Theta Burst Transcranial Magnetic Stimulation Research Articles

Theta-burst transcranial magnetic stimulation attenuates chronic ischemic demyelination and vascular cognitive impairment in mice

Vascular cognitive impairment and dementia (VCID) is mainly caused by chronic cerebral hypoperfusion and subsequent white matter lesions. Noninvasive transcranial magnetic stimulation has been utilized in treating various neurological disorders. However, the function of theta-burst transcranial magnetic stimulation on VCID remains to be defined. We utilized 4-week bilateral carotid artery stenosis model of male mice to mimic VCID. Intermittent theta-burst stimulation (iTBS) or consecutive theta-burst stimulation (cTBS) was administered for 14 consecutive days. Through luxol fast blue staining, electron microscopy and immunofluorescence, we found that iTBS, not cTBS, significantly improved demyelination, axonal damage and β-amyloid deposition, without affecting cerebral blood flow in VCID mice. At cellular levels, iTBS rescued the loss of mature oligodendrocytes, promoted precursor cell differentiation, and inhibited pro-inflammatory activation of astrocytes and microglia. Notably, iTBS attenuated cognitive deterioration in both short-term retention and long-term spatial memory of VCID mice as indicated by serial neurobehavioral tests. To explore the molecular involvement of iTBS, mRNA sequencing was carried out. By real-time PCR and combined RNA fluorescence in situ hybridization with immunofluorescence, iTBS was confirmed to increase Rxrg expression specifically in mature oligodendrocytes. Collectively, iTBS could ameliorate vascular cognitive dysfunction, probably via mitigating white matter lesions and neuroinflammation in the corpus callosum. Rxrg signaling in mature oligodendrocytes, which was increased by iTBS, might be a potential target for VCID treatment.

The effect of real versus sham intermittent theta burst transcranial magnetic stimulation combined with conventional treatment on poststroke dysphagia: a randomized controlled trial.

Repetitive transcranial magnetic stimulation to the pharyngeal motor cortex has shown beneficial effects on poststroke dysphagia. Previous studies, however, using intermittent theta burst stimulation (iTBS) for dysphagia have targeted the suprahyoid motor cortex. This study aimed to investigate the effects of iTBS to the pharyngeal motor cortex in patients with poststroke dysphagia, using ultrasound and videofluoroscopic swallowing studies (VFSS). A randomized controlled trial was conducted on patients with dysphagia due to a first-time unilateral stroke. Patients who had signs and symptoms of dysphagia and showed aspiration or penetration on VFSS were included. Twenty-eight patients were randomly assigned to either real or sham iTBS groups, and each patient underwent five sessions of iTBS to the ipsilesional pharyngeal motor cortex. Each iTBS session was followed by conventional dysphagia treatment for 30 min. The hyoid-larynx approximation measured by ultrasound, penetration-aspiration scale (PAS) and functional dysphagia scale (FDS) assessed by VFSS were evaluated before and after completion of iTBS. There were no significant differences between the two groups in terms of demographic and clinical characteristics, including age and type of stroke. The hyoid-larynx approximation ratio increased in the real iTBS group and decreased in the sham iTBS group (median values of pre-post differences were 0.27 vs. -0.01, P < 0.001). The PAS and FDS showed greater improvements in the real iTBS group than in the sham iTBS group (median values of pre-post differences of the PAS were -2.50 vs. 0.00, P = 0.004; median values of pre-post differences of the FDS were -12.50 vs. -2.50, P < 0.001). No adverse effects were reported during or after iTBS sessions. Five-session iTBS to the pharyngeal motor cortex combined with conventional treatment led to a significant improvement in poststroke dysphagia in terms of hyoid-larynx approximation which is related to the suprahyoid muscle. Considering the short duration of one iTBS session, this can be an efficient and effective treatment tool for patients with this condition.

Parietal theta burst TMS does not modulate bistable perception.

