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Contains fulltext : 252111.pdf (Publisher’s version ) (Open Access) The various forms of tremor are now classified in two axes: clinical characteristics (axis 1) and etiology (axis 2). Electrophysiology is an extension of the clinical exam. Electrophysiologic tests are diagnostic of physiologic tremor, primary orthostatic tremor, and functional tremor, but they are valuable in the clinical characterization of all forms of tremor. Electrophysiology will likely play an increasing role in axis 1 tremor classification because many features of tremor are not reliably assessed by clinical examination alone. In particular, electrophysiology may be needed to distinguish tremor from tremor mimics, assess tremor frequency, assess tremor rhythmicity or regularity, distinguish mechanical-reflex oscillation from central neurogenic oscillation, determine if tremors in different body parts, muscles, or brain regions are strongly correlated, document tremor suppression or entrainment by voluntary movements of contralateral body parts, and document the effects of voluntary movement on rest tremor. In addition, electrophysiologic brain mapping has been crucial in our understanding of tremor pathophysiology. The electrophysiologic methods of tremor analysis are reviewed in the context of physiologic tremor and pathologic tremors, with a focus on clinical characterization and pathophysiology. Electrophysiology is instrumental in elucidating tremor mechanisms, and the pathophysiology of the different forms of tremor is summarized in this review.

ZusammenfassungMehr als 20% der Patienten mit idiopathischem Parkinson-Syndrom (IPS) entwickeln Psychosen. Am häufigsten sind visuelle Halluzinationen. Bei der Entwicklung der Psychosen scheinen die Pathogenese der Parkinson-Erkrankung sowie ihre Dauer ebenso eine Rolle zu spielen wie modulierende Effekte der dopaminergen Therapie. Beim Therapiemanagement steht neben allgemeinen Maßnahmen zunächst die Anpassung der dopaminergen Therapie im Vordergrund. Dies kann zu einer Gratwanderung werden zwischen Besserung der Halluzinationen und Verschlechterung der Motorik. Bei unzureichendem Erfolg kann eine antipsychotische Therapie notwendig werden – dabei ist die Auswahl auf sehr wenige Antipsychotika beschränkt, um nicht ernsthafte motorische Verschlechterungen zu riskieren. In der vorliegenden Arbeit wurden basierend auf dem aktuellen Stand der Literatur sowie empirischen Experten-basierten Erfahrungen aus dem klinischen Alltag relevante Aspekte zu Halluzinationen bei IPS-Patienten in der Praxis zusammengefasst und Empfehlungen zum Therapiemanagement erarbeitet.

OBJECTIVE: We sought to evaluate demographic, clinical, and habits/occupational variables between phenotypic extremes in Parkinson's disease (PD). METHODS: Databases from nine movement disorders centers across seven countries were retrospectively searched for subjects meeting criteria for very slowly progressive, benign, PD (bPD) and rapidly progressive, malignant, PD (mPD). bPD was defined as Hoehn and Yahr (H&Y) stage ≤ 3, normal cognitive function, and Schwab and England (S&E) score ≥ 70 after ≥ 20 years of PD (≥ 10 years if older than 60 at PD onset); mPD as H&Y > 3, S&E score 68-year-old). CONCLUSIONS: Phenotypic PD extremes showed distinct demographic, clinical, and habits/occupational factors. Motor complications may be conceived as markers of therapeutic success given their attenuating effects on the odds of mPD.

Essential tremor (ET) is a progressive movement disorder whose pathophysiology is not fully understood. Current evidence supports the view that the cerebellum is critically involved in the genesis of the tremor in ET. However, it is still unknown whether cerebellar dysfunction affects not only the control of current movements but also the prediction of future movements through dynamic adaptation toward a changed environment. Here, we tested the capacity of 28 patients with ET to adapt in a visuomotor adaptation task known to depend on intact cerebellar function. We found specific impairments in that task compared to age-matched healthy controls. Adaptation to the visual perturbation was disrupted in ET patients, while de-adaptation, the phase after abrupt removal of the perturbation, developed similarly to control subjects. Baseline tremor-independent motor performance was as well similar to healthy controls, indicating that adaptation deficits in ET patients were not rooted in an inability to perform goal-directed movements. There was no association between clinical severity scores of ET and early visuomotor adaptation abilities. These results provide further evidence that the cerebellum is dysfunctional in ET.

Patients with idiopathic Parkinson's disease develop symptoms of the hallucination-psychosis spectrum in more than 20%. Most common are visual hallucinations. The pathogenesis of hallucinations mainly depends on disease duration, the distribution and extent of alpha-synuclein pathology, and modulating effects of the dopaminergic therapy. When managing PD hallucinations both anti-delirogenic actions and medication management are important. However, decrease in dopaminergic medication may lead to critical worsening of akinesia. If appropriate neuroleptic medication - essentially quetiapin or clozapin - can be considered. Instead, anti-dopaminergic neuroleptics should not be used owing to their pro-akinetic side-effects. Here, we provide therapy recommendations to manage PD hallucinations based on an up-to-date targeted review of the literature and expert-based empirical evidence.Mehr als 20% der Patienten mit idiopathischem Parkinson-Syndrom (IPS) entwickeln Psychosen. Am häufigsten sind visuelle Halluzinationen. Bei der Entwicklung der Psychosen scheinen die Pathogenese der Parkinson-Erkrankung sowie ihre Dauer ebenso eine Rolle zu spielen wie modulierende Effekte der dopaminergen Therapie. Beim Therapiemanagement steht neben allgemeinen Maßnahmen zunächst die Anpassung der dopaminergen Therapie im Vordergrund. Dies kann zu einer Gratwanderung werden zwischen Besserung der Halluzinationen und Verschlechterung der Motorik. Bei unzureichendem Erfolg kann eine antipsychotische Therapie notwendig werden – dabei ist die Auswahl auf sehr wenige Antipsychotika beschränkt, um nicht ernsthafte motorische Verschlechterungen zu riskieren. In der vorliegenden Arbeit wurden basierend auf dem aktuellen Stand der Literatur sowie empirischen Experten-basierten Erfahrungen aus dem klinischen Alltag relevante Aspekte zu Halluzinationen bei IPS-Patienten in der Praxis zusammengefasst und Empfehlungen zum Therapiemanagement erarbeitet.

