Excitatory Deep Transcranial Magnetic Stimulation With H-Coil Over the Right Homologous Broca’s Region Improves Naming in Chronic Post-stroke Aphasia

2013 ◽  
Vol 28 (3) ◽  
pp. 291-298 ◽  
Author(s):  
Raffaella Chieffo ◽  
Federico Ferrari ◽  
Petronilla Battista ◽  
Elise Houdayer ◽  
Arturo Nuara ◽  
...  

Background. The role of the right hemisphere in poststroke aphasia recovery is still controversial and the effects of repetitive transcranial magnetic stimulation (rTMS) over the right homologous Broca’s region have been seldom investigated. Objective. This study aimed to compare the effect of excitatory, inhibitory, and sham rTMS delivered with H-coil over the right inferior frontal gyrus in chronic aphasic patients. Methods. Five right-handed poststroke aphasic patients underwent a picture naming task before and immediately after each of 3 sessions of rTMS: excitatory (10 Hz), inhibitory (1 Hz), and sham rTMS, in random sequence and separated by at least 1 week. Results. Only the excitatory 10-Hz stimulation was associated with a significant improvement in naming performance ( P = .043) and was significantly more effective than 1-Hz rTMS ( P = .043). Conclusions. A single session of excitatory deep brain rTMS over the right inferior frontal gyrus with H-coil significantly improves naming in right-handed chronic poststroke aphasic patients. This result is in line with the hypothesis of a positive, rather than detrimental, role of the right hemisphere in chronic aphasia due to a left-hemispheric stroke.

2008 ◽  
Vol 20 (1) ◽  
pp. 170-181 ◽  
Author(s):  
Gorana Pobric ◽  
Nira Mashal ◽  
Miriam Faust ◽  
Michal Lavidor

Previous research suggests that the right hemisphere (RH) may contribute uniquely to the processing of metaphoric language. However, causal relationships between local brain activity in the RH and metaphors comprehension were never established. In addition, most studies have focused on familiar metaphoric expressions which might be processed similarly to any conventional word combination. The present study was designed to overcome these two problems by employing repetitive transcranial magnetic stimulation (rTMS) to examine the role of the RH in processing novel metaphoric expressions taken from poetry. Right-handed participants were presented with four types of word pairs, literal, conventional metaphoric and novel metaphoric expressions, and unrelated word pairs, and were asked to perform a semantic judgment task. rTMS of the right posterior superior temporal sulcus disrupted processing of novel but not conventional metaphors, whereas rTMS over the left inferior frontal gyrus selectively impaired processing of literal word pairs and conventional but not novel metaphors (Experiment 1). In a further experiment, we showed that these effects were due to right-left asymmetries rather than posterior-anterior differences (Experiment 2). This is the first demonstration of TMS-induced impairment in processing novel metaphoric expressions, and as such, confirms the specialization of the RH in the activation of a broader range of related meanings than the left hemisphere, including novel, nonsalient meanings. The findings thus suggest that the RH may be critically involved in at least one important component of novel metaphor comprehension, the integration of the individual meanings of two seemingly unrelated concepts into a meaningful metaphoric expression.


2021 ◽  
Author(s):  
Felix Mueller-Sarnowski ◽  
Nico Sollmann ◽  
Axel Schröder ◽  
Leen Houri ◽  
Sebastian Ille ◽  
...  

