Alteration of Duration Mismatch Negativity Induced by Transcranial Magnetic Stimulation Over the Left Parietal Lobe

2016 ◽  
Vol 48 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Hirokazu Oshima ◽  
Tetsuya Shiga ◽  
Shin-ichi Niwa ◽  
Hiroyuki Enomoto ◽  
Yoshikazu Ugawa ◽  
...  

Mismatch negativity (MMN) is generated by a comparison between an incoming sound and the memory trace of preceding sounds stored in sensory memory without any attention to the sound. N100 (N1) is associated with the afferent response to sound onset and reflects early analysis of stimulus characteristics. MMN generators are present in the temporal and frontal lobe, and N1 generators are present in the temporal lobe. The parietal lobe is involved in MMN generation elicited by a change in duration. The anatomical network connecting these areas, lateralization, and the effect of the side of ear stimulation on MMN remain unknown. Thus, we studied the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) over the left parietal lobe on MMN and N1 in 10 healthy subjects. Low-frequency rTMS over the left parietal lobe decreased the amplitude of MMN following right ear sound stimulation, but the amplitude was unaffected with left ear sound stimulation. We observed no significant changes in the amplitude of N1 or the latency of MMN or N1. These results suggest that low-frequency rTMS over the left parietal lobe modulates the detection of early auditory changes in duration in healthy subjects. Stimulation that is contralateral to the side of the ear experiencing sound may affect the generation of duration MMN more than ipsilateral stimulation.

2016 ◽  
Vol 38 ◽  
pp. 40-44 ◽  
Author(s):  
E. Poulet ◽  
F. Galvao ◽  
E. Haffen ◽  
D. Szekely ◽  
C. Brault ◽  
...  

AbstractBackgroundDespite growing evidence supporting the clinical interest of repetitive transcranial magnetic stimulation (rTMS) in treatment-resistant depression (TRD), little is known regarding the effects of clinical and sociodemographic factors on the clinical outcome in patients.MethodsWe retrospectively investigated the effects of clinical (using the 3-factor model of the Montgomery-Åsberg depression rating scale [MADRS] encompassing dysphoria, retardation and vegetative symptoms) and sociodemographic characteristics of participants on clinical outcome in a sample of 54 TRD patients receiving low frequency rTMS (1 Hz, 360 pulses) applied over the right dorsolateral prefrontal cortex combined with sham venlafaxine.ResultsResponders (n= 29) displayed lower retardation baseline scores (13.6 ± 2.9) than non-responders (15.6 ± 2.9;n= 25;P= 0.02). We also observed a significant difference between the numbers of ex-smokers in responders and non-responders groups; all ex-smokers (n= 8) were responders to rTMS (P= 0.005).ConclusionLow MADRS retardation factor and ex-smoker status is highly prevalent in responders to low frequency rTMS. Further studies are needed to investigate the predictive value of these factors.


2019 ◽  
Vol 11 (2) ◽  
pp. 189-198 ◽  
Author(s):  
Mimpei Kawamura ◽  
Nobuhiro Takahashi ◽  
Yasutaka Kobayashi

Several reports on repetitive transcranial magnetic stimulation (rTMS) for the treatment of aphasia caused by damage to the left inferior frontal gyrus state that low-frequency rTMS therapy for the right inferior frontal gyrus, which is contralateral to the focus area, is effective for improving verbal expression. However, most of these reports have studied the effects of rTMS therapy for comparatively mild aphasia. This study attempted to perform low-frequency rTMS on the right posterior superior temporal gyrus (BA22), which is the center for language reception for aphasia patients with a drastic decline in verbal expression due to damage to the left inferior frontal gyrus and a considerable decline in language perception. The participants performed a language task that was displayed on a computer monitor during rTMS. In addition, intensive speech-language and hearing therapy was performed by the therapist after rTMS. This study reports that a resultant improvement in language perception was observed in the activated brain regions based on neuropsychological tests and functional magnetic resonance imaging. This study is considered to be significant as it highlights a new method of rTMS treatment for severe aphasia.


