French guidelines for the diagnosis and management of Tourette syndrome.

The term "Gilles de la Tourette syndrome", or the more commonly used term "Tourette syndrome" (TS) refers to the association of motor and phonic tics which evolve in a context of variable but frequent psychiatric comorbidity. The syndrome is characterized by the association of several motor tics and at least one phonic tic that have no identifiable cause, are present for at least one year and appear before the age of 18. The presence of coprolalia is not necessary to establish or rule out the diagnosis, as it is present in only 10% of cases. The diagnosis of TS is purely clinical and is based on the symptoms defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). No additional tests are required to confirm the diagnosis of TS. However, to exclude certain differential diagnoses, further tests may be necessary. Very frequently, one or more psychiatric comorbidities are also present, including attention deficit hyperactivity disorder, obsessive-compulsive disorder, anxiety, explosive outbursts, self-injurious behaviors, learning disorders or autism spectrum disorder. The condition begins in childhood around 6 or 7 years of age and progresses gradually, with periods of relative waxing and waning of tics. The majority of patients experience improvement by the end of the second decade of life, but symptoms may persist into adulthood in around one-third of patients. The cause of TS is unknown, but genetic susceptibility and certain environmental factors appear to play a role. The treatment of TS and severe forms of tics is often challenging and requires a multidisciplinary approach (involving the general practitioner (GP), pediatrician, psychiatrist, neurologist, school or occupational physicians, psychologist and social workers). In mild forms, education (of young patients, parents and siblings) and psychological management are usually recommended. Medical treatments, including antipsychotics, are essential in the moderate to severe forms of the disease (i.e. when there is a functional and/or psychosocial discomfort linked to tics). Over the past decade, cognitive-behavioral therapies have been validated for the treatment of tics. For certain isolated tics, botulinum toxin injections may also be useful. Psychiatric comorbidities, when present, often require a specific treatment. For very severe forms of TS, treatment by deep brain stimulation offers real therapeutic hope. If tics are suspected and social or functional impairment is significant, specialist advice should be sought, in accordance with the patient's age (psychiatrist/child psychiatrist; neurologist/pediatric neurologist). They will determine tic severity and the presence or absence of comorbidities. The GP will take over the management and prescription of treatment: encouraging treatment compliance, assessing side effects, and combating stigmatization among family and friends. They will also play an important role in rehabilitation therapies, as well as in ensuring that accommodations are made in the patient's schooling or professional environment.

STW5 (Iberogast®) for constipation in Parkinson's disease.

BACKGROUND: Chronic constipation is one of the most frequent non-motor symptoms in Parkinson's disease (PD), and impairs patients' quality of life. OBJECTIVE: The aim of this pilot study was to assess the efficacy and the tolerability of STW5, a phytotherapeutic agent composed of nine plant extracts, for the treatment of constipation in patients with PD. METHODS: We carried out an open monocentric study of STW5 in the treatment of constipation in parkinsonian patients. Forty-four PD patients with a mean age of 66.4±7.3 years (range, 35-78), a mean disease duration of 12.6±5.4 years (range, 3-27) and with constipation defined by Rome III criteria for functional constipation were included. Following a two-week laxative-free baseline period, all the patients were treated with 20 drops STW5 t.i.d for 28 days, after a seven-day titration period. Treatment efficacy was defined as marked improvement of stool frequency with an increase of three exonerations during the last week of treatment when compared to the week before the initiation of treatment. Responder rate for stool frequency was estimated at 29/45 patients. RESULTS: An increase of stool frequency≥three eliminations/week was observed in only four out of 44 patients (9.0%) at the end of the study. The only significant difference observed before and after treatment was a decrease in stool consistency (P=0.0272). CONCLUSIONS: Our results suggest that STW5 has a safety profile but is not effective as a phytotherapeutic agent in constipation related to Parkinson's disease.

Pathophysiology of Parkinson's disease: Mitochondria, alpha-synuclein and much more .