Background: Essential tremor (ET) occurs with steeply increasing prevalence in the elderly, and apart from disease duration, age is independently associated with an increase of tremor amplitude and a decrease of frequency. White matter hyperintensities (WMHs) are a common finding in the elderly, and their role in the pathophysiology of ET is unknown. The aims of this study were to examine whether ET patients differ in their total or region-specific WMH volumes from healthy controls and to determine the impact of WMH on tremor characteristics.Methods: A total of 47 elderly ET patients with a mean age of 72 years and 39 age-matched healthy controls underwent a thorough clinical assessment and 3T MRI. Total WMH volumes were derived from T2-weighted fluid-attenuated inversion recovery (FLAIR) MR images. Additionally, region of interest-based WMH volumes for the Johns Hopkins University (JHU) white matter tracts and labels were calculated, and WMHs were assessed semiquantitatively using the Fazekas scale.Results: Essential tremor patients and healthy controls did not differ in their total or tract-specific WMH volumes or Fazekas scores. However, WMH volume was significantly positively correlated with tremor severity on the TETRAS scale, and there was a significant negative correlation with the mean accelerometric tremor frequency. In a multiple linear regression model including disease duration, age, and age-adjusted total WMH volume, only the WMH volume significantly predicted tremor severity, while age and disease duration were not significant.Conclusion: We found evidence for a direct association between WMH volume and tremor severity. If confirmed by larger studies, our findings could explain the well-known relation between age and tremor severity.

Background The advent of therapeutic strategies designed to modify the disease course in Parkinson’s disease has raised great expectations in the currently conducted clinical trials. However, we see ethical challenges in the cooperation of industry and clinical partners, specifically evident in the way recruitment is performed. We here discuss the different positions and challenges of all involved to set the stage for a study and recruitment culture taking into account the expectations of all: (i) patients and their caregivers, ready to take the considerable burden of clinical trials in hope for the development of disease-modifying treatments; (ii) physicians and study nurses, obligated to the patients’ well-being and benefit who accompany and supervise patients closely as basis for the performance of elaborate clinical trials (iii) industrial partners, investing years of efforts and finances to develop new treatments. Conclusions We conclude that the current competitive race for enrollment in clinical studies in PD is challenging the primary goal to ensure patients’ benefit and formulate requests to the industrial partners to encounter these concerns.

BACKGROUND Systematic perceptual distortions of tactile space have been documented in healthy adults. In isolated focal dystonia impaired spatial somatosensory processing is suggested to be a central pathophysiological finding, but the structure of tactile space for different body parts has not been previously explored. OBJECTIVES The objective of this study was to assess tactile space organization with a novel behavioral paradigm of tactile distance perception in patients with isolated focal dystonia and controls. METHODS Three groups of isolated focal dystonia patients (cervical dystonia, blepharospasm/Meige syndrome, focal hand dystonia) and controls estimated perceived distances between 2 touches across 8 orientations on the back of both hands and the forehead. RESULTS Stimulus size judgments differed significantly across orientations in all groups replicating distortions of tactile space known for healthy individuals. There were no differences between groups in the behavioral parameters we assessed on the hands and forehead. CONCLUSIONS Tactile space organization is comparable between patients with isolated focal dystonia and healthy controls in dystonic and unaffected body parts. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Das Restless Legs Syndrom (RLS) fuhrt zu einer erheblichen Beeintrachtigung des Schlafs, und ist in bis zu 80 % der Falle mit einer signifikanten Tagesmudigkeit verbunden. Neben familiaren und genetischen Ursachen gibt es symptomatische Formen. Zugrunde liegt eine Storung des Eisen- und Dopaminstoffwechsels. Therapeutisch sind neben Levodopa auch Dopaminrezeptoragonisten zugelassen.