2009 ◽  
Vol 43 (4) ◽  
pp. 386-392 ◽  
Author(s):  
Dhruv Bagati ◽  
Shamshul Haque Nizamie ◽  
Ravi Prakash

Objective: Auditory hallucinations are a characteristic symptom of schizophrenia and are usually resistant to treatment. The present study was conducted to further support the findings that repetitive transcranial magnetic stimulation (rTMS) reduces auditory hallucinations, and to evaluate the effect of low-frequency rTMS on auditory hallucinations in schizophrenia. Methods: Forty schizophrenia patients were included in the study. Patients were randomized to control or experimental group. Low-frequency rTMS (1 Hz, 90% motor threshold) was applied to the left temporoparietal cortex of patients in the experimental group for 10 days following the standard guidelines as an addition to antipsychotic treatment. The control group received only antipsychotics. The changes in the psychopathology scores for the auditory hallucinations were recorded using auditory hallucination recording scale. The rater was blind to the intervention procedure. Results: A significant improvement was found in auditory hallucinations in the experimental group as compared to the control group. Conclusion: Left temporoparietal rTMS warrants further study as an intervention for auditory hallucinations. Data suggest that this intervention selectively alters neurobiological factors determining frequency of these hallucinations.


2015 ◽  
Vol 27 (2) ◽  
pp. 82-89 ◽  
Author(s):  
HongCan Zhu ◽  
ZhaoMing Lu ◽  
YiTing Jin ◽  
XiaoJia Duan ◽  
JunFang Teng ◽  
...  

ObjectivesPrevious studies have demonstrated inconsistent findings regarding the efficacy of low-frequency repetitive transcranial magnetic stimulation (rTMS) in treating motor symptoms of Parkinson’s disease (PD). Therefore, this meta-analysis was conducted to assess the efficacy of low-frequency rTMS.MethodsA comprehensive literature search (including PubMed, CCTR, Embase, Web of Science, CNKI, CBM-disc, NTIS,EAGLE, Clinical Trials, Current Controlled Trials, International Clinical Trials Registry) was conducted dating until June 2014. The key search terms (‘Parkinson’, ‘PD’, ‘transcranial magnetic stimulation’, ‘TMS’, ‘RTMS’ and ‘noninvasive brain stimulation’) produced eight high-quality randomised controlled trials (RCT) of low-frequency rTMS versus sham stimulation.ResultsThese eight studies, composed of 319 patients, were meta-analysed through assessment of the decreased Unified Parkinson’s Disease Rating Scale (UPDRS part III) score. Pooling of the results from these RCTs yielded an effect size of −0.40 (95%CI=−0.73 to −0.06,p<0.05) in UPDRS part III, which indicated that low-frequency rTMS could have 5.05 (95%CI=−1.73 to −8.37) point decrease in UPDRS part III score than sham stimulation.DiscussionLow-frequency rTMS had a significant effect on motor signs in PD. As the number of RCTs and PD patients included here was limited, further large-scale multi-center RCTs were required to validate our conclusions.


Author(s):  
Yupeng Du ◽  
Li Wei ◽  
Huangwei Jiang

Abstract Objective To study the improvements and mechanism of repetitive transcranial magnetic stimulation (rTMS) on swallowing disorders after cerebral infarction. Methods A total of 60 patients with swallowing disorders were randomly assigned to receive high/low-frequency rTMS treatment, another 30 patients without rTMS treatment were included in the control group. The Kubota’s water-swallowing test, video fluoroscopic swallowing study (VFSS), and major intracranial neurotransmitters were analyzed before and after treatment. Results No significant difference was observed in the Kubota’s water-swallowing test scores, the VFSS scores, or the levels of intracranial neurotransmitters between the three groups before treatment. The Kubota’s water-swallowing test scores were significantly reduced after high-frequency rTMS treatment than in the control group; the aspiration degree was significantly increased after high-frequency rTMS treatment than in the control group; the levels of glutamate and dopamine were significantly increased after high-frequency rTMS treatment than in the control group; Moreover, the Kubota’s water-swallowing test scores were significantly reduced after high-frequency rTMS treatment than after low-frequency rTMS treatment; the levels of glutamate and dopamine were significantly increased after high-frequency rTMS treatment than after low-frequency rTMS treatment. Conclusions High-frequency rTMS was effective for swallowing disorders, which may be related to increased levels of intracranial glutamate and dopamine.