The role of the parietal cortex in perceptual awareness and in resolving perceptual ambiguity is unsettled. Early influential transcranial magnetic stimulation studies have revealed differences in conscious perception following parietal stimulation, fuelling the notion that parietal cortex causally contributes to resolving perceptual ambiguity. However, central to this conclusion is the reliability of the method employed. Several prior studies have revealed opposing effects, such as shortening, lengthening, or no effect on multistable perceptual transitions following parietal stimulation. Here we addressed the reliability of continuous theta-burst stimulation (cTBS) on parietal cortex on the perception of bistable stimuli. We conducted three cTBS experiments that were matched to prior experiments in terms of stimuli, stimulation protocol, and target site, and used a higher number of participants. None of our cTBS experiments replicated prior cTBS results. The only experiment using individual functional localizers led to weak effects, while the two others led to null results. Individual variability of motor cortex cTBS did not predict parietal cTBS effects. In view of recent reports of highly variable cTBS effects over motor cortex, our results suggest that cTBS is particularly unreliable in modulating bistable perception when applied over parietal cortex.

Frontal and cerebellar contributions to pitch and rhythm processing: a TMS study.

Music represents a salient stimulus for the brain with two key features: pitch and rhythm. Few data are available on cognitive analysis of music listening in musically naïve healthy participants. Beyond auditory cortices, neuroimaging data showed the involvement of prefrontal cortex in pitch and of cerebellum in rhythm. The present study is aimed at investigating the role of prefrontal and cerebellar cortices in both pitch and rhythm processing. The performance of fifteen participants without musical expertise was investigated in a listening discrimination task. The task required to decide whether two eight-element melodic sequences were equal or different according to pitch or rhythm characteristics. Before the task, we applied a protocol of continuous theta burst transcranial magnetic stimulation interfering with the activity of the left cerebellar hemisphere (lCb), right inferior frontal gyrus (rIFG), or vertex (Cz-control site), in a within cross-over design. Our results showed that participants were more accurate in pitch than rhythm tasks. Importantly, the reaction times were slower following rIFG or lCb stimulations in both tasks. Notably, frontal and cerebellar stimulations did not induce any motor effect in right and left hand. The present findings point to the role of the fronto-cerebellar network in music processing with a single mechanism for both pitch and rhythm patterns.

Increasing striatal dopamine release through repeated bouts of theta burst transcranial magnetic stimulation of the left dorsolateral prefrontal cortex. A 18F-desmethoxyfallypride positron emission tomography study.

Transcranial Magnetic Stimulation (TMS) can modulate fronto-striatal connectivity in the human brain. Here Positron Emission Tomography (PET) and neuro-navigated TMS were combined to investigate the dynamics of the fronto-striatal connectivity in the human brain. Employing 18F-DesmethoxyFallypride (DMFP) - a Dopamine receptor-antagonist - the release of endogenous dopamine in the striatum in response to time-spaced repeated bouts of excitatory, intermittent theta burst stimulation (iTBS) of the Left-Dorsolateral Prefrontal Cortex (L-DLPFC) was measured. 23 healthy participants underwent two PET sessions, each one with four blocks of iTBS separated by 30 minutes: sham (control) and verum (90% of individual resting motor threshold). Receptor Binding Ratios were collected for sham and verum sessions across 37 time frames (about 130 minutes) in striatal sub-regions (Caudate nucleus and Putamen). Verum iTBS increased the dopamine release in striatal sub-regions, relative to sham iTBS. Dopamine levels in the verum session increased progressively across the time frames until frame number 28 (approximately 85 minutes after the start of the session and after three iTBS bouts) and then essentially remained unchanged until the end of the session. Results suggest that the short-timed iTBS protocol performed in time-spaced blocks can effectively induce a dynamic dose dependent increase in dopaminergic fronto-striatal connectivity. This scheme could provide an alternative to unpleasant and distressing, long stimulation protocols in experimental and therapeutic settings. Specifically, it was demonstrated that three repeated bouts of iTBS, spaced by short intervals, achieve larger effects than one single stimulation. This finding has implications for the planning of therapeutic interventions, for example, treatment of major depression.

