There is good evidence that synaptic plasticity in human motor cortex is involved in behavioural motor learning; in addition, it is now possible to probe mechanisms of synaptic plasticity using a variety of transcranial brain-stimulation protocols. Interactions between these protocols suggest that they both utilise common mechanisms. The aim of the present experiments was to test how well responsiveness to brain-stimulation protocols and behavioural motor learning correlate with each other in a sample of 21 healthy volunteers. We also examined whether any of these measures were influenced by the presence of a Val66Met polymorphism in the BDNF gene since this is another factor that has been suggested to be able to predict response to tests of synaptic plasticity. In 3 different experimental sessions, volunteers underwent 5-Hz rTMS, intermittent theta-burst stimulation (iTBS) and a motor learning task. Blood samples were collected from each subject for BDNF genotyping. As expected, both 5-Hz rTMS and iTBS significantly facilitated MEPs. Similarly, as expected, kinematic variables of finger movement significantly improved during the motor learning task. Although there was a significant correlation between the effect of iTBS and 5-Hz rTMS, there was no relationship in each subject between the amount of TMS-induced plasticity and the increase in kinematic variables during motor learning. Val66Val and Val66Met carriers did not differ in their response to any of the protocols. The present results emphasise that although some TMS measures of cortical plasticity may correlate with each other, they may not always relate directly to measures of behavioural learning. Similarly, presence of the Val66Met BDNF polymorphism also does not reliably predict responsiveness in small groups of individuals. Individual success in behavioural learning is unlikely to be closely related to any single measure of synaptic plasticity.

Essential tremor (ET) is one of the most common movement disorders of adults, characterized by postural and kinetic tremor. It often causes embarrassment and more rarely serious disability, requiring treatment. To assess the current state of knowledge on ET therapy and produce recommendations based on the analysis of evidence the authors reviewed the literature regarding pharmacologic and surgical therapies, providing a quality assessment of the studies and the strength of recommendations for each treatment. A committee of experts selected clinical-based questions to guide the search. A systematic literature review was performed to identify all the studies conducted on patients with ET published until September 2010. Articles were classified according to GRADE evidence profile, a system for grading the quality of evidence and the strength of recommendation based on the quality of the studies. The quality of evidence was often rated as "low" or "very low" for the studies analyzed. Propranolol, long-acting propranolol, primidone, and topiramate are recommended as first-line therapy, with restrictions for their side effects. Arotinolol, sotalol, ICI 118.551 and LI 32.468 (experimental drugs), zonisamide, gabapentin, alprazolam, clozapine, and olanzapine are recommended as a second-line treatment. Botulinum toxin type A and thalamic deep-brain stimulation are recommended for refractory ET. The results highlight the need of well-designed direct comparison trials aimed at evaluating relative effectiveness and safety of the drugs currently used in clinical practice. Furthermore, additional controlled clinical trials are required to define other possible treatment strategies for ameliorating the management of ET.

The geste antagoniste (GA), a relatively common feature of adult-onset primary dystonia, has been systematically evaluated only in cervical dystonia, but it is still unclear whether its frequency and phenomenology differ among the various forms of focal dystonia. We analysed the frequency, phenomenology, effectiveness, and relationship of the GA with demographic/clinical features of dystonia in a representative clinical series of patients with the two most common forms of adult-onset primary dystonia, blepharospasm (BSP) and cervical dystonia (CD). Clinical data were gathered using a standardized questionnaire, which showed substantial test-retest reliability (kappa = 0.79, P < 0.00001). The frequency of GA was similar among patients with BSP (42/59, 71.2%) and patients with CD (27/32, 84.4%), and in both groups GA showed similar effectiveness in reducing dystonia. The repertoire of GA was heterogenous in both BSP and CD patients, in whom seven BSP-related and five CD-related types of GA were recorded, and a "forcible" type of GA was present in 69% of BSP patients and in 48.1% of CD patients. In our whole patient population, age at dystonia onset was significantly lower among patients reporting a GA compared to those without GA (P = 0.01). GA features shared by BSP and CD predominate over differences, suggesting common mechanisms underlying this phenomenon in the two forms of primary adult-onset dystonia.

Background: Sleep disturbances are common in patients with movement disorders. Evaluating quality of sleep is of primary importance because of the effect that nocturnal and daytime sleep abnormalities exert on general health status. However, quality of sleep has never been addressed in detail in patients with dystonia. The aim of this case-control study was to analyse quality of sleep in patients with the two most common forms of primary focal dystonia, blepharospasm (BSP) and cervical dystonia (CD). Methods: We evaluated quality of sleep (Pittsburgh Sleep Quality Index, PSQI) and excessive daytime sleepiness (Epworth Sleepiness Scale, ESS) in 98 patients with focal adult-onset dystonia (52 with BSP; 46 with CD) and in a group of 56 age-and gendermatched healthy subjects. The Beck Depression Inventory (BDI) was used for the evaluation of depressive symptomatology. Results: Quality of sleep was impaired (significantly higher PSQI scores) in both groups of patients. However, differences in PSQI scores between patients with CD and control subjects were partly confounded by BDI scores, whereas differences in PSQI scores between patients with BSP and control subjects were not influenced by BDI. Excessive daytime sleepiness was not significantly more frequent than in control subjects in either patients with BSP or patients with CD. Conclusions: This study suggests that the assessment and treatment of insomniarelated complaints should be considered in global management plans of patients with focal dystonia, particularly in those affected by BSP.

SPECT imaging is widely used for the differential diagnosis of degenerative parkinsonisms by exploiting the high affinitiy of the radiotracer (123)I-FP-CIT for the dopamine transporter. Reduced levels of DAT are found in Parkinson Disease (PD), Dementia with Lewy Bodies (DLB), and Progressive Supranuclear Palsy (PSP) compared to in Essential Tremor (ET) and Healthy Controls (HC). However, the extent of the neurodegenerative process may extend beyond nigrostriatal system. We have exploited the affinity of the same radiotracer (123)I-FP-CIT for the serotonin transporter to investigate SERT levels in the midbrain of patients with PD, DLB, PSP, and ET compared to HC. Using MRI images as anatomical templates for midbrain uptake quantification, we found a mild decrease in SERT levels in PD compared to ET and HC, with marked inter-individual variability; on the other side, PSP and DLB patients displayed markedly reduced to undetectable levels of SERT, respectively. These findings show that the neurodegenerative process affects serotoninergic neurons in parkinsonisms, with much more severe involvement in DLB than in PD patients, despite the comparable loss of striatal DAT. SERT-dependent (123)I-FP-CIT uptake may allow a more comprehensive assessment of neurochemical disturbances in degenerative parkinsonisms and may have a value for differential diagnosis.