Parkinson's disease (PD) is a complex, age-related, neurodegenerative disease whose pathogenesis remains incompletely understood. Here, we give an overview of the progress that has been made over the past four decades in our understanding of this disorder. We review the role of mitochondria, environmental toxicants, alpha-synuclein and neuroinflammation in the development of PD. We also discuss more recent data from genetics, which strongly support the endosomal-lysosomal pathways and mitophagy as being central to PD. Finally, we discuss the emerging role of the gut-brain axis as a modulator of PD progression. This article is intended to provide a comprehensive, general and practical review of PD pathogenesis for the general neurologist.

Autosomal dominant SPG9: intrafamilial variability and onset during pregnancy.

INTRODUCTION: The ALDH18A1 gene, encoding delta-1-pyrroline-5-carboxylate synthase (P5CS), is responsible for an autosomal recessive disease with severe developmental delay; more recently, ALDH18A1 was found to be responsible for SPG9, an autosomal dominant (AD) spastic paraplegia. CASE REPORT: We report a three-generation family with AD SPG9, initially suspected because of low citrulline on fasting plasma amino acid chromatography (AAC). Interestingly, in two patients, the spastic paraplegia appeared during pregnancy. One subject presented a severe childhood-onset form while another subject had a mild late-onset disease. CONCLUSION: The description of this family is of particular interest: it highlights the possibility of transient or permanent aggravation of spastic paraplegia due to SPG9 during pregnancy, suggesting a direct link between neurological symptoms and amino acid defect in a period of higher requirements and the potential benefit of amino acid supplementation; it underscores the value of plasma citrulline on fasting plasma AAC as a biomarker for this disease; it shows the variable expression of the disease.

How do Parkinson's disease patients manage Ramadan fasting? An observational study.

Twenty-four Parkinson's disease (PD) patients who had planned to fast during the 2016 Ramadan were included in this observational study. Twenty patients fasted during the whole Ramadan. Six were able to abstain from drug intakes from dawn to dusk; the others needed 1 or 2 intakes of L-DOPA during the day. There were no serious side effects reported during the Ramadan period. Compared to before Ramadan, there were no significant changes after the fasting period in quality of life (PDQ 39), non-motor symptom scale or clinical impression of severity index scores.

High-dose transdermal nicotine in Parkinson's disease patients: a randomized, open-label, blinded-endpoint evaluation phase 2 study.

BACKGROUND AND PURPOSE: Studies of the effects of nicotine on motor symptoms in Parkinson's disease (PD) brought out discordant results. The aim of the present study was to evaluate the efficacy and safety of high doses of transdermal nicotine on motor symptoms in PD. METHODS: Forty PD patients were randomly assigned to a treated and untreated arm in an open-label study. Treated patients received increasing doses of nicotine to reach 90 mg/day by 11 weeks. This dosage was maintained for 28 weeks (W39) and then reduced over 6 weeks. Final evaluation was performed 6 weeks after washout. The main outcome measure was the OFF-DOPA Unified Parkinson's Disease Rating Scale (UPDRS) motor score measured on video recordings by raters blinded to the medication status of the patients. RESULTS: There was no significant difference in OFF-DOPA UPDRS motor scores between the nicotine-treated and non-treated groups, neither at W39 (19.4 ± 9.3 vs. 21.5 ± 14.2) nor considering W39 differences from baseline (-1.5 ± 12.1 vs. +0.9 ± 12.1). The 39-item Parkinson's disease questionnaire scores decreased in nicotine-treated patients and increased in non-treated patients, but the difference was not significant. Overall tolerability was acceptable, and 12/20 treated patients reached the maximal dosage. CONCLUSIONS: High doses of transdermal nicotine were tolerated, but our study failed to demonstrate significant improvement in UPDRS motor scores. Improvement in unblinded secondary outcomes (UPDRS-II, UPDRS-IV, doses of l-DOPA equivalents) suggest a possible benefit for patients treated with nicotine, which should be confirmed in larger double blind, placebo-controlled studies.

