A systematic review of transcranial magnetic stimulation in the treatment of functional (conversion) neurological symptoms

Electrical safety assessment of a prototype device for electromagnetic stimulation of the ear in patients with tinnitus

<b><br>Aim:</b> The aim of the study was to evaluate the results of electrical safety results of a prototype electromagnetic ear stimulation device in patients with tinnitus.</br> <b><br>Material and methods:</b> The electrical safety tests of the prototype device for electro- and magnetostimulation of the hearing organ were carried out at the Center for Attestation and Certification Tests in Gliwice. The tests concerned selected parameters including the PN-EN standard.</br> <b><br>Results:</b> Safety studies of the prototype electrical stimulation device for the ear in patients with tinnitus were necessary to perform the planned further preclinical studies. Obtained results regarding: identification and labeling of the device; protection against electric shock; checking protective earthing, functional earthing and potential equalization; checking the leakage current and auxiliary currents of the patient; checking the distances through the solid insulation and the use of thin insulating spacers; checking the electrical strength of the device insulation; checking protection against mechanical hazards of the device; checking the risk associated with surfaces, corners and edges, and checking the protection against excessive temperatures and other threats comply with the standard PN-EN.</br> <b><br>Conclusions:</b> No risk to the patient and medical staff. Tests of protection against mechanical hazards of the device have shown that the only movable part whose contact with the patient could cause an unacceptable risk is the fan installed inside the housing.</br>.

Evaluation the results of electromagnetic compatibility of a prototype device for ear stimulation in patients with tinnitus

<b><br>Aim:</b> The aim of the study was to evaluate the results of electromagnetic compatibility of a prototype device for ear stimulation in patients with tinnitus.</br> <b><br>Material and methods:</b> The electromagnetic compatibility tests of the prototype device for electro- and magnetostimulation of the hearing organ were carried out at the Center for Attestation and Certification Tests OBAC Sp. z o. o. in Gliwice in 2020. The following product standards were used: PN-EN 60601-1-2:2015-11 - medical electrical equipment (general requirements for basic safety and essential functioning; PN-EN 55011:2012 - industrial, scientific and medical equipment [characteristics of radio frequency disturbances] ) PN-EN 61000-3-2:2014-10 - electromagnetic compatibility (EMC), permissible levels of harmonic current emissions (phase load current ≤ 16 A).</br> <b><br>Results:</b> The level of expanded uncertainty in the measurement of conducted disturbances in the range of 0.150-30MHz does not exceed the level specified in the PN-EN-55016-4-2:2011 standard. In the study of the emission of radiated disturbances up to 1GHz in the frequency range of 30-1000MHz (PN-EN 55011:2012 standard), it was found that the setting of the EUT during the tests was in accordance with the requirements of the standard. The level of expanded uncertainty in the measurement of radiated disturbances in the 30-1000MHz range does not exceed the level specified in the PN-EN 55016-4-2:2011 standard. The measured current harmonic levels (phase power supply current ≤16A) with a frequency range of 50Hz-2kHz do not exceed the permissible levels specified in the PN-EN 61000-3-2:2014-10 standard. The test of resistance to the magnetic field at the frequency of the power grid (PN-EN 61000-4-8: 2010 standard also showed that the setting of the EUT during the tests was in accordance with the requirements of the standard and the result was positive.</br> <b><br>Conclusions:</b> Testing of immunity to radiated radio frequency electromagnetic field (PN-EN 61000-4-3:2007 +A1:2008+A2:2011 standard) and testing of resistance to magnetic field at power frequency (PN-EN 61000-4-8 standard :2010) did not exceed the level specified in the standard and showed a positive result. The measured harmonic levels of the network current (phase supply current ≤16A) with the frequency range 50Hz-2kHz do not exceed the permissible levels specified in the PN-EN 61000- 3-2:2014-10 standard for a class A device.</br>.

Disrupting nociceptive information processing flow through transcranial focused ultrasound neuromodulation of thalamic nuclei

BACKGROUND

MRI-guided transcranial focused ultrasound (MRgFUS) as a next-generation neuromodulation tool can precisely target and stimulate deep brain regions with high spatial selectivity. Combined with MR-ARFI (acoustic radiation force imaging) and using fMRI BOLD signal as functional readouts, our previous studies have shown that low-intensity FUS can excite or suppress neural activity in the somatosensory cortex.

OBJECTIVE

To investigate whether low-intensity FUS can suppress nociceptive heat stimulation-induced responses in thalamic nuclei during hand stimulation, and to determine how this suppression influences the information processing flow within nociception networks.

FINDINGS

BOLD fMRI activations evoked by 47.5 °C heat stimulation of hand were detected in 24 cortical regions, which belong to sensory, affective, and cognitive nociceptive networks. Concurrent delivery of low-intensity FUS pulses (650 kHz, 550 kPa) to the predefined heat nociceptive stimulus-responsive thalamic centromedial_parafascicular (CM_para), mediodorsal (MD), ventral_lateral (VL_ and ventral_lateral_posteroventral (VLpv) nuclei suppressed their heat responses. Off-target cortical areas exhibited reduced, enhanced, or no significant fMRI signal changes, depending on the specific areas. Differentiable thalamocortical information flow during the processing of nociceptive heat input was observed, as indicated by the time to reach 10% or 30% of the heat-evoked BOLD signal peak. Suppression of thalamic heat responses significantly altered nociceptive processing flow and direction between the thalamus and cortical areas. Modulation of contralateral versus ipsilateral areas by unilateral thalamic activity differed. Signals detected in high-order cortical areas, such as dorsal frontal (DFC) and ventrolateral prefrontal (vlPFC) cortices, exhibited faster response latencies than sensory areas.

CONCLUSIONS

The concurrent delivery of FUS suppressed nociceptive heat response in thalamic nuclei and disrupted the nociceptive network. This study offers new insights into the causal functional connections within the thalamocortical networks and demonstrates the modulatory effects of low-intensity FUS on nociceptive information processing.

[Validated care programs for patients with functional neurological disorders]

Functional neurological disorder (FND) is a common cause of persistent and disabling neurological symptoms. Diagnostic delay may lead to no treatment, inappropriate treatment or even iatrogenic symptoms. Yet, several treatments significantly reduce physical symptoms and improve functioning in FND patients even though not all patients respond to the currently available treatments. This review aims to describe the range of evidence-based rehabilitative and/or psychological therapeutic approaches available for FND patients. The most effective treatments are multidisciplinary and coordinated; using an outpatient or inpatient setting. Building a network of FND-trained healthcare professionals around the patient is an essential aspect of optimal patient management. Indeed, a supportive environment coupled with a collaborative therapeutic relationship improves understanding of FND and appears to help patients engage in appropriate treatments. Patients need to be invested in their own care and have to understand that recovery may depend on their commitment. The conventional treatment combines psychoeducation, physical rehabilitation and psychotherapy (cognitive and behavioral therapy, hypnosis, psychodynamic interpersonal therapy). Early referral of patients to physical therapy is recommended; however, the optimal parameters of treatment, duration and intensity are unknown and seem to vary with the severity and chronicity of symptoms. The goal is to minimize self-awareness by diverting attention or by stimulating automatically generated movements with non-specific and gradual exercises. The use of compensatory technical aids should be avoided as much as possible. Psychotherapeutic management should encourage self-evaluation of cognitive distortions, emotional reactions and maladaptive behaviors while empowering the patient in managing symptoms. Symptom management can use anchoring strategies to fight against dissociation. The aim is to connect to the immediate environment and to enrich one's sensoriality. The psychological interventions should then be adapted to the individual psychopathology, cognitive style and personality functioning of each patient. There is currently no known curative pharmacological treatment for FND. The pharmacological approach rather consists of progressively discontinuing medication that was introduced by default and that could lead to undesirable side effects. Finally, neurostimulation (transcranial magnetic stimulation, transcranial direct current stimulation) can be effective on motor FND.