2011 ◽  
Vol 106 (4) ◽  
pp. 1614-1621 ◽  
Author(s):  
Cathrin M. Buetefisch ◽  
Benjamin Hines ◽  
Linda Shuster ◽  
Paola Pergami ◽  
Adam Mathes

The role of primary motor cortex (M1) in the control of voluntary movements is still unclear. In brain functional imaging studies of unilateral hand performance, bilateral M1 activation is inconsistently observed, and disruptions of M1 using repetitive transcranial magnetic stimulation (rTMS) lead to variable results in the hand motor performance. As the motor tasks differed qualitatively in these studies, it is conceivable that M1 contribution differs depending on the level of skillfulness. The objective of the present study was to determine whether M1 contribution to hand motor performance differed depending on the level of precision of the motor task. Here, we used low-frequency rTMS of left M1 to determine its effect on the performance of a pointing task that allows the parametric increase of the level of precision and thereby increase the level of required precision quantitatively. We found that low-frequency rTMS improved performance in both hands for the task with the highest demand on precision, whereas performance remained unchanged for the tasks with lower demands. These results suggest that the functional relevance of M1 activity for motor performance changes as a function of motor demand. The bilateral effect of rTMS to left M1 would also support the notion of M1 functions at a higher level in motor control by integrating afferent input from nonprimary motor areas.


2005 ◽  
Vol 94 (3) ◽  
pp. 1668-1675 ◽  
Author(s):  
Pramod Kr. Pal ◽  
Ritsuko Hanajima ◽  
Carolyn A. Gunraj ◽  
Jie-Yuan Li ◽  
Aparna Wagle-Shukla ◽  
...  

We studied the effects of 1-Hz repetitive transcranial magnetic stimulation (rTMS) on the excitability of interhemispheric connections in 13 right-handed healthy volunteers. TMS was performed using figure-eight coils, and surface electromyography (EMG) was recorded from both first dorsal interosseous (FDI) muscles. A paired-pulse method with a conditioning stimulus (CS) to the motor cortex (M1) followed by a test stimulus to the opposite M1 was used to study the interhemispheric inhibition (ppIHI). Both CS and TS were adjusted to produce motor-evoked potentials of ∼1 mV in the contralateral FDI muscles. After baseline measurement of right-to-left IHI (pre-RIHI) and left-to-right IHI (pre-LIHI), rTMS was applied over left M1 at 1 Hz with 900 stimuli at 115% of resting motor threshold. After rTMS, ppIHI was studied using both the pre-rTMS CS (post-RIHI and post-LIHI) and an adjusted post-rTMS CS set to produce 1-mV motor evoked potentials (MEPs; post-RIHIadj and post-LIHIadj). The TS was set to produce 1-mV MEPs. There was a significant reduction in post-LIHI ( P = 0.0049) and post-LIHIadj ( P = 0.0169) compared with pre-LIHI at both interstimulus intervals of 10 and 40 ms. Post-RIHI was significantly reduced compared with pre-RIHI ( P = 0.0015) but pre-RIHI and post-RIHIadj were not significantly different. We conclude that 1-Hz rTMS reduces IHI in both directions but is predominantly from the stimulated to the unstimulated hemisphere. Low-frequency rTMS may be used to modulate the excitability of IHI circuits. Treatment protocols using low-frequency rTMS to reduce cortical excitability in neurological and psychiatric conditions need to take into account their effects on IHI.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Hui Wang ◽  
Bei Li ◽  
Meiye Wang ◽  
Ming Li ◽  
Dongzhen Yu ◽  
...  

Objectives. We investigated factors that contribute to suppression of tinnitus after repetitive transcranial magnetic stimulation (rTMS).Methods. A total of 289 patients with tinnitus underwent active 1 Hz rTMS in the left temporoparietal region. A visual analog scale (VAS) was used to assess tinnitus loudness. All participants were interviewed regarding age, gender, tinnitus duration, laterality and pitch, audiometric parameters, sleep, and so forth. The resting motor thresholds (RMTs) were measured in all patients and 30 age- and gender-matched volunteers.Results. With respect to different factors that contribute to tinnitus suppression, we found improvement in the following domains: shorter duration, normal hearing (OR: 3.25, 95%CI: 2.01–5.27,p=0.001), and without sleep disturbance (OR: 2.51, 95%CI: 1.56–4.1,p=0.005) adjusted for age and gender. The patients with tinnitus lasting less than 1 year were more likely to show suppression of tinnitus (OR: 2.77, 95%CI: 1.48–5.19,p=0.002) compared to those with tinnitus lasting more than 5 years. Tinnitus patients had significantly lower RMTs compared with healthy volunteers.Conclusion. Active low-frequency rTMS results in a significant reduction in the loudness of tinnitus. Significant tinnitus suppression was shown in subjects with shorter tinnitus duration, with normal hearing, and without sleep disturbance.


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