L-DOPA-induced dyskinesias, motor fluctuations and health-related quality of life: the COPARK survey.

BACKGROUND AND PURPOSE: Studies assessing the correlations between L-DOPA-induced dyskinesias (LIDs) and motor fluctuations with health-related quality of life (HRQoL) in Parkinson's disease (PD) have yielded conflicting results. This study aimed to assess the relationship between LIDs and motor fluctuations with HRQoL in patients with PD, and to assess the relative contribution of their severity and duration in a large sample of patients with PD. METHODS: A total of 683 patients with PD from the COPARK survey were evaluated. HRQoL was assessed using the 39-Item Parkinson's Disease Questionnaire (PDQ-39) (primary outcome) and 36-Item Short Form Survey (SF-36). The daily duration and severity of LIDs were obtained from Unified Parkinson's Disease Rating Scale (UPDRS) IV items 32 and 33, respectively. The daily duration of motor fluctuations was obtained from UPDRS IV item 36 and severity was estimated as the difference between the UPDRS 2 (Activities of Daily Living) score in 'OFF' versus 'ON' condition. RESULTS: A total of 235 patients with PD (35%) experienced motor fluctuations and 182 (27%) experienced LIDs. The PDQ-39 total and SF-36 physical scores were significantly worse in patients with LIDs, after adjusting for the presence of motor fluctuations. The PDQ-39 total score and SF-36 physical and mental score were significantly worse in patients with motor fluctuations, after adjusting for the presence of LIDs. The severity of LIDs and the duration of motor fluctuations significantly and independently affected PDQ-39 scores. The SF-36 physical score was affected only by the severity of motor fluctuations, whereas the mental score was not affected by any of the aforementioned variables. CONCLUSION: Our findings suggest that LIDs (mainly their severity) and motor fluctuations (mainly their duration) correlate independently with HRQoL in patients with PD.

Neurostimulation for Parkinson's disease with early motor complications.

BACKGROUND: Subthalamic stimulation reduces motor disability and improves quality of life in patients with advanced Parkinson's disease who have severe levodopa-induced motor complications. We hypothesized that neurostimulation would be beneficial at an earlier stage of Parkinson's disease. METHODS: In this 2-year trial, we randomly assigned 251 patients with Parkinson's disease and early motor complications (mean age, 52 years; mean duration of disease, 7.5 years) to undergo neurostimulation plus medical therapy or medical therapy alone. The primary end point was quality of life, as assessed with the use of the Parkinson's Disease Questionnaire (PDQ-39) summary index (with scores ranging from 0 to 100 and higher scores indicating worse function). Major secondary outcomes included parkinsonian motor disability, activities of daily living, levodopa-induced motor complications (as assessed with the use of the Unified Parkinson's Disease Rating Scale, parts III, II, and IV, respectively), and time with good mobility and no dyskinesia. RESULTS: For the primary outcome of quality of life, the mean score for the neurostimulation group improved by 7.8 points, and that for the medical-therapy group worsened by 0.2 points (between-group difference in mean change from baseline to 2 years, 8.0 points; P=0.002). Neurostimulation was superior to medical therapy with respect to motor disability (P<0.001), activities of daily living (P<0.001), levodopa-induced motor complications (P<0.001), and time with good mobility and no dyskinesia (P=0.01). Serious adverse events occurred in 54.8% of the patients in the neurostimulation group and in 44.1% of those in the medical-therapy group. Serious adverse events related to surgical implantation or the neurostimulation device occurred in 17.7% of patients. An expert panel confirmed that medical therapy was consistent with practice guidelines for 96.8% of the patients in the neurostimulation group and for 94.5% of those in the medical-therapy group. CONCLUSIONS: Subthalamic stimulation was superior to medical therapy in patients with Parkinson's disease and early motor complications. (Funded by the German Ministry of Research and others; EARLYSTIM ClinicalTrials.gov number, NCT00354133.).

Oro-buccal symptoms (dysphagia, dysarthria, and sialorrhea) in patients with Parkinson's disease: preliminary analysis from the French COPARK cohort.

