD symptoms were noted. The results suggest the existence of residual beneficial clinical aftereffects of consecutive daily applications of low‐frequency rTMS on dyskinesias in PD. The effects may be further exploited for potential therapeutic uses. © 2008 Movement Disorder Society     

Interventional neurophysiology for pain control: duration of pain relief following repetitive transcranial magnetic stimulation of the motor cortex.

The chronic electrical stimulation of a motor cortical area corresponding to a painful region of the body, by means of surgically-implanted epidural electrodes is a validated therapeutical strategy to control medication-resistant neurogenic pain. Repetitive transcranial magnetic stimulation (rTMS) permits to stimulate non-invasively and precisely the motor cortex. We applied a 20-min session of rTMS of the motor cortex at 10 Hz using a 'real' or a 'sham' coil in a series of 14 patients with intractable pain due to thalamic stroke or trigeminal neuropathy. We studied the effects of rTMS on pain level assessed on a 0-10 visual analogue scale from day 1 to day 12 following the rTMS session. A significant pain decrease was observed up to 8 days after the 'real' rTMS session. This study shows that a transient pain relief can be induced in patients suffering from chronic neurogenic pain during about the week that follows a 20-min session of 10 Hz-rTMS applied over the motor cortex.     

Decreased sensory cortical excitability after 1 Hz rTMS over the ipsilateral primary motor cortex.

OBJECTIVES: To study changes in the excitability of the sensory cortex by repetitive transcranial magnetic stimulation (rTMS) in humans. METHODS: Somatosensory evoked potentials (SEPs) and antidromic sensory nerve action potentials (SNAPs) were elicited by right median nerve stimulation at the wrist before and after low frequency (1 Hz) rTMS over the left motor cortex, lateral premotor cortex, sensory cortex, and also after sham stimulation. The intensity of rTMS was fixed at 1.1 times the active motor threshold at the hand area of motor cortex. RESULTS: N20 peak (N20p)-P25 and P25-N33 amplitudes were suppressed after rTMS over the motor cortex, whereas the N20 onset (N20o)-N20p and SNAP amplitudes were not affected. They recovered to the baseline about 100 min after the rTMS. rTMS over the premotor cortex or sensory cortex or sham stimulation had no suppressive effect on SEPs. CONCLUSIONS: The reduction of N20p-P25 and P25-N33 components without any changes of N20o-N20p amplitude suggests that the suppression occurs in the sensory cortex. rTMS (1 Hz) of the motor cortex induces a long-lasting suppression of the ipsilateral sensory cortex even at an intensity as low as 1.1 times the active motor threshold, probably via cortico-cortical pathways between motor and sensory cortex.     

Opposite effects of high and low frequency rTMS on regional brain activity in depressed patients.

BACKGROUND: High (10-20 Hz) and low frequency (1-5 Hz) repetitive transcranial magnetic stimulation (rTMS) have been explored for possible therapeutic effects in the treatment of neuropsychiatric disorders. As part of a double-blind, placebo-controlled, crossover study evaluating the antidepressant effect of daily rTMS over the left prefrontal cortex, we evaluated changes in absolute regional cerebral blood flow (rCBF) after treatment with 1- and 20-Hz rTMS. Based on preclinical data, we postulated that high frequency rTMS would increase and low frequency rTMS would decrease flow in frontal and related subcortical circuits. METHODS: Ten medication-free, adult patients with major depression (eight unipolar and two bipolar) were serially imaged using (15)O water and positron emission tomography to measure rCBF. Each patient was scanned at baseline and 72 hours after 10 daily treatments with 20-Hz rTMS and 10 daily treatments with 1 Hz rTMS given in a randomized order. TMS was administered over the left prefrontal cortex at 100% of motor threshold (MT). Significant changes in rCBF from pretreatment baseline were determined by paired t test. RESULTS: Twenty-hertz rTMS over the left prefrontal cortex was associated only with increases in rCBF. Significant increases in rCBF across the group of all 10 patients were located in the prefrontal cortex (L > R), the cingulate gyrus (L > R), and the left amygdala, as well as bilateral insula, basal ganglia, uncus, hippocampus, parahippocampus, thalamus, and cerebellum. In contrast, 1-Hz rTMS was associated only with decreases in rCBF. Significant decreases in flow were noted in small areas of the right prefrontal cortex, left medial temporal cortex, left basal ganglia, and left amygdala. The changes in mood following the two rTMS frequencies were inversely related (r = -.78, p <.005, n = 10) such that individuals who improved with one frequency worsened with the other. CONCLUSIONS: These data indicate that 2 weeks of daily 20-Hz rTMS over the left prefrontal cortex at 100% MT induce persistent increases in rCBF in bilateral frontal, limbic, and paralimbic regions implicated in depression, whereas 1-Hz rTMS produces more circumscribed decreases (including in the left amygdala). These data demonstrate frequency-dependent, opposite effects of high and low frequency rTMS on local and distant regional brain activity that may have important implications for clinical therapeutics in various neuropsychiatric disorders.     

Repetitive transcranial magnetic stimulation for the treatment of chronic pain - a pilot study

Invasive electrical stimulation of the motor cortex has been reported to be of therapeutic value in pain control. We were interested whether noninvasive repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex might also act beneficially. Twelve patients with therapy-resistant chronic pain syndromes (mean age 51.3 +/- 12.6, 6 males) were included in a pilot study. They were treated with rTMS of the corresponding motor cortex area for 20 min (20 Hz, 20 x 2 s trains, intensity 80% of motor threshold) and sham stimulation (sequence-controlled cross-over design). Some of the patients (6/6) had an analgesic effect, but for the whole group, the difference between active and sham stimulation did not reach a level of significance (active rTMS: mean VAS reduction -4.0 +/- 15.6%; sham rTMS: -2.3 +/- 8.8%). Further studies using different rTMS stimulation parameters (duration and frequency of rTMS) or stimulation sites (e.g. anterior cingulate gyrus) are strongly encouraged.     

Effect of daily repetitive transcranial magnetic stimulation on motor performance in Parkinson's disease.

Previous studies in patients with Parkinson's disease have reported that a single session of repetitive transcranial magnetic stimulation (rTMS) can improve some or all of the motor symptoms for 30 to 60 minutes. A recent study suggested that repeated sessions of rTMS lead to effects that can last for at least 1 month. Here we report data that both confirm and extend this work. Fifty-five unmedicated PD patients were classified into four groups: two groups (early and late PD) received 25 Hz rTMS bilaterally on the motor arm and leg areas; other groups acted as control for frequency (10 Hz) and for site of stimulation (occipital stimulation). All patients received six consecutive daily sessions (3,000 pulses for each session). The first two groups then received a further three booster sessions (3 consecutive days of rTMS) after 1, 2, and 3 months, while the third group had only one additional session after the first month. Unified Parkinson's Disease Rating Scale (UPDRS), walking time, key-tapping speed, and self-assessment scale were measured for each patient before and after each rTMS session and before and after the monthly sessions. Compared to occipital stimulation, 25 Hz rTMS over motor areas improved all measures in both early and late groups; the group that received 10 Hz rTMS improved more than the occipital group but less than the 25 Hz groups. The effect built up gradually during the sessions and was maintained for 1 month after, with a slight reduction in efficacy. Interestingly, the effect was restored and maintained for the next month by the booster sessions. We conclude that 25 Hz rTMS can lead to cumulative and long-lasting effects on motor performance.