Functional Neurologic Disorders, disorders to be managed by neurologists, or are neurologists wandering in a dangerous field with inadequate resources?

In recent years, some neurologists reconsidered their approach to Medically Unexplained Symptoms and proposed Functional Neurologic Disorders (FND) as a new entity, claiming that neurology could offer alternative treatment options to the psychotherapies provided in psychiatry settings. FNDs, for this purpose, should include only the disorders listed as Conversion from the Somatic Symptom and Related Disorders (SSRD) group. The present review analyzes the rationale of this position and challenges the arguments provided for its support. The review also discusses the systematization of these disorders as provided by public health systems. It outlines risks stemming from economic support and public funding uncertainty, given their negligible epidemiological dimensions resulting from the parcellation of SSRD. The review underlines the unresolved issue of Factitious Disorders, which are in the same SSRD category of the international classification but are, nonetheless, overlooked by the theoretical proponents of the FND entity. Comorbidity with other psychiatric disorders is also analyzed. We propose a model that supports the continuum between different SSRD conditions, including Factitious Disorders. The model is based on the emergence of feigned death reflex and deception from frontal lobe dysfunction. Finally, the paper summarizes the wealth of historical psychiatric and psychodynamic approaches and critical reviews. The study also puts in context the categorization and interpretation efforts provided by the most eminent researchers of the past century.

The clinical management of functional neurological disorder: A scoping review of the literature

OBJECTIVE

To date, there have been no reviews bringing together evidence on the clinical management of functional neurological disorder (FND) and patients', caregivers', and healthcare workers' experiences. This review provides an overview of the literature focused on the clinical management of FND.

METHODS

Four databases were searched, and a consultation exercise was conducted to retrieve relevant records dated from September 2010 to September 2020. Articles documenting diagnostic methods, treatments or interventions, or the experiences and perspectives of patients and healthcare workers in the clinical management of FND were included.

RESULTS

In total, 2756 records were retrieved, with 162 included in this review. The diagnostic methods reported predominantly included positive clinical signs, v-EEG and EEG. Psychological treatments and medication were the most reported treatments. Mixed findings of the effectiveness of CBT were found. Haloperidol, physiotherapy and scripted diagnosis were found to be effective in reducing FND symptoms. Several facilitators and barriers for patients accessing treatment for FND were reported.

CONCLUSION

The literature describing the clinical management for FND has increased considerably in recent times. A wide variety of diagnostic tools and treatments and interventions were found, with more focus being placed on tests that confirm a diagnosis than 'rule-out' tests. The main treatment type found in this review was medication. This review revealed that there is a lack of high-quality evidence and reflects the need for official clinical guidelines for FND, providing healthcare workers and patients the support needed to navigate the process to diagnose and manage FND.

Assessment of Subjective Tinnitus Treatment Results Using a Prototype Device for Electrical and Magnetic Stimulation of the Ear-Preliminary Study

Background: The aim of the study was to evaluate the effectiveness of subjective tinnitus treatment in patients with cochlear sensorineural hearing loss with magnetic ear stimulation using a prototype device. Since the 1970s, studies have been conducted on the use of electrical stimulation of the ear in the treatment of tinnitus. The available literature contains various hypotheses about the influence of electrical stimulation of the ear on tinnitus. Material and Methods: Preclinical studies were performed for 100 patients, 40 women and 60 men (124 ears in total), aged 38-72 years, treated for tinnitus. A subjective assessment of the loudness of tinnitus was performed, and the frequency and intensity as well as hearing threshold were determined using a prototype device for electro-magnetic stimulation of the ear. The treatment cycle consisted of 10 five-minute stimulations performed daily 5 times a week. Results: Before treatment, persistent tinnitus was found in 100 ears (80.6%) and periodic tinnitus in 24 ears (19.4%). Immediately after treatment, persistent tinnitus was present only in 50 ears (40.3%) and periodic tinnitus in 40 ears (32.3%). Complete resolution of tinnitus was noted in 34 ears (27.4%). On the other hand, the examination performed 3 months after the treatment showed persistent tinnitus in 40 ears (32.3%) and periodic tinnitus in 50 ears (40.3%), and complete resolution of tinnitus was recorded in 34 ears (27.4%). Based on the VAS analog scale, there was an improvement in tinnitus in 98 ears (79.0%) immediately after treatment and no improvement in 26 ears (20.0%). The mean VAS scale before treatment was 4.9 points, after treatment it was 2.1 points and 3 months after treatment it was 1.9 points. Conclusions: The preliminary research results show the high effectiveness of magnetic stimulation in the treatment of tinnitus with the use of a prototype device for electromagnetic stimulation of the ear. There was no negative effect of the stimulation on hearing or tinnitus.

Transcranial Magnetic Stimulation for the Neurological Patient: Scientific Principles and Applications

Non-invasive brain stimulation has been increasingly recognized for its potential as an investigational, diagnostic and therapeutic tool across the clinical neurosciences. Transcranial magnetic stimulation (TMS) is a non-invasive method of focal neuromodulation. Diagnostically, TMS can be used to probe cortical excitability and plasticity, as well as for functional mapping. Therapeutically, depending on the pattern employed, TMS can either facilitate or inhibit stimulated cortex potentially modulating maladaptive physiology through its effects on neuroplasticity. Despite this potential, applications of TMS in neurology have only been approved for diagnostic clinical neurophysiology, pre-surgical mapping of motor and language cortex, and the treatment of migraines. In this article, we discuss the principles of TMS and its clinical applications in neurology, including experimental applications in stroke rehabilitation, seizures, autism spectrum disorder, neurodegenerative disorders, movement disorders, tinnitus, chronic pain and functional neurological disorder. To promote increased cross-talk across neurology and psychiatry, we also succinctly review the TMS literature for the treatment of major depression and obsessive compulsive disorder. Overall, we argue that larger clinical trials that are better informed by circuit-level biomarkers and pathophysiological models will lead to an expansion of the application of TMS for patients cared for by neurologists.

Neuromodulation for the treatment of functional neurological disorder and somatic symptom disorder: a systematic review

Functional neurological disorder and somatic symptom disorder are complex neuropsychiatric conditions that have been linked to circuit-based dysfunction of brain networks. Neuromodulation is a novel therapeutic strategy capable of modulating relevant brain networks, making it a promising potential candidate for the treatment of these patient populations. We conducted a systematic review of Medline, Embase and PsycINFO up to 4 March 2021. Trials investigating neuromodulation devices for the treatment of functional neurological disorder or somatic symptom disorder were selected. Extracted variables included study design, demographic and clinical characteristics, psychiatric comorbidity, neurostimulation protocols, clinical outcome measures and results. 404 studies were identified with 12 meeting inclusion criteria. 221 patients were treated in the included studies with mean study sample size of 18 (4-70). Five studies were randomised clinical trials. Functional motor symptoms (six weakness, four movement disorders) were the most studied subpopulations. Transcranial magnetic stimulation (TMS) was the most frequently used device (10 studies), followed by electroconvulsive therapy (one study) and direct-current stimulation (one study). Treatment protocols varied in intended therapeutic mechanism(s): eight studies aimed to modulate underlying network dysfunction, five aimed to demonstrate movement (one also leveraged the former) and three boosted their primary mechanism with enhanced suggestion/expectation. All but one study reported positive results; however, methodological/outcome heterogeneity, mixed study quality and small sample sizes precluded quantitative meta-analysis. Neuromodulation, particularly TMS for the treatment of functional motor symptoms, shows preliminary promise in a growing line of research. Larger, sham-controlled studies are needed to further establish efficacy and better understand therapeutic mechanisms.

Repetitive transcranial magnetic stimulation for patients with functional paralysis: a randomized controlled study

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has been proposed to treat functional neurological disorders. Here, we aim to assess the efficacy of rTMS to treat functional paralysis in a controlled randomized trial.