Effects of right prefrontal theta-burst transcranial magnetic stimulation or transcranial direct current stimulation on apathy in patients with schizophrenia: A multicenter RCT

Apathy is a core negative symptom associated with an unfavorable functional outcome. Noninvasive brain stimulation has shown promise in the treatment of schizophrenia but has not been tested specifically for apathy.We conducted a randomized controlled trial of intermittent theta-burst (iTBS) transcranial magnetic stimulation and transcranial direct current stimulation (tDCS) targeted at the right dorsolateral prefrontal cortex (DLPFC) in patients diagnosed with a psychotic disorder suffering from apathy. The study was a multicenter, randomized, placebo-controlled, and rater-blinded trial. Patients (N = 88) were randomized into active iTBS, active tDCS, sham iTBS or sham tDCS treatment, daily for two weeks (excluding weekends). Effects were measured post-treatment and at four week and ten week follow-up. Primary outcome was apathy severity (Apathy Evaluation Scale, clinician-rated). Additional measures included assessment of negative symptoms, depression, anhedonia and quality of life.No significant difference in improvement of apathy or negative symptoms was observed for real versus sham treatment with either iTBS or tDCS, though all groups improved to a small extent. We conclude that two weeks of brain stimulation over the right DLPFC with either iTBS or tDCS is not effective for improving apathy or negative symptoms. Longer and more intensive protocols may yield different results.

Effects of continuous versus intermittent theta-burst TMS on fMRI connectivity.

Transcranial magnetic stimulation is a noninvasive technique that can be used to evoke distributed network-level effects. Previous work demonstrated that the Hippocampal-Cortical Network responds preferably (i.e., greater memory improvement and increases in hippocampal-network connectivity) to continuous theta-burst stimulation protocol relative to intermittent theta-burst and to 20-Hz rTMS. Here, these data were further analyzed to characterize effects of continuous versus intermittent theta-burst stimulation on network-level connectivity measures - as well as local connectedness - via resting-state fMRI. In contrast to theories that propose continuous and intermittent theta-burst cause local inhibitory versus excitatory effects, respectively, both protocols caused local decreases in fMRI connectivity around the stimulated parietal site. While iTBS caused decreases in connectivity across the hippocampal-cortical network, cTBS caused increases and decreases in connectivity across the network. cTBS had no effect on the parietal-cortical network, whereas iTBS caused decreases in the right parietal cortex (contralateral hemisphere to the stimulation target). These findings suggest that continuous theta-burst may have entrained the endogenous hippocampal-cortical network, whereas the intermittent train was unable to maintain entrainment that may have yielded the long-lasting effects measured in this study (i.e., within 20-min post-stimulation). Furthermore, these effects were specific to the hippocampal-cortical network, which has a putative endogenous functionally-relevant theta rhythm, and not to the parietal network. These results add to the growing body of evidence that suggests effects of theta-burst stimulation are not fully characterized by excitatory/inhibitory theories. Further work is required to understand local and network-level effects of noninvasive stimulation.

TMS disruption ofthe lateral prefrontal cortex increases neural activity inthe default mode network when naming facial expressions.

Recognizing facial expressions is dependent on multiple brain networks specialized for different cognitive functions. In the current study, participants (N = 20) were scanned using functional magnetic resonance imaging (fMRI), while they performed a covert facial expression naming task. Immediately prior to scanning thetaburst transcranial magnetic stimulation (TMS) was delivered over the right lateral prefrontal cortex (PFC), or the vertex control site. A group whole-brain analysis revealed that TMS induced opposite effects in the neural responses across different brain networks. Stimulation of the right PFC (compared to stimulation of the vertex) decreased neural activity in the left lateral PFC but increased neural activity in three nodes of the default mode network (DMN): the right superior frontal gyrus, right angular gyrus and the bilateral middle cingulate gyrus. A region of interest analysis showed that TMS delivered over the right PFC reduced neural activity across all functionally localised face areas (including in the PFC) compared to TMS delivered over the vertex. These results suggest that visually recognizing facial expressions is dependent on the dynamic interaction of the face-processing network and the DMN. Our study also demonstrates the utility of combined TMS/fMRI studies for revealing the dynamic interactions between different functional brain networks.