Writer's cramp (WC) is a focal task-specific dystonia characterized by sustained or intermittent muscle contractions while writing, particularly with the dominant hand. Since structural lesions rarely cause WC, it has been assumed that the disease might be caused by a functional maladaptation within the sensory-motor system. Therefore, our objective was to examine the differences between patients suffering from WC and a healthy control (HC) group with regard to the effective connectivity that describes causal influences one brain region exerts over another within the motor network. The effective connectivity within a network including contralateral motor cortex (M1), supplementary motor area (SMA), globus pallidus (GP), putamen (PU) and ipsilateral cerebellum (CB) was investigated using dynamic causal modeling (DCM) for fMRI. Eight connectivity models of functional motor systems were compared. Fifteen WC patients and 18 age-matched HC performed a sequential, five-element finger-tapping task with the non-dominant and non-affected left hand within a 3 T MRI-scanner as quickly and accurately as possible. The task was conducted in a fixed block design repeated 15 times and included 30 s of tapping followed by 30 s of rest. DCM identified the same model in WC and HC as superior for reflecting basal ganglia and cerebellar motor circuits of healthy subjects. The M1-PU, as well as M1-CB connectivity, was more strongly influenced by tapping in WC, but the intracortical M1-SMA connection was more facilitating in controls. Inhibiting influences originating from GP to M1 were stronger in controls compared to WC patients whereby facilitating influences the PU exerts over CB and CB exerts over M1 were not as strong. Although the same model structure explains the given data best, DCM confirms previous research demonstrating a malfunction in effective connectivity intracortically (M1-SMA) and in the cortico-basal ganglia circuitry in WC. In addition, DCM analysis demonstrates abnormal reciprocal excitatory connectivity in the cortico-cerebellar circuitry. These results highlight the dysfunctional cerebello-cortical as well as basalganglio-cortical interaction in WC., Highlights • Effective connectivity in writer`s cramp differs under sequential finger movements. • We found a deficient inhibitory pallido-cortical connectivity in writer`s cramp. • We found a diverging effective connectivity in the cortico-cerebellar loop. • We found a diverging effective connectivity in the cortico-basal ganglia pathway. • Pathophysiological interaction between the cerebellum and the basal ganglia.

Objectives: To characterize neurophysiological subcortical abnormalities in myoclonus-dystonia and their modulation by alcohol administration. Methods: Cerebellar associative learning and basal ganglia-brainstem interaction were investigated in 17 myoclonus-dystonia patients with epsilon-sarcoglycan (SGCE) gene mutation and 21 age- and sex-matched healthy controls by means of classical eyeblink conditioning and blink reflex recovery cycle before and after alcohol intake resulting in a breath alcohol concentration of 0.08% (0.8 g/l). The alcohol responsiveness of clinical symptoms was evaluated by three blinded raters with a standardized video protocol and clinical rating scales including the Unified Myoclonus Rating Scale (UMRS) and the Burke Fahn Marsden Dystonia Rating Scale (BFMDRS). Results: Patients showed a significantly reduced number of conditioned eyeblink responses before alcohol administration compared to controls. While the conditioning response rate decreased under alcohol intake in controls, it increased in patients (ANOVA: alcohol state x Group p = 0.004). Blink reflex recovery cycle before and after alcohol intake did not differ between groups. Myoclonus improved significantly after alcohol intake (p = 0.016). The severity of action myoclonus at baseline correlated negatively with the conditioning response in classical eyeblink conditioning in patients. Interpretation: The combination of findings with reduced baseline acquisition of conditioned eyeblink responses and normal blink reflex recovery cycle in patients that improved significantly by alcohol intake suggests a crucial role of cerebellar networks in the generation of symptoms in these patients. This article is protected by copyright. All rights reserved.

The proportion of patients with functional movement disorders (FMD) is particularly high in neurology clinics. Treatment options have not been consistently developed, not well evaluated and not validated. This article presents the preliminary data on the prevalence and treatment response of patients with FMD who were treated within the framework of an early rehabilitative geriatric complex treatment at a university hospital for neurology. From July 2017 to November 2018 the prevalence, demographic and clinical parameters, and response to treatment of FMD patients were documented and compared to non-FMD patients treated at the neurogeriatric ward of the University Hospital Schleswig-Holstein, in Kiel. Clinical endpoints were the Short Physical Performance Battery (SPPB) for mobility and the Barthel index for instrumented activity of daily life (iADL). The prevalence of FMD was 11% (19/175) and predominantly observed in women (74%). Of the FMD patients nine also had a diagnosis of either idiopathic Parkinson’s disease (N = 7), dementia with Lewy bodies (N = 1) or progressive supranuclear palsy (N = 1). At admission, neither the SPPB nor the iADL differed significantly between FMD and non-FMD patients. The treatment response was comparable between the groups: SPPB change was +0.3±1.8 (mean, standard deviation) in FMD and +0.4±1.9 in non-FMD patients (p = 0.83). The iADL change was +19±15 in FMD and +18±17 in non-FMD (p = 0.83). The prevalence of FMD was unexpectedly high in the neurogeriatric ward of a German university hospital. There were comparable impairments and responses to multidisciplinary treatment in mobility and iADL between FMD and non-FMD geriatric patients, suggesting that specific and informed treatment provided by a multidisciplinary geriatric team is effective in geriatric FMD patients. Further studies of this underdiagnosed disorder in older age are warranted.

Parkinson's disease still is a clinical diagnosis. Also, the MDS Clinical Diagnostic Criteria for Parkinson's disease published in 2015 are based on clinical characteristics and were designed codifying the diagnostic process of an expert. The purpose was to support less experienced neurologists to achieve the diagnostic procedure up to the level of an expert. The criteria include both negative and positive properties. However, some features exclude patients with typical Parkinson's disease mainly during their early or late stages. These includes symptoms such as the absence of the combination of typical motor symptoms, the insufficient response to dopaminergic treatment, autonomic dysfunction, dystonia, postural instability or cognitive impairment. This chapter discusses those "atypical" symptom constellations that complicate the differential diagnosis of PD versus atypical parkinsonism and illustrates additional considerations that might be helpful to achieve a correct diagnosis.