METHODS

Patients received 2 sessions of active or sham 0.25 Hz rTMS (60 stimuli each), with a one-day interval, applied over the motor cortex contralateral to the paralysis. The primary outcome was the number of patients with an increase in motor score between baseline and after the second rTMS session, rated by two investigators blinded to the treatment allocation. Secondary outcomes were changes in global and fine motor scores between groups after rTMS, and occurrence of adverse events.

RESULTS

Sixty-two patients (46 female; mean [SD] age, 35.2 [13.9] years) were enrolled and randomized. Thirteen out of 32 (41%) and 11/30 (37%) patients had increased motor strength after active or sham rTMS, respectively (p=0.80). Changes in both global and fine motor scores after rTMS relative to baseline were also not significantly different between treatment groups (median difference in the global motor score 0.62 [0.83] and 0.37 [0.61], and fine motor scores 0.12 [0.18] and 0.08 [0.11], in active and sham rTMS groups, respectively, p=0.14). We observed six serious adverse events, consisting of 3 cephalalgia in the active group and 2 cephalalgia and 1 asthenia in the sham group.

CONCLUSIONS

Two sessions of sham or active low frequency rTMS were effective to improve functional paralysis, suggesting a placebo effect of this non-invasive brain stimulation technique.

Neurostimulation for the treatment of functional neurological disorder: A systematic review

Functional Neurological Disorder (FND), also known as conversion disorder, is characterized by neurological symptoms that are incompatible with any known structural disorder and best explained by a biopsychosocial model. Evidence-based treatments for FND are limited, with cognitive behavioral therapy (CBT) and physiotherapy being the most effective interventions [1]. In recent years, functional neuroimaging studies have provided robust evidence of alterations in activity and connectivity in multiple brain networks in FND. This body of evidence suggests that neurocircuitry-based interventions, such as non-invasive brain stimulation techniques (NIBS), may also represent an effective therapeutic option for patients with FND. In this systematic review, we outline the current state of knowledge of NIBS in FND, and discuss limitations and future directions that may help establish the efficacy of NIBS as a therapeutic option for FND.

Transcranial Magnetic Stimulation in Tremor Syndromes: Pathophysiologic Insights and Therapeutic Role

Transcranial magnetic stimulation (TMS) is a painless, non-invasive, and established brain stimulation technique to investigate human brain function. Over the last three decades, TMS has shed insight into the pathophysiology of many neurological disorders. Tremor is an involuntary, rhythmic oscillatory movement disorder commonly related to pathological oscillations propagated via the cerebello-thalamo-cortical pathway. Although tremor is the most common movement disorder and recent imaging studies have enhanced our understanding of the critical pathogenic networks, the underlying pathophysiology of different tremor syndromes is complex and still not fully understood. TMS has been used as a tool to further our understanding of tremor pathophysiology. In addition, repetitive TMS (rTMS) that can modulate brain functions through plasticity effects has been targeted to the tremor network to gain potential therapeutic benefits. However, evidence is available for only a few studies that included small patient samples with limited clinical follow-up. This review aims to discuss the role of TMS in advancing the pathophysiological understanding as well as emerging applications of rTMS for treating individual tremor syndromes. The review will focus on essential tremor, Parkinson's disease tremor, dystonic tremor syndrome, orthostatic tremor, and functional tremor.

Corticolimbic Modulation via Intermittent Theta Burst Stimulation as a Novel Treatment for Functional Movement Disorder: A Proof-of-Concept Study

Neuroimaging studies suggest that corticolimbic dysfunctions, including increased amygdala reactivity to emotional stimuli and heightened fronto-amygdala coupling, play a central role in the pathophysiology of functional movement disorders (FMD). Transcranial magnetic stimulation (TMS) has the potential to probe and modulate brain networks implicated in neuropsychiatric disorders, including FMD. Therefore, the objective of this proof-of-concept study was to investigate the safety, tolerability and preliminary efficacy of fronto-amygdala neuromodulation via targeted left prefrontal intermittent theta burst stimulation (iTBS) on brain and behavioral manifestations of FMD. Six subjects with a clinically defined diagnosis of FMD received three open-label iTBS sessions per day for two consecutive study visits. Safety and tolerability were assessed throughout the trial. Amygdala reactivity to emotionally valenced stimuli presented during an fMRI task and fronto-amygdala connectivity at rest were evaluated at baseline and after each stimulation visit, together with subjective levels of arousal and valence in response to affective stimuli. The FMD symptom severity was assessed at baseline, during treatment and 24 h after the last iTBS session. Multiple doses of iTBS were well-tolerated by all participants. Intermittent TBS significantly decreased fronto-amygdala connectivity and influenced amygdala reactivity to emotional stimuli. These neurocircuitry changes were associated to a marked reduction in FMD symptom severity. Corticolimbic modulation via iTBS represents a promising treatment for FMD that warrants additional research.

[Augmented psychotherapy with rTMS in functional neurological disorder]

BACKGROUND

We report the observation of a 47-year-old woman with functional neurological disorder (tetraparesis, mixed tremors and non-epileptic seizures) treated with a protocol of augmented psychotherapy in combination with repeated transcranial magnetic stimulation (rTMS).

INTERVENTION

We carried out a biofeedback psychotherapy protocol with rTMS (twenty sessions, two sessions per day for ten days; 1Hz, 150% of the motor threshold, twenty minute sessions, 300 pulses per session) in which the patient visualized the motor activity of her upper limbs during stimulation of the primary motor area (PMA). The evolution of neurological symptoms was assessed using the Medical Research Council Scale for Muscle Strength (MRC).

RESULTS

Symptoms were improved between the 4th and 6th days of treatment (8th and 12th sessions) with first a relief of paresis, then a secondary cascade improvement of other functional symptoms. At two months the patient no longer presented any functional neurological symptoms.

DISCUSSION & CONCLUSION

We propose several hypotheses concerning the effectiveness of this type of biofeedback protocol using rTMS. We also suggest that this type of protocol should be systematically associated with psychotherapeutic support on biographical elements for holistic management. This observation underlines the interest of potentiating cognitive-behavioral therapies using the principle of operant conditioning with the aid of brain stimulation in functional neurological disorders, and motivates the realization of future studies.

Visuomotor Transformations Are Modulated by Focused Ultrasound over Frontal Eye Field

Neuromodulation with focused ultrasound (FUS) is being widely explored as a non-invasive tool to stimulate focal brain regions because of its superior spatial resolution and coverage compared with other neuromodulation methods. The precise effects of FUS stimulation on specific regions of the brain are not yet fully understood. Here, we characterized the behavioral effects of FUS stimulation directly applied through a craniotomy over the macaque frontal eye field (FEF). In macaque monkeys making directed eye movements to perform visual search tasks with direct or arbitrary responses, focused ultrasound was applied through a craniotomy over the FEF. Saccade response times (RTs) and error rates were determined for trials without or with FUS stimulation with pulses at a peak negative pressure of either 250 or 425 kPa. Both RTs and error rates were affected by FUS. Responses toward a target located contralateral to the FUS stimulation were approximately 3 ms slower in the presence of FUS in both monkeys studied, while only one exhibited a slowing of responses for ipsilateral targets. Error rates were lower in one monkey in this study. In another search task requiring making eye movements toward a target (pro-saccades) or in the opposite direction (anti-saccades), the RT for pro-saccades increased in the presence of FUS stimulation. Our results indicate the effectiveness of FUS to modulate saccadic responses when stimulating FEF in awake, behaving non-human primates.