Continuous Theta Burst Transcranial Magnetic Stimulation in Treating Post-Stroke Insomnia Monitored by Polysomnography: A Case Report

Continuous Theta Burst Transcranial Magnetic Stimulation in Treating Post-Stroke Insomnia Monitored by Polysomnography: A Case Report

Time-on-task effects on human pupillary and saccadic metrics after theta burst transcranial magnetic stimulation over the frontal eye field

Pupil size undergoes constant changes primarily influenced by ambient luminance. These changes are referred to as the pupillary light reflex (PLR), where the pupil transiently constricts in response to light. PLR kinematics provides valuable insights into autonomic nervous system function and have significant clinical applications. Recent research indicates that attention plays a role in modulating the PLR, and the circuit involving the frontal eye field (FEF) and superior colliculus is causally involved in controlling this pupillary modulation. However, there is limited research exploring the role of the human FEF in these pupillary responses, and its impact on PLR metrics remains unexplored. Additionally, although the protocol of continuous theta-burst stimulation (cTBS) is well-established, the period of disruption after cTBS is yet to be examined in pupillary responses. Our study aimed to investigate the effects of FEF cTBS on pupillary and saccadic metrics in relation to time spent performing a task (referred to as time-on-task). We presented a bright stimulus to induce the PLR in visual- and memory-delay saccade tasks following cTBS over the right FEF or vertex. FEF cTBS, compared to vertex cTBS, resulted in decreased baseline pupil size, peak constriction velocities, and amplitude. Furthermore, the time-on-task effects on baseline pupil size, peak amplitude, and peak time differed between the two stimulation conditions. In contrast, the time-on-task effects on saccadic metrics were less pronounced between the two conditions. In summary, our study provides the first evidence that FEF cTBS affects human PLR metrics and that these effects are modulated by time-on-task.

Predictive role of impulsivity, anxiety, and depression in the efficacy of intermittent theta burst transcranial magnetic stimulation modalities for treating methamphetamine use disorder: A randomized clinical trial

IntroductionMethamphetamine use disorder (MUD) can cause impulsive behavior, anxiety, and depression. Stimulation of the left dorsolateral prefrontal cortex in MUD patients by intermittent theta burst repetitive transcranial magnetic stimulation (iTBS-rTMS) is effective in reducing cravings, impulsive behavior, anxiety, and depression. The purpose of this study was to explore whether these psychological factors helped to predict MUD patients' responses to iTBS-rTMS treatment. MethodsFifty MUD patients and sixty healthy subjects matched for general conditions were used as study subjects. The study randomly divided MUD patients into iTBS-rTMS and sham stimulation groups and received 20 sessions of real or sham iTBS-rTMS treatment, and the study collected cue-related evoked craving data before and after treatment. All subjects completed the Barratt Impulsiveness Scale (BIS-11), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). ResultsThe MUD patients showed significantly higher levels of impulsivity, anxiety, and depression than the healthy subjects. The MUD patients who received the real treatment had significantly lower impulsivity, anxiety, and depression scores, and better treatment effects on cravings than the sham stimulation group. The Spearman rank correlation and stepwise multiple regression analyses showed that the baseline BIS-11 and the reduction rate (RR) of BIS-11 and RR of SDS were positively correlated with the decrease in cravings in the iTBS-rTMS group. ROC curve analysis showed that RR of SDS (AUC = 91.6 %; 95 % CI = 0.804–1.000) had predictive power to iTBS- rTMS therapeutic efficacy, the cutoff value is 15.102 %. ConclusionsiTBS-rTMS had a good therapeutic effect in MUD patients and the baseline impulsivity, the improved depression and impulsivity were associated with therapeutic effect of iTBS-rTMS. The improved depression had the potential to predict the efficacy of the iTBS-rTMS modality for MUD treatment.