Graphical abstract, Highlights • Comparing different sensory network models in Writeŕs cramp and healthy controls. • DCM revealed abnormal insula-striatal connectivity within the somatosensory network. • Functional network connectivity of the cortex and the cerebellums remain mainly intact., Background Writer’s cramp (WC), a task specific form of dystonia, is considered to be a motor network disorder, but abnormal sensory tactile processing has also been acknowledged. The sensory spatial discrimination threshold (SDT) can be determined with a spatial acuity test (JVP domes). In addition to increased SDT, patients with WC exhibited dysfunctional sensory processing in the sensory cortex, insula, basal ganglia and cerebellum in a functional magnetic resonance imaging (fMRI) study while performing the spatial acuity test. Objectives To assess whether effective connectivity (EC) in the sensory network including cortical, basal ganglia, thalamic and cerebellar regions of interest in WC patients is abnormal. Methods We used fMRI and applied a block design, while 19 WC patients and 13 age-matched healthy controls performed a spatial discrimination task. Before we assessed EC using dynamic causal modelling, we compared three model structures based on the current literature. We enclosed regions of interest that are established for sensory processing during right hand stimulation: Left thalamus, somatosensory, parietal and insular cortex, posterior putamen, and right cerebellum. Results The EC analysis revealed task-dependent decreased unidirectional connectivity between the insula and the posterior putamen. The connectivity involving the primary sensory cortex, parietal cortex and cerebellum were not abnormal in WC. The two groups showed no differences in their behavioural data. Conclusions Perception and integration of sensory information requires the exchange of information between the insula cortex and the putamen, a sensory process that was disturbed in WC patients.

Treatment options for spasticity include intramuscular botulinum neurotoxin A (BoNT-A) injections. Both ultrasound (US) or electromyographic (EMG) guided BoNT-A injections are employed to isolate muscles. To date, most studies have included patients naïve to BoNT-A or following a prolonged wash out phase.To determine the impact of US/EMG guided BoNT-A injections on function in outpatients with spasticity receiving an established re-injection regime.Thirty patients post-stroke were investigated in a single-blinded, randomized controlled trial using a cross-over design for the EMG and US and a parallel design for the control group. The Modified Ashworth (MAS), Disability Assessment (DAS), Quality of Life (EQ-5D), self-rating scale and Barthel Index were assessed pre- and post-BoNT-A injections of upper limb muscles by a to the injection technique blinded person.MAS improved in arm, finger and upper limb 4 weeks after BoNT-A treatment. The improvement showed no significant differences between the three injection techniques. Barthel Index, DAS and EQ-5D remained unchanged in all groups.This pilot study questions the impact of the instrumental guided injection techniques on everyday functionality in a routine clinical setting with established re-injection intervals. Larger trials are warranted with patients who are under long-term treatment on a regular basis.

We conducted a genome-wide association study of essential tremor, a common movement disorder characterized mainly by a postural and kinetic tremor of the upper extremities. Twin and family history studies show a high heritability for essential tremor. The molecular genetic determinants of essential tremor are unknown. We included 2807 patients and 6441 controls of European descent in our two-stage genome-wide association study. The 59 most significantly disease-associated markers of the discovery stage were genotyped in the replication stage. After Bonferroni correction two markers, one (rs10937625) located in the serine/threonine kinase STK32B and one (rs17590046) in the transcriptional coactivator PPARGC1A were associated with essential tremor. Three markers (rs12764057, rs10822974, rs7903491) in the cell-adhesion molecule CTNNA3 were significant in the combined analysis of both stages. The expression of STK32B was increased in the cerebellar cortex of patients and expression quantitative trait loci database mining showed association between the protective minor allele of rs10937625 and reduced expression in cerebellar cortex. We found no expression differences related to disease status or marker genotype for the other two genes. Replication of two lead single nucleotide polymorphisms of previous small genome-wide association studies (rs3794087 in SLC1A2, rs9652490 in LINGO1) did not confirm the association with essential tremor.

Objective Essential tremor is a very common disease defined by sparse clinical criteria. It is unlikely that essential tremor is an etiologically homogeneous disease. Stratifying broadly defined diseases using clinical characteristics has often aided the etiopathological understanding. Most studies of essential tremor show 2 distinct age at onset peaks: early and late. This study investigates phenotypical differences between early- and late-onset essential tremor patients. Methods We studied a sample of 1137 tremor patients. Of these patients, 978 suffered from definite or probable essential tremor. All of the patients underwent the same standardized examination encompassing, among other items, drawing of the Archimedes spiral and assessment of the Fahn-Tolosa-Marin scale. Results Two subgroups of early-onset (≤ 24 years of age, n = 317) and late-onset (≥ 46 years of age, n = 356) patients were selected based on the visual and mathematical analysis of the age-at-onset distribution. Tremor severity in both groups was comparable. Tremor progression measured as Archimedes spiral score and the Fahn-Tolosa-Marin subscales divided by the disease duration in 10-year bins was significantly faster in late-onset patients when compared with early-onset patients. Early-onset patients more frequently reported a positive family history and alcohol sensitivity of the tremor. Conclusions The age-at-onset distribution suggests a distinction between early- and late-onset tremor. Early-onset and late-onset essential tremor differ in the progression rates and the frequencies of a positive family history and history of a positive effect of alcohol on tremor. © 2016 International Parkinson and Movement Disorder Society

Writers’ cramp is a movement disorder with dystonic co-contraction of fingers and hand during writing and is part of the clinical spectrum of focal dystonias. Previous studies showed reduced striatal dopamine receptor D2 (DRD2) availability in dystonia. The expression of D2 receptors is modulated by a DRD2/ANKK1-Taq1A polymorphism (rs1800497). This study addresses the question of whether the DRD2/ANKK1-Taq1A polymorphism is a risk factor for writer’s cramp. We determined the DRD2/ANKK1-Taq1A polymorphism 34 patients with writer’s cramp compared to 67 age matched controls. 35.3% of the patients and 31.3% of our controls were assigned to the A1 genotype status (p = .7). Therefore DRD2/ANKK1-Taq1A gene is not a significant risk factor in the evolution of writer’s cramp.