Bidirectional and state-dependent modulation of brain activity by transcranial focused ultrasound in non-human primates

Transcranial focused ultrasound (FUS) stimulation under MRI guidance, coupled with functional MRI (fMRI) monitoring of effects, offers a precise, noninvasive technology to dissect functional brain circuits and to modulate altered brain functional networks in neurological and psychiatric disorders. Here we show that ultrasound at moderate intensities modulated neural activity bi-directionally. Concurrent sonication of somatosensory areas 3a/3b with 250 kHz FUS suppressed the fMRI signals produced there by peripheral tactile stimulation, while at the same time eliciting fMRI activation at inter-connected, off-target brain regions. Direct FUS stimulation of the cortex resulted in different degrees of BOLD signal changes across all five off-target regions, indicating that its modulatory effects on active and resting neurons differed. This is the first demonstration of the dual suppressive and excitative modulations of FUS on a specific functional circuit and of ability of concurrent FUS and MRI to evaluate causal interactions between functional circuits with neuron-class selectivity.

Transcranial Magnetic Stimulation for the Treatment of Concussion: A Systematic Review

BACKGROUND

Post-concussive symptoms (PCSs) are common, disabling, and challenging to manage. Evolving models of concussion pathophysiology suggest evidence of brain network dysfunction that may be amenable to neuromodulation. Repetitive transcranial magnetic stimulation (rTMS) has emerged as a potential novel treatment option for PCSs.

OBJECTIVES

To systematically review rTMS trials for the treatment of symptoms following concussion/mild traumatic brain injury (mTBI).

MATERIALS AND METHODS

We conducted a systematic review of Pubmed/Medline, Embase, and PsychINFO databases were searched up to May 19, 2020. Studies were included if they were prospective rTMS treatment studies of patients with mTBI/concussion. Variables including patient demographics, study design, rTMS protocol parameters, primary outcome measures, and efficacy data were extracted and qualitatively synthesized. rTMS methodology and study quality were also evaluated.

RESULTS

Of the 342 studies identified, 11 met eligibility criteria and were included for synthesis. Forty-one percent of patients were female and age ranged from 18 to 65 (average age = 38.5 years). Post-concussive depression (seven studies) and headache (four studies) were the most commonly investigated symptoms. The majority of trials were sham-controlled with randomized control trial (RCT) designs, but all were small pilot samples (n < 30). Methodological heterogeneity and a low number of identified trials precluded quantitative meta-analysis. Regarding rTMS for post-concussive depression, positive results were found in two out of four studies with depression as a primary outcome, and all three studies that assessed depression as a secondary outcome. All four rTMS studies for post-concussive headache reported positive results.

CONCLUSIONS

rTMS for the treatment of concussion/mTBI shows promising preliminary results for post-concussive depression and headache, symptoms that otherwise have limited effective treatment options. More studies with larger sample sizes are needed to further establish potential efficacy.

Trial Of Neurostimulation In Conversion Symptoms (TONICS): a feasibility randomised controlled trial of transcranial magnetic stimulation for functional limb weakness

OBJECTIVES

Transcranial magnetic stimulation (TMS) has been used therapeutically for functional (conversion) motor symptoms but there is limited evidence for its efficacy and the optimal protocol. We examined the feasibility of a novel randomised controlled trial (RCT) protocol of TMS to treat functional limb weakness.

DESIGN

A double-blind (patient, outcome assessor) two parallel-arm, controlled RCT.

SETTING

Specialist neurology and neuropsychiatry services at a large National Health Service Foundation Trust in London, UK.

PARTICIPANTS

Patients with a diagnosis of functional limb weakness (Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition). Exclusion criteria included comorbid neurological or major psychiatric disorder, contraindications to TMS or previous TMS treatment.

INTERVENTIONS

Patients were randomised to receive either active (single-pulse TMS to primary motor cortex (M1) above resting motor threshold) or inactive treatment (single-pulse TMS to M1 below resting motor threshold). Both groups received two TMS sessions, 4 weeks apart.

OUTCOME MEASURES

We assessed recruitment, randomisation and retention rates. The primary outcome was patient-rated symptom change (Clinical Global Impression-Improvement scale, CGI-I). Secondary outcomes included clinician-rated symptom change, psychosocial functioning and disability. Outcomes were assessed at baseline, both TMS visits and at 3-month follow-up.

RESULTS

Twenty-two patients were recruited and 21 (96%) were successfully randomised (active=10; inactive=11). Nineteen (91%) patients were included at follow-up (active=9; inactive=10). Completion rates for most outcomes were good (80%-100%). Most patients were satisfied/very satisfied with the trial in both groups, although ratings were higher in the inactive arm (active=60%, inactive=92%). Adverse events were not more common for the active treatment. Treatment effect sizes for patient-rated CGI-I scores were small-moderate (Cliff's delta=-0.1-0.3, CIs-0.79 to 0.28), reflecting a more positive outcome for the active treatment (67% and 44% of active arm-rated symptoms as 'much improved' at session 2 and follow-up, respectively, vs 20% inactive group). Effect sizes for secondary outcomes were variable.

CONCLUSIONS

Our protocol is feasible. The findings suggest that supramotor threshold TMS of M1 is safe, acceptable and potentially beneficial as a treatment for functional limb weakness. A larger RCT is warranted.

TRIAL REGISTRATION NUMBER

ISRCTN51225587.

A Case of Psychogenic Myoclonus Responding to a Novel Transcranial Magnetic Stimulation Approach: Rationale, Feasibility, and Possible Neurophysiological Basis

Repetitive transcranial magnetic stimulation (rTMS) can relieve motor symptoms related to psychogenic movement disorders (PMDs), but the subtending neurophysiological basis is unclear. We report on a 50-year-old woman with a diagnosis of psychogenic myoclonus in the right lower limb, who was treated with a daily session (in the late morning/early afternoon) of 1 Hz rTMS over the left premotor cortex (PMC), five times a week for 6 weeks. Clinical data and EEG at rest were collected before and immediately and 2-month after the rTMS protocol completion. The patient reported a significant reduction of involuntary movement frequency and intensity and the related disability burden up to the follow-up. In parallel, any abnormality in terms of source current density within and connectivity between the frontal and parietal areas was reset. The short follow–up period, the lack of extensive neurophysiological measures, and the lack of control treatment represent the main limitation of the study. However, low-frequency rTMS over PMC seems a safe and promising approach for the management of psychogenic myoclonus owing to the combination of cortical neuromodulation and non-specific mechanisms suggesting cognitive-behavioral effects.

Psychosocial interventions for conversion and dissociative disorders in adults

BACKGROUND

Conversion and dissociative disorders are conditions where people experience unusual neurological symptoms or changes in awareness or identity. However, symptoms and clinical signs cannot be explained by a neurological disease or other medical condition. Instead, a psychological stressor or trauma is often present. The symptoms are real and can cause significant distress or problems with functioning in everyday life for the people experiencing them.

OBJECTIVES

To assess the beneficial and harmful effects of psychosocial interventions of conversion and dissociative disorders in adults.

SEARCH METHODS

We conducted database searches between 16 July and 16 August 2019. We searched Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and eight other databases, together with reference checking, citation searching and contact with study authors to identify additional studies.  SELECTION CRITERIA: We included all randomised controlled trials that compared psychosocial interventions for conversion and dissociative disorders with standard care, wait list or other interventions (pharmaceutical, somatic or psychosocial).  DATA COLLECTION AND ANALYSIS: We selected, quality assessed and extracted data from the identified studies. Two review authors independently performed all tasks. We used standard Cochrane methodology. For continuous data, we calculated mean differences (MD) and standardised mean differences (SMD) with 95% confidence interval (CI). For dichotomous outcomes, we calculated risk ratio (RR) with 95% CI. We assessed and downgraded the evidence according to the GRADE system for risk of bias, imprecision, indirectness, inconsistency and publication bias.