Abstract Neuronavigated repetitive transcranial magnetic stimulation (nrTMS) is an innovative technique that provides insight into language function with high accuracy in time and space. So far, nrTMS has mainly been applied in presurgical language mapping of patients with cranial neoplasms. For the present study nrTMS was used for language mapping in primary progressive aphasia Seven patients (median age: 70 years, 4 males) with the non-fluent variant of primary progressive aphasia were included in this pilot study. Inhibitory nrTMS trains (5 Hz, 40 % resting motor threshold) caused virtual lesions at 46 standardized cortical stimulation targets per hemisphere. Patients’ errors in a naming task during stimulation were counted. The majority of errors induced occurred during frontal lobe stimulation (34.3 %). Timing errors and non-responses were most frequent. More errors were induced in the right hemisphere (58%) than in the left hemisphere (42%). Mapping was tolerated by all patients, however, discomfort or pain was reported for stimulation of frontal areas. The elevated right-hemispheric error rate in our study supports the hypothesis of a partial shift of language function to the right hemisphere in neurodegenerative aphasia during the course of disease and therefore points to the existence of significant neuronal plasticity in primary progressive aphasia. While this is an interesting finding for neurodegenerative disorders per se, its promotion might also harbor future therapeutic targets.


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.


2012 ◽  
Vol 108 (2) ◽  
pp. 380-389 ◽  
Author(s):  
Weidong Cai ◽  
Jobi S. George ◽  
Frederick Verbruggen ◽  
Christopher D. Chambers ◽  
Adam R. Aron

Rapidly stopping action engages a network in the brain including the right presupplementary motor area (preSMA), the right inferior frontal gyrus, and the basal ganglia. Yet the functional role of these different regions within the overall network still remains unclear. Here we focused on the role of the right preSMA in behavioral stopping. We hypothesized that the underlying neurocognitive function of this region is one or more of setting up a stopping rule in advance, modulating response tendencies (e.g., slowing down in anticipation of stopping), and implementing stopping when the stop signal occurs. We performed two experiments with magnetic resonance imaging (MRI)–guided, event-related, transcranial magnetic stimulation(TMS), during the performance of variants of the stop signal task. In experiment 1 we show that stimulation of the right preSMA versus vertex (control site) slowed the implementation of stopping (measured via stop signal reaction time) but had no influence on modulation of response tendencies. In experiment 2, we showed that stimulation of the right preSMA slowed implementation of stopping in a mechanistically selective form of stopping but had no influence on setting up stopping rules. The results go beyond the replication of prior findings by showing that TMS of the right preSMA impairs stopping behavior (including a behaviorally selective form of stopping) through a specific disruption of the implementation of stopping. Future studies are required to establish whether this was due to stimulation of the right preSMA itself or because of remote effects on the wider stopping network.


2002 ◽  
Vol 14 (7) ◽  
pp. 1109-1120 ◽  
Author(s):  
Marie-Hélène Grosbras ◽  
Tomáš Paus

When looking at one object, human subjects can shift their attention to another object in their visual field without moving the eyes. Such shifts of attention activate the same brain regions as those involved in the execution of eye movements. Here we investigate the role of one of the main cortical oculomotor area, namely, the frontal eye field (FEF), in shifts of attention. We used transcranial magnetic stimulation (TMS), a technique known to disrupt transiently eye-movements preparation. We hypothesized that if the FEF is a necessary element in the network involved in shifting attention without moving the eyes, then TMS should also disrupt visuospatial attention. For each volunteer, we positioned the TMS coil over the probabilistic anatomical location of the FEF, and we verified that single pulses delayed eye movements. We then applied TMS during a visuospatial attention task. In this task, a central arrow directed shifts of attention and the subject responded by a keypress to a subsequent visual peripheral target without moving the eyes from the central fixation point. In a few trials, the cue was invalid or uninformative, yielding slower responses than when the cue was valid. We delivered single pulses either 53 msec before or 70 msec after target onset. Contrary to our prediction, the main effect of the stimulation was a decrease in reaction time when it was applied 53 msec before target onset. TMS over the left hemisphere facilitated responses to targets in the right hemifield only and for all cueing conditions, whereas TMS over the right hemisphere had a bilateral effect for valid and neutral but not invalid cueing. Thus, TMS interfered with shift of attention only in the case of right hemisphere stimulation: it increased the cost of invalid cueing. Our results suggest that TMS over the FEF facilitates visual detection, and thereby reduces reaction time. This finding provides new insights into the role of the human FEF in processing visual information. The functional asymmetry observed for both facilitation of visual detection and interference with shifts of attention provides further evidence for the dominance of the right hemisphere for those processes. Our results also underline that the disruptive or facilitative effect of TMS over a given region depends upon the behavioral context.


Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2219
Author(s):  
Nathira Ahmad ◽  
Samantha Zorns ◽  
Katherine Chavarria ◽  
Janet Brenya ◽  
Aleksandra Janowska ◽  
...  

In the past decade, the functional role of the TPJ (Temporal Parietal Junction) has become more evident in terms of its contribution to social cognition. Studies have revealed the TPJ as a ‘distinguisher’ of self and other with research focused on non-clinical populations as well as in individuals with Autism and Type I Schizophrenia. Further research has focused on the integration of self-other distinctions with proprioception. Much of what we now know about the causal role of the right TPJ derives from TMS (Transcranial Magnetic Stimulation), rTMS repetitive Transcranial Magnetic Stimulation), and tDCS (transcranial Direct Cortical Stimulation). In this review, we focus on the role of the right TPJ as a moderator of self, which is integrated and distinct from ‘other’ and how brain stimulation has established the causal relationship between the underlying cortex and agency.


2013 ◽  
Vol 118 (1) ◽  
pp. 175-179 ◽  
Author(s):  
Nico Sollmann ◽  
Thomas Picht ◽  
Jyrki P. Mäkelä ◽  
Bernhard Meyer ◽  
Florian Ringel ◽  
...  

Up to now, navigated transcranial magnetic stimulation (nTMS) has been used for motor mapping in the vicinity of rolandic brain lesions. Recently, nTMS has also been suggested to be useful in mapping human language areas. The authors describe the case of a left-handed patient with a left-side glioblastoma within the opercular inferior frontal gyrus who presented with severe motor aphasia. Preoperative functional MRI (fMRI) indicated speech dominance of the right hemisphere and did not show any language-related activation in the vicinity of the tumor. Navigated TMS, however, showed a significantly higher rate of induced speech arrests for the left than for the right. Left-side direct cortical stimulation induced clear speech arrests during awake surgery. This case suggests that nTMS may be useful for preoperative speech mapping in tumors affecting the anatomy, vasculature, and brain oxygen levels and therefore impairing fMRI reliability.


2004 ◽  
Vol 16 (5) ◽  
pp. 848-855 ◽  
Author(s):  
Massimiliano Oliveri ◽  
Leonor Romero ◽  
Costanza Papagno

It has been suggested that figurative language, which includes idioms, is controlled by the right hemisphere. We tested the right hemisphere hypothesis by using repetitive transcranial magnetic stimulation (rTMS) to transiently disrupt the function of the frontal and temporal areas of the right versus left hemisphere in a group of normal participants involved in a task of opaque idiom versus literal sentence comprehension. Forty opaque, nonambiguous idioms were selected. Fifteen young healthy participants underwent rTMS in two sessions. The experiment was run in five blocks, corresponding to the four stimulated scalp positions (left frontal and temporal and right frontal and temporal) and a baseline. Each block consisted of 16 trials—8 trials with idioms and 8 trials with literal sentences. In each trial, the subject was presented with a written sentence, which appeared on the screen for 2000 msec, followed by a pair of pictures for 2500 msec, one of which corresponded to the sentence. The alternative corresponded to the literal meaning for idioms and to a sentence differing in a detail in the case of literal sentences. The subject had to press a button corresponding to the picture matching the string. Reaction times increased following left temporal rTMS, whereas they were unaffected by right hemisphere rTMS, with no difference between idiomatic and literal sentences. Left temporal rTMS also reduced accuracy without differences between the two types of sentences. These data suggest that opaque idiom and literal sentence comprehension depends on the left temporal cortex.


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