Post-stroke spasticity is a disabling neurological condition and may have a significant impact on quality of life. Ability to carry out activities of daily living is often compromised and painful contractures in the affected limbs may also develop. The prevalence of spasticity may be as high as 40% within the first year after the initial stroke event. Management of this condition focuses on improving muscle tone, function and pain. IncobotulinumtoxinA is effective in treating focal spasticity.This review will summarize outcomes from incobotulinumtoxin A phase III trials in upper limb spasticity. Pharmacodynamics and pharmacokinetics will also be discussed along with future studies and possible indications. Literature searches used for this review include; PubMed and www.clinicaltrials.gov searches. Congress abstracts and case reports are not included.IncobotulinumtoxinA, is a 150 kiloDalton neurotoxin without complexing proteins and is well tolerated in patients with spasticity. There is an 80% improvement reported on spasticity and disability in several phase III studies. In the future, higher doses for upper and lower limb spasticity may be considered. Antibody formation does not seem to limit the administration of higher doses. Prospective studies are evaluating the efficacy of incobotulinumtoxin in children and adolescents with cerebral palsy. Furthermore, the clinical efficacy and immunogenic status of other botulinum neurotoxin A subtypes are currently under investigation.

Previous receptor binding studies suggest dopamine function is altered in the basal ganglia circuitry in task-specific dystonia, a condition characterized by contraction of agonist and antagonist muscles while performing specific tasks. Dopamine plays a role in reward-based learning. Using fMRI, this study compared 31 right-handed writer's cramp patients to 35 controls in reward-based learning of a probabilistic reversal-learning task. All subjects chose between two stimuli and indicated their response with their left or right index finger. One stimulus response was rewarded 80%, the other 20%. After contingencies reversal, the second stimulus response was rewarded in 80%. We further linked the DRD2/ANKK1-TaqIa polymorphism, which is associated with 30% reduction of the striatal dopamine receptor density with reward-based learning and assumed impaired reversal learning in A + subjects. Feedback learning in patients was normal. Blood-oxygen level dependent (BOLD) signal in controls increased with negative feedback in the insula, rostral cingulate cortex, middle frontal gyrus and parietal cortex (pFWE, Graphical abstract, Highlights • What is the impact of abnormal dopamine signaling on decision making in task specific dystonia? • We studied the neural response in a reinforcement context using fMRI in 31 writer's cramp patients compared to 35 controls. • Patients showed specific increased response after negative feedback in middle ACC (BA 32) • This finding demonstrated disturbed integration of reinforcement history in a task specific dystonia. • The reward system might contribute to the pathogenesis in writer’s cramp

Background. Hypokinetic dysarthria is highly prevalent in idiopathic Parkinson disease (PD), and effectiveness of high-intensity voice treatment is well established. However, the neural correlates remain largely unknown. Objective. We aimed to specify cerebral pathophysiology of hypokinetic dysarthria and treatment-induced changes using functional magnetic resonance imaging (fMRI). Methods. We used fMRI to investigate healthy controls (HCs) and patients with idiopathic PD–associated dysarthria before and after treatment according to the Lee Silverman Voice Treatment LOUD (LSVT). During fMRI, participants covertly read sentences with normal (eg, conversation in a quiet room) or high (eg, shouting on a windy beach) intensity. In addition, we tested LSVT effects on intelligibility and different speech features (intensity, pitch, articulation). Results. LSVT effectively improved intelligibility, articulation, and pitch in patients. Covert high-intensity speech compared with covert normal-intensity speech led to increased activation of mainly secondary motor areas and bilateral superior and medial temporal regions. Prior to LSVT, patients showed less activity in several speech-associated areas compared with HCs. As a neural correlate of effective LSVT, increased right-sided superior temporal activity correlated with improved intelligibility. Conclusion. This is the first brain imaging study using a covert speech paradigm in PD, which revealed cortical hypoactivation as correlate of hypokinetic dysarthria. Furthermore, cortical correlates of effective LSVT treatment colocalized with the neuronal network, showing increased activation during high- versus normal-intensity speech generation.

[Background] The role of ANO3 variants as a monogenic cause of dystonia is still under debate because of its relatively high frequency also in controls., [Objective] To screen >1000 patients with movement disorders for rare ANO3 variants., [Methods] We searched for rare ANO3 variants in 729 dystonia and 294 Parkinson's disease (PD) patients using a gene panel. Variants were validated by Sanger sequencing. For one variant carrier, family members were available for segregation analysis., [Results] Nine carriers (seven with dystonia [1.0%], two with PD [0.7%]) of seven different rare, protein-changing variants were identified. None of these variants has been previously reported in dystonia patients. Two of the variants in dystonia patients were found recurrently: p.Arg328Cys was detected in two Korean and p.Arg969Gln in two German patients. The frequency of these two variants in our sample seemed to be higher as in ethnically matched samples from the Genome Aggregation Database (GnomAD). Further, we identified a patient with early-onset, generalized dystonia with a de-novo variant in ANO3 (p.Val561Glu). Of note, she benefitted from deep brain stimulation., [Conclusion] This study confirms the relatively high frequency of rare, protein-changing ANO3 variants in both dystonia and non-dystonia patients indicating that not all variants contribute to the disease. Thus, disease relevance of novel variants remains difficult to interpret and functional studies are warranted for a better understanding of the role of ANO3 variants in dystonia. In contrast, de-novo variants in childhood-onset, generalized dystonia seem to represent an as yet underestimated phenotypic expression of changes in ANO3., This work was supported by the German Ministry of Education and Research (BMBF, DYSTRACT consortium, 01GM1514B, to C.K. and K.L.).