MAIN RESULTS

We included 17 studies (16 with parallel-group designs and one with a cross-over design), with 894 participants aged 18 to 80 years (female:male ratio 3:1).  The data were separated into 12 comparisons based on the different interventions and comparators. Studies were pooled into the same comparison when identical interventions and comparisons were evaluated. The certainty of the evidence was downgraded as a consequence of potential risk of bias, as many of the studies had unclear or inadequate allocation concealment. Further downgrading was performed due to imprecision, few participants and inconsistency. There were 12 comparisons for the primary outcome of reduction in physical signs. Inpatient paradoxical intention therapy compared with outpatient diazepam: inpatient paradoxical intention therapy did not reduce conversive symptoms compared with outpatient diazepam at the end of treatment (RR 1.44, 95% CI 0.91 to 2.28; 1 study, 30 participants; P = 0.12; very low-quality evidence). Inpatient treatment programme plus hypnosis compared with inpatient treatment programme: inpatient treatment programme plus hypnosis did not reduce severity of impairment compared with inpatient treatment programme at the end of treatment (MD -0.49 (negative value better), 95% CI -1.28 to 0.30; 1 study, 45 participants; P = 0.23; very low-quality evidence). Outpatient hypnosis compared with wait list: outpatient hypnosis might reduce severity of impairment compared with wait list at the end of treatment (MD 2.10 (higher value better), 95% CI 1.34 to 2.86; 1 study, 49 participants; P < 0.00001; low-quality evidence). Behavioural therapy plus routine clinical care compared with routine clinical care: behavioural therapy plus routine clinical care might reduce the number of weekly seizures compared with routine clinical care alone at the end of treatment (MD -21.40 (negative value better), 95% CI -27.88 to -14.92; 1 study, 18 participants; P < 0.00001; very low-quality evidence). Cognitive behavioural therapy (CBT) compared with standard medical care: CBT did not reduce monthly seizure frequency compared to standard medical care at end of treatment (RR 1.56, 95% CI 0.39 to 6.19; 1 study, 16 participants; P = 0.53; very low-quality evidence). CBT did not reduce physical signs compared to standard medical care at the end of treatment (MD -4.75 (negative value better), 95% CI -18.73 to 9.23; 1 study, 61 participants; P = 0.51; low-quality evidence). CBT did not reduce seizure freedom compared to standard medical care at end of treatment (RR 2.33, 95% CI 0.30 to 17.88; 1 trial, 16 participants; P = 0.41; very low-quality evidence). Psychoeducational follow-up programmes compared with treatment as usual (TAU): no study measured reduction in physical signs at end of treatment. Specialised CBT-based physiotherapy inpatient programme compared with wait list: no study measured reduction in physical signs at end of treatment. Specialised CBT-based physiotherapy outpatient intervention compared with TAU: no study measured reduction in physical signs at end of treatment. Brief psychotherapeutic intervention (psychodynamic interpersonal treatment approach) compared with standard care: brief psychotherapeutic interventions did not reduce conversion symptoms compared to standard care at end of treatment (RR 0.12, 95% CI 0.01 to 2.00; 1 study, 19 participants; P = 0.14; very low-quality evidence). CBT plus adjunctive physical activity (APA) compared with CBT alone: CBT plus APA did not reduce overall physical impacts compared to CBT alone at end of treatment (MD 5.60 (negative value better), 95% CI -15.48 to 26.68; 1 study, 21 participants; P = 0.60; very low-quality evidence). Hypnosis compared to diazepam: hypnosis did not reduce symptoms compared to diazepam at end of treatment (RR 0.69, 95% CI 0.39 to 1.24; 1 study, 40 participants; P = 0.22; very low-quality evidence). Outpatient motivational interviewing (MI) and mindfulness-based psychotherapy compared with psychotherapy alone: psychotherapy preceded by MI might decrease seizure frequency compared with psychotherapy alone at end of treatment (MD 41.40 (negative value better), 95% CI 4.92 to 77.88; 1 study, 54 participants; P = 0.03; very low-quality evidence). The effect on the secondary outcomes was reported in 16/17  studies. None of the studies reported results on adverse effects. In the studies reporting on level of functioning and quality of life at end of treatment the effects ranged from small to no effect.

AUTHORS' CONCLUSIONS

The results of the meta-analysis and reporting of single studies suggest there is lack of evidence regarding the effects of any psychosocial intervention on conversion and dissociative disorders in adults. It is not possible to draw any conclusions about potential benefits or harms from the included studies.

Maximizing placebo response in neurological clinical practice

The placebo effect is a widely recognized phenomenon in clinical research, with a negative perception that it could hide the "true" drug effect. In clinical care its positive potential to increase known drug effects has been neglected for too long. The placebo and nocebo responses have been described in many neurologic disorders such as Parkinson's, Huntington's and Alzheimer's diseases, restless leg syndrome, tics, essential tremor, dystonia, functional movement disorders, neuropathic pain, headaches, migraine, amyotrophic lateral sclerosis, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy, multiple sclerosis and epilepsy. Knowledge regarding placebo mechanisms and their consequences on clinical outcome have greatly improved over the last two decades. This evolution has led to reconsiderations of the importance of placebo response in the clinic and has given several clues on how to improve it in daily practice. In this chapter, we first illustrate "why," e.g. the reasons (relevance to clinical practice, help in differential diagnosis/treatment of psychogenic movements, clinical impact, proven neurobiological grounds, health economic potential), and "how," e.g. the means (increase patients' knowledge, increase learning, improve patient-doctor relationship, increase Hawthorne effect, increase positive/decrease negative expectations (the Rosenthal effect), personalize placebo response), the placebo should be maximized (and nocebo avoided) in neurological clinical practice. Future studies regarding more specific neurobiological mechanisms will allow a finer tuning of placebo response in clinical practice. The use of placebo in clinical practice raises ethical issues, and a recent expert consensus regarding placebo use in the clinic is a first step to future guidelines necessary to this field.

Triggers and Clinical Presentations of Functional Neurological Disorders: Lessons from World War 1

INTRODUCTION

The psychological contribution to functional neurological and somatic symptom disorders is a major topic in current medical debate.

OBJECTIVE

For an understanding of the processes leading to functional somatic symptoms, it is paramount to explore their relationship with stress and life events and to elucidate the contribution of cultural factors.

METHODS

A total of 937 case records of civilian and military patients with functional somatic disorders treated in London during World War 1 were analysed. Group differences in symptom profiles and contemporaneous diagnoses were tested with χ2 tests.

RESULTS

Paralyses and speech disturbances were significantly more common in soldiers (43.3 and 17.2% of cases) than in civilian male (28.1 and 6.5%) and female patients (32.4 and 7.5%), whereas female patients had the highest rates of pain (48.6%) and somatic symptoms (67%). Triggers were identified in around two-thirds of cases and included accidents, physical illness, and work stress, in addition to the combat experience of the soldier patients. The nature of the trigger influenced symptom expression, with acute (combat and noncombat) events being particularly prone to trigger loss of motor function. Symptom profiles showed a great deal of multi-morbidity and overlap, although some symptom clusters were more (motor and speech disturbance) or less common (pain and loss of energy) in soldiers than civilians. Triggering life events in civilians were similar to those reported by patients with somatic symptom disorders today, with an important role of physical factors. Patterns of multi-morbidity and symptom clusters also resembled those of modern cohorts.

CONCLUSIONS

Analysis of historical records, illness trajectories, and treatments can enhance the understanding of the presentation, mechanisms, and course of functional neurological and related disorders and their consistency over time.

Cortical Inhibitory Imbalance in Functional Paralysis

BACKGROUND

Functional neurological disorders are characterized by neurological symptoms that have no identifiable pathology and little is known about their underlying pathophysiology.

OBJECTIVES

To analyze motor cortex excitability and intracortical inhibitory and excitatory circuits' imbalance in patients with flaccid functional weakness.

METHODS

Twenty-one consecutive patients with acute onset of flaccid functional weakness were recruited. Single and paired-pulse transcranial magnetic stimulation (TMS) protocols were used to analyze resting motor thresholds (RMT) and intracortical inhibitory (short interval intracortical inhibition - SICI) and excitatory (intracortical facilitation - ICF) circuits' imbalance between the affected and non-affected motor cortices.

RESULTS

We observed a significant increase in RMT and SICI in the affected motor cortex (p < 0.001), but not for ICF, compared to the contralateral unaffected side.