INTRODUCTION: Abnormal oro-buccal functions including dysarthria, sialorrhea and dysphagia commonly affect patients with Parkinson's disease (PD). OBJECTIVES: To estimate the prevalence of such oro-buccal symptoms at baseline in the first 419 patients with PD included in the COPARK cohort and to analyze their correlations with patients' demographics, clinical characteristics, and drugs consumption. METHODS: Patients were assessed using the Unified PD Rating Scale, the Hospital Anxiety and Depression Scale, and the PDQ-39. Dysarthria, sialorrhea, and dysphagia were defined as UPDRS items 5, 6, or 7 ≥ 1. RESULTS: Dysarthria, sialorrhea, or dysphagia were present in 51%, 37%, or 18% out of the 419 patients, respectively. At least one of these symptom was present in 267/419 patients (65%), whilst a combination of symptoms was present in 136/419 (33%). Logistic regression showed that the presence of each of the three oro-buccal symptoms was significantly correlated with that of the two others. Other correlations included male gender, hallucinations, disease severity, levodopa use and lack of opiates consumption for dysarthria; disease severity, orthostatic hypotension and absence of antidepressants consumption for sialorrhea; female gender, motor fluctuations, and depressive symptoms for dysphagia. None of the three oro-buccal symptoms were associated with a reduced PDQ-39 score. CONCLUSION: Oro-buccal symptoms were present in two of three patients with moderate PD, the presence of each symptoms being significantly correlated with that of the two others.

Molecular analyses of the LRRK2 gene in European and North African autosomal dominant Parkinson's disease.

BACKGROUND: Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene have been identified in families with autosomal dominant Parkinson's disease (ADPD), the most common of which is the p.G2019S substitution that has been found at varying frequencies worldwide. Because of the size of the LRRK2 gene, few studies have analysed the entire gene in large series of ADPD families. METHODS: We performed extensive mutation analyses of all 51 coding exons of the LRRK2 gene in index cases from 226 Parkinson's disease families compatible with autosomal dominant inheritance, mostly from France (n = 182) and North Africa (n = 14). RESULTS: We found 79 sequence variants, 29 of which were novel. Eight potentially or proven pathogenic mutations were found in 22 probands (9.7%). There were four novel amino acid substitutions that are potentially pathogenic (p.S52F, p.N363S, p.I810V, p.R1325Q) and two novel variants, p.H1216R and p.T1410M, that are probably not causative. The common p.G2019S mutation was identified in 13 probands (5.8%) including six from North Africa (43%). The known heterozygous p.R1441H and p.I1371V mutations were found in two probands each, and the p.E334K variant was identified in one single patient. Most potentially or proven pathogenic mutations were located in the functional domains of the Lrrk2 protein. CONCLUSION: This study leads us to conclude that LRRK2 mutations are a common cause of autosomal dominant Parkinson's disease in Europe and North Africa.

Penetrance of marked cognitive impairment in older male carriers of the FMR1 gene premutation.

BACKGROUND: Male carriers of the FMR1 premutation are at risk of developing the fragile X-associated tremor/ataxia syndrome (FXTAS), a newly recognised and largely under-diagnosed late onset neurodegenerative disorder. Patients affected with FXTAS primarily present with cerebellar ataxia and intention tremor. Cognitive decline has also been associated with the premutation, but the lack of data on its penetrance is a growing concern for clinicians who provide genetic counselling. METHODS: The Mattis Dementia Rating Scale (MDRS) was administered in a double blind fashion to 74 men aged 50 years or more recruited from fragile X families (35 premutation carriers and 39 intrafamilial controls) regardless of their clinical manifestation. Based on previous publications, marked cognitive impairment was defined by a score

Levodopa/DDCI and entacapone is the preferred treatment for Parkinson's disease patients with motor fluctuations in routine practice: a retrospective, observational analysis of a large French cohort.