In a movement disorder clinic, 2% to 20% of patients may present with functional movement disorders (FMDs). Tremor is the most common, accounting for 50% of patients, while functional dystonia is the second most common presentation of FMDs.1 Quality of life is considerably impaired compared to that of patients with Parkinson disease.1 The clinical diagnosis is based on an algorithm including patient history, suggestive positive phenomenologic features,2 and additional electrophysiologic findings.3 FMDs are difficult to treat, but therapy should be initiated early to improve prognosis. There are only a few studies: a couple studies on motor rehabilitation with physiotherapy in a historical cohort including mixed functional movement disorders,4,5 a pilot study exploring a retrainment/biofeedback program in 10 patients with tremor,6 and a retrospective follow-up study of patients with mixed FMD treated at a specialized multidisciplinary inpatient program.7

Background and purpose This study addresses the question of whether the neuropathological findings on the olfactory bulb (OB) in idiopathic Parkinson's disease (IPD) correspond to a detectable change in volume of the OB. Additionally, the relationship between OB volume and residual olfactory function, clinical disease characteristics and age are investigated. Methods Fifty-two IPD patients were investigated and compared to 31 healthy age-matched controls. All participants were scanned using a 3 T magnetic resonance imaging MRI scanner including a T2 DRIVE sequence in coronal slices through the OB. The OB volumes were measured via manual segmentation of the OB. Olfactory testing was carried out using the Sniffin’ Sticks test battery. Results The OB volume in the IPD group was 42.1 mm³ (SD ± 11.6) for the right and 41.5 mm³ (SD ± 11.7) for the left OB and showed no difference from the controls. Additionally, there were no significant correlations between OB volume and disease characteristics such as disease duration or Unified Parkinson's Disease Rating Scale motor score. Likewise, patients’ residual smell function did not correlate with their OB volume. In contrast, controls indicated a correlation between smell function and OB volume. Conclusion The study shows that high resolution MRI does not show a detectable volume loss of the OB in PD patients. It is concluded that OB measurement using in vivo high resolution MRI at 3 T is not helpful to identify IPD.

To characterize neurophysiological subcortical abnormalities in myoclonus-dystonia and their modulation by alcohol administration.Cerebellar associative learning and basal ganglia-brainstem interaction were investigated in 17 myoclonus-dystonia patients with epsilon-sarcoglycan (SGCE) gene mutation and 21 age- and sex-matched healthy controls by means of classical eyeblink conditioning and blink reflex recovery cycle before and after alcohol intake resulting in a breath alcohol concentration of 0.08% (0.8g/l). The alcohol responsiveness of clinical symptoms was evaluated by 3 blinded raters with a standardized video protocol and clinical rating scales including the Unified Myoclonus Rating Scale and the Burke-Fahn-Marsden Dystonia Rating Scale.Patients showed a significantly reduced number of conditioned eyeblink responses before alcohol administration compared to controls. Whereas the conditioning response rate decreased under alcohol intake in controls, it increased in patients (analysis of variance: alcohol state × group, p = 0.004). Blink reflex recovery cycle before and after alcohol intake did not differ between groups. Myoclonus improved significantly after alcohol intake (p = 0.016). The severity of action myoclonus at baseline correlated negatively with the conditioning response in classical eyeblink conditioning in patients.The combination of findings of reduced baseline acquisition of conditioned eyeblink responses and normal blink reflex recovery cycle in patients who improved significantly with alcohol intake suggests a crucial role of cerebellar networks in the generation of symptoms in these patients. Ann Neurol 2017;82:543-553.

[This corrects the article DOI: 10.1371/journal.pone.0168652.].

Mutations in RAB (member of the Ras superfamily) genes are increasingly recognized as cause of a variety of disorders including neurological conditions. While musician's dystonia (MD) and writer's dystonia (WD) are task-specific movement disorders, other dystonias persistently affect postures as in cervical dystonia. Little is known about the underlying etiology. Next-generation sequencing revealed a rare missense variant (c.586A> G; p.Ile196Val) in RAB12 in two of three MD/WD families. Next, we tested 916 additional dystonia patients; 512 Parkinson's disease patients; and 461 healthy controls for RAB12 variants and identified 10 additional carriers of rare missense changes among dystonia patients (1.1%) but only one carrier in non-dystonic individuals (0.1%; p = 0.005). The detected variants among index patients comprised p.Ile196Val (n = 6); p.Ala174Thr (n = 3); p.Gly13Asp; p.Ala148Thr; and p.Arg181Gln in patients with MD; cervical dystonia; or WD. Two relatives of MD patients with WD also carried p.Ile196Val. The two variants identified in MD patients (p.Ile196Val; p.Gly13Asp) were characterized on endogenous levels in patient-derived fibroblasts and in two RAB12-overexpressing cell models. The ability to hydrolyze guanosine triphosphate (GTP), so called GTPase activity, was increased in mutants compared to wildtype. Furthermore, subcellular distribution of RAB12 in mutants was altered in fibroblasts. Soluble Transferrin receptor 1 levels were reduced in the blood of all three tested p.Ile196Val carriers. In conclusion, we demonstrate an enrichment of missense changes among dystonia patients. Functional characterization revealed altered enzyme activity and lysosomal distribution in mutants suggesting a contribution of RAB12 variants to MD and other dystonias.