CONCLUSION

This study extends current knowledge of functional weakness, arguing for a specific central nervous system abnormality which may be involved in the symptoms' pathophysiology.

Transcranial Magnetic Stimulation for the Treatment of Pediatric Neurological Disorders

PURPOSE OF REVIEW

Repetitive transcranial magnetic stimulation (rTMS) is a form of noninvasive brain stimulation that is used for the treatment of migraine and major depression in adults and is now being evaluated for use in other disorders. The purpose of this review is to summarize the physiology underlying TMS, the safety and tolerability in pediatric patients, and the evidence for TMS efficacy in the treatment of pediatric neurologic disorders.

RECENT FINDINGS

Studies investigating rTMS for adolescent depression, hemiparesis due to pediatric stroke, autism, and tics/Tourette syndrome have demonstrated some therapeutic benefit. rTMS has been insufficiently studied for migraine in children despite benefits demonstrated for adult migraine. Evidence for rTMS in childhood epilepsy and ADHD remains mixed. Repetitive transcranial magnetic stimulation is emerging as a safe, tolerable, and potentially effective therapeutic strategy in a number of pediatric neurological disorders, though high-quality, randomized controlled trials are needed. Ongoing studies should focus on optimization of treatment protocols, development of biomarkers to identify children who will benefit from the technique, and identification of the most appropriate indicators of response.

Selective distant electrostimulation by synchronized bipolar nanosecond pulses

A unique aspect of electrostimulation (ES) with nanosecond electric pulses (nsEP) is the inhibition of effects when the polarity is reversed. This bipolar cancellation feature makes bipolar nsEP less efficient at biostimulation than unipolar nsEP. We propose to minimize stimulation near pulse-delivering electrodes by applying bipolar nsEP, whereas the superposition of two phase-shifted bipolar nsEP from two independent sources yields a biologically-effective unipolar pulse remotely. This is accomplished by electrical compensation of all nsEP phases except the first one, resulting in the restoration of stimulation efficiency due to cancellation of bipolar cancellation (CANCAN-ES). We experimentally proved the CANCAN-ES paradigm by measuring YO-PRO-1 dye uptake in CHO-K1 cells which were permeabilized by multiphasic nsEP (600 ns per phase) from two generators; these nsEP were synchronized either to overlap into a unipolar pulse remotely from electrodes (CANCAN), or not to overlap (control). Enhancement of YO-PRO-1 entry due to CANCAN was observed in all sets of experiments and reached ~3-fold in the center of the gap between electrodes, exactly where the unipolar pulse was formed, and equaled the degree of bipolar cancellation. CANCAN-ES is promising for non-invasive deep tissue stimulation, either alone or combined with other remote stimulation techniques to improve targeting.

Pathogenesis and pathophysiology of functional (psychogenic) movement disorders

Functional movement disorders (FMDs), known over time as "hysteria", "dissociative", "conversion", "somatoform", "non-organic" and "psychogenic" disorders, are characterized by having a voluntary quality, being modifiable by attention and distraction but perceived by the patient as involuntary. Although a high prevalence of depression and anxiety is observed in these patients, a definitive role of psychiatric disorders in FMDs has not been proven, and many patients do not endorse such manifestations. Stressful events, social influences and minor trauma may precede the onset of FMDs, but their pathogenic mechanisms are unclear. Patients with FMDs have several abnormalities in their neurobiology including strengthened connectivity between the limbic and motor networks. Additionally, there is altered top-down regulation of motor activities and increased activation of areas implicated in self-awareness, self-monitoring, and active motor inhibition such as the cingulate and insular cortex. Decreased activation of the supplementary motor area (SMA) and pre-SMA, implicated in motor control and preparation, is another finding. The sense of agency defined as the feeling of controlling external events through one's own action also seems to be impaired in individuals with FMDs. Correlating with this is a loss of intentional binding, a subjective time compression between intentional action and its sensory consequences. Organic and functional dystonia may be difficult to differentiate since they share diverse neurophysiological features including decreased cortical inhibition, and similar local field potentials in the globus pallidus and thalamus; although increased cortical plasticity is observed only in patients with organic dystonia. Advances in the pathogenesis and pathophysiology of FMDs may be helpful to understand the nature of these disorders and plan further treatment strategies.

Functional neuroimaging in patients presenting with somatoform disorders: A model for investigating persisting symptoms after tick bites and post-treatment Lyme disease syndrome?

Approximately 10% of patients presenting with Lyme disease experience fatigue, musculoskeletal pain, concentration disorders, or short-term memory deficits in the six months following treatment. This entity has been defined as post-Lyme disease syndrome or post-treatment Lyme disease syndrome. The pathophysiology of this syndrome is unknown, but neither persistence of the bacterium nor effectiveness of antibiotics are currently reported in the literature. The French High Council for Public Health (French acronym HCSP) has recently defined a new entity called "persistent polymorphic symptoms after a tick bite" allowing for designing studies to better understand these subjective presentations, for which objective biomarkers are currently lacking. This entity encompasses patients experiencing fatigue and generalized pain in the months following a tick bite and can be associated with several subjective symptoms with major impact on the quality of life. In the field of somatoform disorders, this article reviews functional neuroimaging studies in patients presenting with subjective complaints and discusses potential clinical implications for persisting symptoms after tick bites and post-treatment Lyme disease syndrome.

Neuromodulation of sensory networks in monkey brain by focused ultrasound with MRI guidance and detection

Focused ultrasound (FUS) has gained recognition as a technique for non-invasive neuromodulation with high spatial precision and the ability to both excite and inhibit neural activity. Here we demonstrate that MRI-guided FUS is capable of exciting precise targets within areas 3a/3b in the monkey brain, causing downstream activations in off-target somatosensory and associated brain regions which are simultaneously detected by functional MRI. The similarity between natural tactile stimulation-and FUS- evoked fMRI activation patterns suggests that FUS likely can excite populations of neurons and produce associated spiking activities that may be subsequently transmitted to other functionally related touch regions. The across-region differences in fMRI signal changes relative to area 3a/3b between tactile and FUS conditions also indicate that FUS modulated the tactile network differently. The significantly faster rising (>1 sec) fMRI signals elicited by direct FUS stimulation at the targeted cortical region suggest that a different neural hemodynamic coupling mechanism may be involved in generating fMRI signals. This is the first demonstration of imaging neural excitation effects of FUS with BOLD fMRI on a specific functional circuit in non-human primates.

Conversion Disorder, Functional Neurological Symptom Disorder, and Chronic Pain: Comorbidity, Assessment, and Treatment

PURPOSE OF REVIEW

This paper examines the overlap of conversion disorder with chronic pain conditions, describes ways to assess for conversion disorder, and provides an overview of evidence-based treatments for conversion disorder and chronic pain, with a focus on conversion symptoms.

RECENT FINDINGS

Conversion disorder is a significant problem that warrants further study, given that there are not many well-established guidelines. Accurate and timely assessment should help move treatment in a more fruitful direction and avoid unnecessary medical interventions. Advances in neuroimaging may also help further our understanding of conversion disorder. Creating a supportive environment and a collaborative treatment relationship and improving understanding of conversion symptoms appear to help individuals diagnosed with conversion disorder engage in appropriate treatments. Novel uses of earlier treatments, such as hypnosis and psychodynamic approaches, could potentially be beneficial and require a more vigorous and systematic study. There are treatments that produce significant improvements in functioning and reduction of physical symptoms from conversion disorder even for very severe cases. Hypnotherapy, cognitive behavioral therapy, and inpatient multidisciplinary treatment with intensive physiotherapy for severe cases have the most evidence to support reduction of symptoms. Components of treatment for conversion disorder overlap with treatments for chronic pain and can be used together to produce therapeutic effects for both conditions. Treatment needs to be tailored for each individual's specific symptoms.