Brain connectivity-guided, Optimised theta burst transcranial magnetic stimulation to improve Central Pain Modulation in knee Osteoarthritis Pain (BoostCPM): protocol of a pilot randomised clinical trial in a secondary care setting in the UK

IntroductionChronic pain is a common health problem that is not efficiently managed by standard analgesic treatments. There is evidence that treatment resistance may result from maladaptive brain changes in areas...

Role ofmedial prefrontal cortex andprimary somatosensory cortex inself andother-directed vicarious social touch: a TMS study.

Conflicting evidence points to the contribution of several key nodes of the 'social brain' to the processing of both discriminatory and affective qualities of interpersonal touch. Whether the primary somatosensory cortex (S1) and the medial prefrontal cortex (mPFC), two brain areas vital for tactile mirroring and affective mentalizing, play a functional role in shared representations of C-tactile (CT) targeted affective touch is still a matter of debate. Here, we used offline continuous theta-burst transcranial magnetic stimulation (cTBS) to mPFC, S1 and vertex (control) prior to participants providing ratings of vicarious touch pleasantness for self and others delivered across several body sites at CT-targeted velocities. We found that S1-cTBS led to a significant increase in touch ratings to the self, with this effect being positively associated to levels of interoceptive awareness. Conversely, mPFC-cTBS reduced pleasantness ratings for touch to another person. These effects were not specific for CT-optimal (slow) stroking velocities, but rather they applied to all types of social touch. Overall, our findings challenge the causal role of the S1 and mPFC in vicarious affective touch and suggest that self- vs other-directed vicarious touch responses might crucially depend on the specific involvement of key social networks in gentle tactile interactions.

Effects of intermittent theta-burst transcranial magnetic stimulation on post-traumatic stress disorder symptoms: A randomized controlled trial

Post-traumatic stress disorder (PTSD) is a prevalent and debilitating illness, which can be alleviated by transcranial magnetic stimulation (TMS). Intermittent theta burst stimulation (iTBS), a newer form of repetitive transcranial magnetic stimulation (rTMS), offers the advantage of shorter treatment sessions compared to the standard 10 Hz rTMS treatment. In order to compare the two forms of TMS, we enrolled 75 participants aged between 18 and 55 years who presented with (PCL-C) scale score of at least 50. Participants were randomly assigned to groups in a ratio of 1:1:1, receiving either 10 Hz rTMS, iTBS, or sham-controlled iTBS. Participants in the two treatment groups underwent 15 therapies which consisted of 1800 pulses and targeted the right dorsolateral prefrontal cortex (DLPFC). The main outcomes included changes in scores on the PCL-C and the Post-Traumatic Growth Inventory (PTGI). After intervention, the PCL-C and PTGI scores in iTBS and rTMS groups were significantly different from those in sham-controlled iTBS group. No significant differences in PCL-C and PTGI were found between the two active treatment groups. ITBS, with a shorter treatment duration, can effectively improve the symptoms of PTSD, with no significant difference in effect from that of rTMS. Future studies need to further elucidate the mechanisms, optimize the parameters and investigate the therapeutic potential and efficacy of iTBS in PTSD.

Treatment-resistant depression: definition, prevalence, detection, management, and investigational interventions.