Pathologic and epidemiologic studies suggest that Parkinson disease (PD) may in some cases start in the enteric nervous system and spread via the vagal nerve to the brainstem. Mounting evidence suggests that the gut microbiome plays an important role in the communication between gut and brain and that alteration of the gut microbiome is involved in the pathogenesis of numerous diseases, including Parkinson disease. The aim of this study was to determine whether Parkinson disease is associated with qualitative or quantitative changes in the gut microbiome. We analyzed the gut microbiome in 29 PD cases and 29 age-matched controls by next-generation-sequencing of the 16S rRNA gene and compared diversity indices and bacterial abundances between cases and controls. Alpha diversity measures and the abundance of major phyla did not differ between cases and controls. Beta diversity analyses and analysis on the bacterial family level revealed significant differences between cases and controls for four bacterial families. In keeping with recently published studies, Lactobacillaceae were more abundant in cases. Barnesiellaceae and Enterococcacea were also more abundant in cases in this study but not in other studies. Larger studies, accounting for drug effects and further functional investigations of the gut microbiome are necessary to delineate the role of the gut microbiome in the pathogenesis of PD. © 2017 Elsevier B.V.

Musician's dystonia (MD) affects 1% to 2% of professional musicians and frequently terminates performance careers. It is characterized by loss of voluntary motor control when playing the instrument. Little is known about genetic risk factors, although MD or writer's dystonia (WD) occurs in relatives of 20% of MD patients. We conducted a 2-stage genome-wide association study in whites. Genotypes at 557,620 single-nucleotide polymorphisms (SNPs) passed stringent quality control for 127 patients and 984 controls. Ten SNPs revealed P < 10(-5) and entered the replication phase including 116 MD patients and 125 healthy musicians. A genome-wide significant SNP (P < 5 x 10(-8)) was also genotyped in 208 German or Dutch WD patients, 1,969 Caucasian, Spanish, and Japanese patients with other forms of focal or segmental dystonia as well as in 2,233 ethnically matched controls. Genome-wide significance with MD was observed for an intronic variant in the arylsulfatase G (ARSG) gene (rs11655081; P = 3.95 x 10(-9); odds ratio [OR], 4.33; 95% confidence interval [CI], 2.66-7.05). rs11655081 was also associated with WD (P = 2.78 x 10(-2)) but not with any other focal or segmental dystonia. The allele frequency of rs11655081 varies substantially between different populations. The population stratification in our sample was modest (lambda = 1.07), but the effect size may be overestimated. Using a small but homogenous patient sample, we provide data for a possible association of ARSG with MD. The variant may also contribute to the risk of WD, a form of dystonia that is often found in relatives of MD patients. (C) 2013 International Parkinson and Movement Disorder Society

Writer's cramp patients show poor force regulation during handwriting, but also in other experimental tasks requiring fine motor control. Botulinum neurotoxin (BoNT) treatment is clinically effective in a substantial portion of writer's cramp patients, but the full mechanism of action remains enigmatic. BoNT possibly influences α- and γ-motoneurons through chemodenervation not only of extra-, but also intrafusal muscle fibres and might thus influence muscle spindle afferents. Hence, BoNT weakens injected muscles, but may also modulate sensory aspects of force control. Ten patients and 18 controls pressed their index finger on a force sensor tracking two visual targets: The first target consisted of five plateaus with successively higher force levels and alternated with ascending ramps. In the second target condition the same successive plateaus were to be reached by abrupt jumps. The generated force displayed as a time dependant curve. Root mean square of the difference between target and produced force level was calculated for each plateau / ramp / jump. Patients were treated with BoNT at week 4 and measured at baseline, weeks 2, 4, 6 and 8. Disturbed force regulation in patients for the plateaus and the second jump at baseline resolved after BoNT treatment, and the root mean square of force deviation decreased for the ramps. Fine force control was within the 95 % confidence interval of the control group after treatment. In conclusion, force regulation was disturbed in patients and improved after BoNT treatment. This is not compatible with a simple muscle weakening and might thus reflect improved sensorimotor integration.

Facial allotransplantation has been advanced in several European countries, the United States, and China. Few full-face transplantations have been reported. The cosmetic, functional, and sensory results have been good after several months. Possible underlying mechanisms for the almost normal sensory outcome include sensory nerve repair, intact receptor density, and the interaction between facial and trigeminal nerve afferents.1

This review describes the most recent advances in epidemiology, classification, genetics, pathology and treatment of essential tremor. In addition, recent advances in more rare forms of tremor are summarized.Clinical, biochemical, pathological and imaging studies suggest an abnormal functioning of the cerebellum in essential tremor. Minor changes of cognition and personality may be due to secondary effects. Dementia and possible shortened life span seem to be limited to late-onset essential tremor. Many of these issues are not yet finally settled and need confirmation in further studies. The current essential tremor classification seems not to reflect the variety of phenotypic expressions. Regarding treatment, there is now a level B evidence for topiramate. Levetiracetam may induce a positive response in Holmes tremor, but is ineffective in orthostatic tremor.These findings have extended our knowledge about essential tremor. It appears that a new, more distinct classification system is required. Recent treatments have remained unchanged.