Effectiveness of repetitive transcranial magnetic stimulation (rTMS) after acute stroke: A one-year longitudinal randomized trial

AIMS

To evaluate the effectiveness of repetitive transcranial magnetic stimulation (rTMS) on motor recovery after stroke using a prospective, double-blind, randomized, sham-controlled study.

METHODS

Patients with unilateral subcortical infarction in the middle cerebral artery territory within 1 week after onset were enrolled. The patients were randomly divided into an rTMS treatment group and a sham group. We performed high-frequency rTMS or sham rTMS on the two groups. Motor functional scores were assessed pre- and post-rTMS/sham rTMS and at 1 month, 3 months, 6 months, and 1 year after stroke onset. The scores included the National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI), Fugl-Meyer Assessment Upper Limb/Lower Limb (FMA-UL/LL), modified Rank Score (mRS), and the resting motor threshold (RMT) of the hemiplegic limb.

RESULTS

At baseline, no significant differences were found between the two groups for motor functional scores. On the second day after rTMS treatment, score improvements of the NIHSS, BI, FMA-UL in the real treatment group were more significant than those in the sham group. In addition, similar results were obtained at 1 month. However, at 3 months, 6 months, and 1 year after onset, no significant differences in improvement were observed between the two groups, except for the FMA-UL score improvement.

CONCLUSION

rTMS facilitates motor recovery of acute stroke patients, and the effect can last to 1 month, except the function improvement on upper extremities could last for 1 year. A single course of rTMS in the acute stage may induce the improvement of upper extremities function lasted for 1 year.

Impact of Transcranial Magnetic Stimulation on Functional Movement Disorders: Cortical Modulation or a Behavioral Effect?

Introduction

Recent studies suggest that repeated transcranial magnetic stimulation (TMS) improves functional movement disorders (FMDs), but the underlying mechanisms are unclear. The objective was to determine whether the beneficial action of TMS in patients with FMDs is due to cortical neuromodulation or rather to a cognitive-behavioral effect.

Method

Consecutive patients with FMDs underwent repeated low-frequency (0.25 Hz) magnetic stimulation over the cortex contralateral to the symptoms or over the spinal roots [root magnetic stimulation (RMS)] homolateral to the symptoms. The patients were randomized into two groups: group 1 received RMS on day 1 and TMS on day 2, while group 2 received the same treatments in reverse order. We blindly assessed the severity of movement disorders before and after each stimulation session.

Results

We studied 33 patients with FMDs (dystonia, tremor, myoclonus, Parkinsonism, or stereotypies). The median symptom duration was 2.9 years. The magnetic stimulation sessions led to a significant improvement (>50%) in 22 patients (66%). We found no difference between TMS and RMS.

Conclusion

We suggest that the therapeutic benefit of TMS in patients with FMDs is due more to a cognitive-behavioral effect than to cortical neuromodulation.

Transcranial magnetic stimulation as a treatment for functional (psychogenic) upper limb weakness

OBJECTIVE

There has been a recent resurgence of interest in physical treatments for functional motor disorders (FMD) including Transcranial Magnetic Stimulation (TMS). This pilot study aimed to test the effectiveness of a single session of motor cortex TMS as a treatment for functional upper limb weakness.

METHODS

Ten subjects with a diagnosis of functional upper limb weakness were randomised to immediate (n=7) or delayed (3months) (n=3) TMS treatment. Median age was 35 (range 23-52) and median symptom duration was 2.3years (range 5months - 20years). 46-70 single pulses were applied to the motor cortex at 120-150% motor threshold. We used a verbal protocol designed to standardized the effects of suggestion. Primary outcome measures were self-reported symptom severity, grip strength and tapping frequency immediately after treatment, and symptom severity and disability (SF-12 and Modified Rankin Scale (MRS)) after 3months.

RESULTS

There was a small significant reduction in symptom severity immediately after treatment, but no improvement in grip strength or tapping frequency and no change in symptom severity, SF-12 or MRS 3months after treatment. Small numbers precluded comparison of immediate treatment with delayed treatment. Four of eight subjects responding to three-month follow-up reported late-onset adverse effects.

CONCLUSION

This pilot study suggests limited benefits for TMS as a one-off non-neuromodulatory treatment for stable chronic outpatients. TMS may still have a role alongside more intensive multidisciplinary therapy input, or in patients with severe deficits where the possibility of normal movement can be hard to demonstrate.

TRIAL REGISTRATION

NCT02102906.

Noninvasive Electric Current Induction for Low-Frequency Tissue Conductivity Reconstruction: Is It Feasible With a TMS-MRI Setup?

Noninvasive quantification of subject-specific low-frequency brain tissue conductivity ( σLF ) will be valuable in different fields, for example, neuroscience. Magnetic resonance (MR)-electrical impedance tomography allows measurements of σLF . However, the required high level of direct current injection leads to an undesirable pain sensation. Following the same principles, but avoiding pain sensation, we evaluate the feasibility of inductively inducing currents using a transcranial magnetic stimulation (TMS) device and recording the magnetic field variations arising from the induced tissue eddy currents using a standard 3 T MR scanner. Using simulations, we characterize the strength of the incident TMS magnetic field arising from the current running in the TMS coil, the strength of the induced magnetic field arising from the induced currents in tissues by TMS pulses, and the MR phase accuracy required to measure this latter magnetic field containing information about σLF . Then, using TMS-MRI measurements, we evaluate the achievable phase accuracy for a typical TMS-MRI setup. From measurements and simulations, it is crucial to discriminate the incident from the induced magnetic field. The incident TMS magnetic field range is ±10^-4 T, measurable with standard MR scanners. In contrast, the induced TMS magnetic field is much weaker (±10^-8 T), leading to an MR phase contribution of ∼10^-4 rad. This phase range is too small to be measured, as the phase accuracy for TMS-MRI experiments is ∼10^-2 rads. Thus, although highly attractive, noninvasive measurements of the induced TMS magnetic field, and therefore estimations of σLF , are experimentally not feasible.

Non-Invasive Brain Stimulation in Conversion (Functional) Weakness and Paralysis: A Systematic Review and Future Perspectives

Conversion (functional) limb weakness or paralysis (FW) can be a debilitating condition, and often causes significant distress or impairment in social, occupational, or other important areas of functioning. Most treatment concepts are multi-disciplinary, containing a behavioral approach combined with a motor learning program. Non-invasive brain stimulation (NIBS) methods, such as electroconvulsive therapy (ECT), and transcranial magnetic stimulation (TMS) have been used in the past few decades to treat FW. In order to identify all published studies that used NIBS methods such as ECT, TMS and transcranial direct current stimulation (tDCS) for treating FW patients a systematic review of the literature was conducted in PubMed and Web of Science. In a second step, narratives were used to retrospectively determine nominal CGI-I (Clinical Global Impression scale–Improvement) scores to describe approximate changes of FW symptoms. We identified two articles (case reports) with ECT used for treatment of FW, five with TMS with a total of 86 patients, and none with tDCS. In 75 out of 86 patients treated with repetitive (r)TMS a nominal CGI-I score could be estimated, showing a satisfactory short-term improvement. Fifty-four out of seventy-five identified patients (72%) had a CGI-I score of 1 (very much improved), 13 (17%) a score of 2 (much improved), 5 (7%) a score of 3 (minimally improved), and 3 (5%) remained unchanged (CGI-I = 4). In no case did patients worsen after rTMS treatment, and no severe adverse effects were reported. At follow-up, symptom improvement was not quantifiable in terms of CGI-I for the majority of the cases. Patients treated with ECT showed a satisfactory short-term response (CGI-I = 2), but deterioration of FW symptoms at follow-up. Despite the predominantly positive results presented in the identified studies and satisfactory levels of efficacy measured with retrospectively calculated nominal CGI-I scores, any assumption of a beneficial effect of NIBS in FW has to be seen with caution, as only few articles could be retrieved and their quality was mostly poor. This article elucidates how NIBS might help in FW and gives recommendations for future study designs using NIBS in this condition.