Treatment-resistant depression (TRD) is common and associated with multiple serious public health implications. A consensus definition of TRD with demonstrated predictive utility in terms of clinical decision-making and health outcomes does not currently exist. Instead, a plethora of definitions have been proposed, which vary significantly in their conceptual framework. The absence of a consensus definition hampers precise estimates of the prevalence of TRD, and also belies efforts to identify risk factors, prevention opportunities, and effective interventions. In addition, it results in heterogeneity in clinical practice decision-making, adversely affecting quality of care. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have adopted the most used definition of TRD (i.e., inadequate response to a minimum of two antidepressants despite adequacy of the treatment trial and adherence to treatment). It is currently estimated that at least 30% of persons with depression meet this definition. A significant percentage of persons with TRD are actually pseudo-resistant (e.g., due to inadequacy of treatment trials or non-adherence to treatment). Although multiple sociodemographic, clinical, treatment and contextual factors are known to negatively moderate response in persons with depression, very few factors are regarded as predictive of non-response across multiple modalities of treatment. Intravenous ketamine and intranasal esketamine (co-administered with an antidepressant) are established as efficacious in the management of TRD. Some second-generation antipsychotics (e.g., aripiprazole, brexpiprazole, cariprazine, quetiapine XR) are proven effective as adjunctive treatments to antidepressants in partial responders, but only the olanzapine-fluoxetine combination has been studied in FDA-defined TRD. Repetitive transcranial magnetic stimulation (TMS) is established as effective and FDA-approved for individuals with TRD, with accelerated theta-burst TMS also recently showing efficacy. Electroconvulsive therapy is regarded as an effective acute and maintenance intervention in TRD, with preliminary evidence suggesting non-inferiority to acute intravenous ketamine. Evidence for extending antidepressant trial, medication switching and combining antidepressants is mixed. Manual-based psychotherapies are not established as efficacious on their own in TRD, but offer significant symptomatic relief when added to conventional antidepressants. Digital therapeutics are under study and represent a potential future clinical vista in this population.

Neuronavigated 20hz theta burst TMS for OCD comorbid with depression and anxiety sequentially targeting RDLPFC, LDLPFC, and ROFC

Neuronavigated 20hz theta burst TMS for OCD comorbid with depression and anxiety sequentially targeting RDLPFC, LDLPFC, and ROFC

Effects of Hyperdirect Pathway Theta Burst Transcranial Magnetic Stimulation on Inhibitory Control, Craving, and Smoking in Adults With Nicotine Dependence: A Double-Blind, Randomized Crossover Trial

BackgroundNicotine dependence is associated with dysregulated hyperdirect pathway (HDP)–mediated inhibitory control (IC). However, there are currently no evidence-based treatments that have been shown to target the HDP to improve IC and reduce cigarette cravings and smoking. MethodsFollowing a baseline nonstimulation control session, this study (N = 37; female: n = 17) used a double-blind, randomized crossover design to examine the behavioral and neural effects of intermittent theta burst stimulation (iTBS) and continuous TBS (cTBS) to the right inferior frontal gyrus (rIFG)—a key cortical node of the HDP. Associations between treatment effects were also explored. ResultsAt baseline, HDP IC task-state functional connectivity was positively associated with IC task performance, which confirmed the association between HDP circuit function and IC. Compared with iTBS, rIFG cTBS improved IC task performance. Compared with the baseline nonstimulation control session, both TBS conditions reduced cigarette craving and smoking; however, although craving and smoking were lower for cTBS, no differences were found between the two active conditions. In addition, although HDP IC task-state functional connectivity was greater following cTBS than iTBS, there was no significant difference between conditions. Finally, cTBS-induced improvement in IC task performance was associated with reduced craving, and cTBS-induced reduction in craving was associated with reduced smoking. ConclusionsThese findings warrant further investigation into the effects of rIFG cTBS for increasing IC and reducing craving and smoking among individuals with nicotine dependence. Future sham-controlled cTBS studies may help further elucidate the mechanisms by which rIFG cTBS mediates IC and smoking behavior.