Classical Parkinsonian rest tremor typically fluctuates over time and can be provoked by stressful situations. We quantified and compared the influence of different provocation methods on classical rest tremor severity. The effect of counting backwards from 100, tapping of the contralateral foot and a Stroop test on the Unified Parkinson's Disease Rating Scale (UPDRS) III rest tremor scores and the accelerometrically measured tremor amplitudes (total power) were analyzed in 18 patients with Parkinson's disease and a Type I tremor. Each of the three provocation methods increased the UPDRS III rest tremor score by 1-2 and the total power by 1-2 orders of magnitude compared with baseline (P < 0.001). The maximal effect was reached on average after 2-3 minutes of provocation. The effects were not significantly different. Provocations clearly influence the result of clinical rest tremor ratings, with the kind of provocation being of minor importance. We therefore suggest that each assessment of Parkinsonian rest tremor should include a systematic provocation and this should be formally included in future versions of the UPDRS.

Lohmann, Katja et al., Specific mutations in COL6A3 have recently been reported as the cause of isolated recessive dystonia, which is a rare movement disorder. In all patients, at least one mutation was located in Exons 41 and 42. In an attempt to replicate these findings, we assessed by direct sequencing the frequency of rare variants in Exons 41 and 42 of COL6A3 in 955 patients with isolated or combined dystonia or with another movement disorder with dystonic features. We identified nine heterozygous carriers of rare variants including five different missense mutations and an extremely rare synonymous variant. In these nine patients, we sequenced the remaining 41 coding exons of COL6A3 to test for a second mutation in the compound heterozygous state. In only one of them, a second rare variant was identified (Thr732Met + Pro3082Arg). Of note, this patient had been diagnosed with Parkinson¿s disease (with dystonic posturing) due to homozygous PINK1 mutations. The COL6A3 mutations clearly did not segregate with the disease in the four affected siblings of this family. Further, there was no indication for a disease-modifying effect of the COL6A3 mutations since disease severity or age at onset did not correlate with the number of COL6A3 mutated alleles in this family. In conjunction with the relatively high frequency of homozygous carriers of reported mutations in publically available databases, our data call a causal role for variants in COL6A3 in isolated dystonia into question., This study was supported by funding from the German Research Foundation (LO1555/8-1 to K.L.). S.Z. is supported by an intramural grant of the University of Luebeck (E36-2014). She received honoraria for lectures from St. Jude Medical. A.A.K. and P.K. are supported by the German Research Foundation (KFO247). H.-C.J. has received funding from the Dystonia Coalition (NS065701; The Dystonia Coalition is part of the NIH Rare Diseases Clinical Research Network and has support from the NIH Office of Rare Diseases Research and National Institute of Neurological Disorders and Stroke). S.J.C. is supported by a grant of the Korea Healthcare Technology R & D Project, Ministry of Health & Welfare, Republic of Korea (HI14C2206). A.M. is supported by the Possehl Foundation (Lübeck, Germany) and the Dystonia Coalition (USA). C.K. is a recipient of a career development award from the Herman and Lilly Schilling Foundation.

Essential tremor is a very common disease defined by sparse clinical criteria. It is unlikely that essential tremor is an etiologically homogeneous disease. Stratifying broadly defined diseases using clinical characteristics has often aided the etiopathological understanding. Most studies of essential tremor show 2 distinct age at onset peaks: early and late. This study investigates phenotypical differences between early- and late-onset essential tremor patients.We studied a sample of 1137 tremor patients. Of these patients, 978 suffered from definite or probable essential tremor. All of the patients underwent the same standardized examination encompassing, among other items, drawing of the Archimedes spiral and assessment of the Fahn-Tolosa-Marin scale.Two subgroups of early-onset (≤ 24 years of age, n = 317) and late-onset (≥ 46 years of age, n = 356) patients were selected based on the visual and mathematical analysis of the age-at-onset distribution. Tremor severity in both groups was comparable. Tremor progression measured as Archimedes spiral score and the Fahn-Tolosa-Marin subscales divided by the disease duration in 10-year bins was significantly faster in late-onset patients when compared with early-onset patients. Early-onset patients more frequently reported a positive family history and alcohol sensitivity of the tremor.The age-at-onset distribution suggests a distinction between early- and late-onset tremor. Early-onset and late-onset essential tremor differ in the progression rates and the frequencies of a positive family history and history of a positive effect of alcohol on tremor. © 2016 International Parkinson and Movement Disorder Society.

Background Improvement of essential tremor (ET) amplitude after alcohol ingestion is usually based on patient reports but a quantitative test for large numbers of patients is lacking and the percentage of ET patients with a detectable alcohol effect is therefore unknown. Methods A validated and published alcohol home test was used in 104 ET patients. The Archimedes spiral was drawn before alcohol ingestion and at 4 time points after alcohol consumption and rated on a 10-point rating scale according to Bain and Findley. A second identical test without alcohol ingestion was performed by the same patients and evaluated by the same two raters to analyze the total variability of the spiral ratings. Results Alcohol reduces tremor in ET patients as a group and a rebound effect with an increase in tremor intensity was found the next morning. Sex, family history of ET, diagnosis (definite vs. probable) and medical history of alcohol responsiveness do not predict the alcohol response. The minimal detectable difference in the spiral score was 2 due to spontaneous tremor fluctuations and inter-rater differences. The test demonstrated alcohol sensitivity of the tremor in 46% of the patients. Responsivity to alcohol could only be seen in patients with spiral scores above 3. Conclusions Alcohol sensitivity is a feature of ET in at least 46% of the patients. We could not find predictors for alcohol sensitivity. The minimal detectable change is 2 scores and alcohol responsivity was only detected in patients with baseline Archimedes spiral rating of ≥3.