Cranial functional (psychogenic) movement disorders

Functional (psychogenic) neurological symptoms are frequently encountered in neurological practice. Cranial movement disorders--affecting the eyes, face, jaw, tongue, or palate--are an under-recognised feature of patients with functional symptoms. They can present in isolation or in the context of other functional symptoms; in particular, for functional eye movements, positive clinical signs such as convergence spasms can be triggered by the clinical examination. Although the specialty of functional neurological disorders has expanded, appreciation of cranial functional movement disorders is still insufficient. Identification of the positive features of cranial functional movement disorders such as convergence and unilateral platysmal spasm might lend diagnostic weight to a suspected functional neurological disorder. Understanding of the differential diagnosis, which is broad and includes many organic causes (eg, stroke), is essential to make an early and accurate diagnosis to prevent complications and initiate appropriate management. Increased understanding of these disorders is also crucial to drive clinical trials and studies of individually tailored therapies.

Transcranial magnetic stimulation and sedation as treatment for functional neurologic disorders

Functional neurologic disorder (FND), also known as conversion disorder, is common and often associated with a poor prognosis. It has been relatively neglected by research and as such there is a conspicuous lack of evidence-based treatments. Physical and psychologic therapies are the main treatment modalities, over and above reassurance and sensitive explanation of the diagnosis. However there are two other historic treatments that have seen a recent resurgence of interest and use. The first is electric stimulation, which was initially pioneered with direct stimulation of nerves but now used indirectly (and therefore noninvasively) in the form of transcranial magnetic stimulation (TMS). The second is (therapeutic) sedation, previously known as "abreaction," where it was mostly used in the context of psychologic investigation and treatment, but now increasingly advocated during rehabilitation as a way to therapeutically demonstrate reversibility of symptoms. This chapter introduces the background of these treatment modalities, their evolution into their current applications before critically evaluating their current evidence base and exploring possible mechanisms of action. It also tentatively suggests when they should be considered in current practice and briefly considers their future potential. In summary there is encouraging preliminary evidence to suggest that both TMS and sedation may be effective treatments for FNDs.

Neurophysiologic studies of functional neurologic disorders

Functional neurologic disorders are largely genuine and represent conversion disorders, where the dysfunction is unconscious, but there are some that are factitious, where the abnormality is feigned and conscious. Malingering, which can have the same manifestations, is similarly feigned, but not considered a genuine disease. There are no good methods for differentiating these three entities at the present time. Physiologic studies of functional weakness and sensory loss reveal normal functioning of primary motor and sensory cortex, but abnormalities of premotor cortex and association cortices. This suggests a top-down influence creating the dysfunction. Studies of functional tremor and myoclonus show that these disorders utilize normal voluntary motor structures to produce the involuntary movements, again suggesting a higher-level abnormality. Agency is abnormal and studies shows that dysfunction of the temporoparietal junction may be a correlate. The limbic system is overactive and might initiate involuntary movements, but the mechanism for this is not known. The limbic system would then be the source of top-down dysfunction. It can be speculated that the involuntary movements are involuntary due to lack of proper feedforward signaling.

Functional dystonia

Although currently lacking a sensitive and specific electrophysiologic battery test, functional (psychogenic) dystonia can sometimes be diagnosed with clinically definite certainty using available criteria. Certain regional phenotypes have been recognized as distinctive, such as unilateral lip and jaw deviation, laterocollis with ipsilateral shoulder elevation and contralateral shoulder depression, fixed wrist and finger flexion with relative sparing of the thumb and index fingers, and fixed foot plantar flexion and inversion. The pathophysiologic abnormalities in functional dystonia overlap substantially with those of organic dystonia, with similar impairments in cortical and spinal inhibition and somatosensory processing, but with emerging data suggesting abnormalities in regional blood flow and activation patterns on positron emission tomography and functional magnetic resonance imaging, respectively. Management of functional dystonia begins with compassionate and assertive debriefing of the diagnosis to ensure full acceptance by the patient, a critical step in enhancing the likelihood of success with physical rehabilitation, and psychodynamic or cognitive therapy. Physical therapy, with or without cognitive behavioral therapy, appears to be of benefit but has not yet been examined in a controlled fashion. While the prognosis remains grim for a substantial majority of patients, partly stemming from restricted mobility, delayed diagnosis, and inappropriate pharmacotherapy, early recognition and initiation of therapy stand to minimize iatrogenic harm and unnecessary laboratory investigations, and potentially reduce the long-term neurologic disability.

Physiotherapy for functional motor disorders: a consensus recommendation

BACKGROUND

Patients with functional motor disorder (FMD) including weakness and paralysis are commonly referred to physiotherapists. There is growing evidence that physiotherapy is an effective treatment, but the existing literature has limited explanations of what physiotherapy should consist of and there are insufficient data to produce evidence-based guidelines. We aim to address this issue by presenting recommendations for physiotherapy treatment.

METHODS

A meeting was held between physiotherapists, neurologists and neuropsychiatrists, all with extensive experience in treating FMD. A set of consensus recommendations were produced based on existing evidence and experience.

RESULTS

We recommend that physiotherapy treatment is based on a biopsychosocial aetiological framework. Treatment should address illness beliefs, self-directed attention and abnormal habitual movement patterns through a process of education, movement retraining and self-management strategies within a positive and non-judgemental context. We provide specific examples of these strategies for different symptoms.

CONCLUSIONS

Physiotherapy has a key role in the multidisciplinary management of patients with FMD. There appear to be specific physiotherapy techniques which are useful in FMD and which are amenable to and require prospective evaluation. The processes involved in referral, treatment and discharge from physiotherapy should be considered carefully as a part of a treatment package.

Efficacy of brief interdisciplinary psychotherapeutic intervention for motor conversion disorder and nonepileptic attacks

OBJECTIVE

The objective was to compare a brief interdisciplinary psychotherapeutic intervention to standard care as treatments for patients recently diagnosed with severe motor conversion disorder or nonepileptic attacks.

METHODS

This randomized controlled trial of 23 consecutive patients compared (a) an interdisciplinary psychotherapeutic intervention group receiving four to six sessions by a consultation liaison psychiatrist, the first and last sessions adding a neurological consultation and a joint psychiatric and neurological consultation, and (b) a standard care group. After intervention, patients were assessed at 2, 6 and 12 months with the Somatoform Dissociation Questionnaire (SDQ-20), Clinical Global Impression scale, Rankin scale, use of medical care, global mental health [Montgomery and Asberg Depression Rating Scale, Beck Depression Inventory, mental health component of Short Form (SF)-36] and quality of life (SF-36). We calculated linear mixed models.

RESULTS

Our intervention brought a statistically significant improvement of physical symptoms [as measured by the SDQ-20 (P<.02) and the Clinical Global Impression scale (P=.02)] and psychological symptoms [better scores on the mental health component of the SF-36 (P<.05) and on the Beck Depression Inventory (P<.05)] and a reduction in new hospital stays after intervention (P<.05).

CONCLUSION

A brief psychotherapeutic intervention taking advantage of a close collaboration with neurology consultants in the setting of consultation liaison psychiatry appears effective.

An update on functional (psychogenic) tremor

Functional tremor accounts for at least 50% of patients with functional movement disorders. The diagnostic work-up of these patients can be challenging. It is a multistep process based on patients’ history and clinical criteria finally providing a ‘positive’ diagnosis. Variability of the tremor over the disease course and during clinical examination is characteristic. Patients often show increased attention toward the tremulous body part and distractability of the tremor once attention is drawn away. Sometimes distractability becomes obvious during history taking or neurological examination, in others certain distraction tasks are needed. If uncertainty remains, ancillary investigations such as electrophysiological tests may be helpful. Recent studies suggested that a loss of sense of control of ones actions may help to explain why patients with functional tremor report that they do not experience the abnormal movement as voluntary. Treatment has to be placed in a multidisciplinary team involving neurologists, psychiatrists, physiotherapists and psychologists.