DLPFC-PPC-cTBS effects on metacognitive awareness

BackgroundNeuroimaging and lesion studies suggested that the dorsolateral prefrontal and posterior parietal cortices mediate visual metacognitive awareness. The causal evidence provided by non-invasive brain stimulation, however, is inconsistent. Objective/hypothesisHere we revisit a major figure discrimination experiment adding a new Kanizsa figure task trying to resolve whether bilateral continuous theta-burst transcranial magnetic stimulation (cTBS) over these regions affects perceptual metacognition. Specifically, we tested whether subjective visibility ratings and/or metacognitive efficiency are lower when cTBS is applied to these two regions in comparison to an active control region. MethodsA within-subjects design including three sessions spaced by one-week intervals was implemented. In each session, every participant was administered bilateral cTBS to either prefrontal, control or parietal cortices. Two concurrent tasks were performed, a real and an illusory figure task, stabilising objective performance with use of an adaptive staircase procedure. ResultsWhen performing the replicated task, cTBS was found insufficient to disrupt neither visibility ratings nor metacognitive efficiency. However, with use of Kanizsa style illusory figures, cTBS over the dorsolateral prefrontal, but not over the posterior parietal cortex, was observed to significantly diminish metacognitive efficiency. Conclusion(s)Real and illusory figure tasks demonstrated different cTBS effects. A possible explanation is the involvement of the prefrontal cortex in the creation of expectations, which is necessary for efficient metacognition. Failure to replicate previous findings for the real figure task, however, cannot be said to support, conclusively, the notion that these brain regions have a causal role in metacognitive awareness. This inconsistent finding may result from certain limitations of our study, thereby suggesting the need for yet further investigation.

Human microsaccade cueing modulation in visual- and memory-delay saccade tasks after theta burst transcranial magnetic stimulation over the frontal eye field

Microsaccades that occur during periods of fixation are modulated by various cognitive processes and have an impact on visual processing. A network of brain areas is involved in microsaccade generation, including the superior colliculus and frontal eye field (FEF) which are involved in modulating microsaccade rate and direction after the appearance of a visual cue (referred to as microsaccade cueing modulation). Although the neural mechanisms underlying microsaccade cueing modulations have been demonstrated in monkeys, limited research has investigated a causal role of these areas in humans. By applying continuous theta-burst transcranial magnetic stimulation (cTBS) over the right FEF and vertex, we investigated the role of human FEF in modulating microsaccade responses after the appearance of a visual target in a visual- and memory-delay saccade task. After target appearance, microsaccade rate was initially suppressed but then increased in both cTBS conditions. More importantly, in the visual-delay task, microsaccades after target appearance were directed to the ipsilateral side more often with FEF, compared to vertex stimulation. Moreover, microsaccades were directed towards the target location, then to the opposite location of the target in both tasks, with larger effects in the visual-, compared to, memory-delay task. This microsaccade direction modulation was delayed after FEF stimulation in the memory-delay task. Overall, some microsaccade cueing modulations were moderately disrupted after FEF cTBS, suggesting a causal role for involvement of the human FEF in microsaccade generation after presentation of salient stimuli.

Efficacy of adjunctive theta burst transcranial magnetic stimulation in acute mania: A randomized and placebo-controlled study

Objectives: Transcranial magnetic stimulation (TMS) has been suggested as a non-invasive stimulation treatment modality in bipolar disorder. However, the efficacy of repetitiver TMS in acute phase mania is unclear. The aim of this study is to assess the efficacy of theta burst stimulation (TBS) as an add-on therapy in the treatment of acute phase mania stimulation both right and left dorsolateral prefrontal cortex (DLPFC) in a randomized and sham-controlled design. Material and Methods: Forty right-handed patients between 18 and 59 years were randomly allocated to active and sham groups. Then, intermittent TBS (right DLPFC) and cTBS (left DLPFC) sessions (half an hour apart) were delivered in two sessions per day for 5 days in a week. Youngs Mania Rating Scale (YMRS) and Clinical global impression-Bipolar Disorder (CGI-BP) were assessed at baseline and at 7th and 21st days. Results: Our study fails to show a significant effect on of active stimulation in comparison to sham over psychopathology YMRS (F = 0.300; P ≤ 0.612), CGIBP-S (F = 0.432; P = 0.562), CGIBP-P (F = 0.202; P = 0.701), and CGIBP-W (F = 200; P = 0.705) in intention to treat protocol across 21 days. Minimal side effects were reported and none of the patients discontinued TBS citing side effects. Conclusion: We conclude that it is safe and well tolerated yet has inconclusive short-term therapeutic benefits. Trials using better localization technique with large sample, longer duration, and better dosing protocols are needed.