Levodopa is the gold standard drug for the symptomatic control of Parkinson's disease (PD). However, long-term treatment with conventional formulations [levodopa and a dopa decarboxylase inhibitor (DDCI)], is associated with re-emergence of symptoms because of wearing-off and dyskinesia. Treatment with levodopa/DDCI and entacapone extends the half-life of levodopa, avoiding deep troughs in levodopa plasma levels and providing more continuous delivery of levodopa to the brain. In this open-label, retrospective, observational study we investigated the effects of levodopa/DDCI and entacapone therapy in 800 PD patients with motor fluctuations. Levodopa/DDCI and entacapone treatment was assessed as good/very good in improving motor fluctuations (64%) and activities of daily living (ADL; 62%). The therapeutic utility was considered to be good/very good in 70% of cases. Moreover, there was a reduction in levodopa dose in 20% of patients. Neurologists preferred levodopa/DDCI and entacapone compared with increasing levodopa dosage, dose-fractionation or addition of a dopamine agonist (63%, 29% and 23% of patients respectively). Reasons included achieving more continuous dopaminergic stimulation (40%), reducing motor fluctuations (54%) and improving ADL (41%). This analysis reveals the preference of neurologists for levodopa/DDCI and entacapone over conventional levodopa-modification strategies for the effective treatment of PD motor fluctuations in clinical practice.

Epsilon sarcoglycan mutations and phenotype in French patients with myoclonic syndromes.

BACKGROUND: Myoclonus dystonia syndrome (MDS) is an autosomal dominant movement disorder caused by mutations in the epsilon-sarcoglycan gene (SGCE) on chromosome 7q21. METHODS: We have screened for SGCE mutations in index cases from 76 French patients with myoclonic syndromes, including myoclonus dystonia (M-D), essential myoclonus (E-M), primary myoclonic dystonia, generalised dystonia, dystonia with tremor, and benign hereditary chorea. All coding exons of the SGCE gene were analysed. The DYT1 mutation was also tested. RESULTS: Sixteen index cases had SGCE mutations while one case with primary myoclonic dystonia carried the DYT1 mutation. Thirteen different mutations were found: three nonsense mutations, three missense mutations, three splice site mutations, three deletions, and one insertion. Eleven of the SGCE index cases had M-D and five E-M. No SGCE mutations were detected in patients with other phenotypes. The total number of mutation carriers in the families was 38, six of whom were asymptomatic. Penetrance was complete in paternal transmissions and null in maternal transmissions. MDS patients with SGCE mutation had a significantly earlier onset than the non-carriers. None of the patients had severe psychiatric disorders. CONCLUSION: This large cohort of index patients shows that SGCE mutations are primarily found in patients with M-D and to a lesser extent E-M, but are present in only 30% of these patients combined (M-D and E-M).

[Presentation of cerebral toxocariasis with mental confusion in an adult: case report and review of the literature]. / Toxocarose cérébrale révélée par une confusion mentale chez un adulte à Nantes: cas clinique et revue de la littérature.

Toxocariasis is usually responsible for visceral larva migrans syndroms. Nervous system involvement is a rare complication. In this report, we describe one case of meningoencephalitis due to Toxocara canis in a 73-year-old man presenting with mental confusion. The diagnosis of cerebral toxocariasis was confirmed by immunodiagnosis in both serum and cerebro-spinal fluid. Cerebral toxocariasis may be suspected in patients presenting with some neurological patterns including: confusion, meningitis, meningo-encephalitis, meningo-myelitis, when the etiological assessment remains negative and the environmental context is favourable. Finding evidence of specific antibodies in both cerebro spinal fluid and serum is mandatory for the diagnosis. The main clinical features concerning cerebral toxocariasis, diagnostic tools, and therapeutic measures are discussed.

[Idiopathic acute transverse myelitis: application of new diagnosis criteria to 17 patients]. / Myélite aiguë transverse idiopathique: application des nouveaux critères diagnostiques à une cohorte de 17 patients.

INTRODUCTION: Idiopathic Acute Transverse Myelitis (ATM) is an inflammatory and immune-mediated disorder, distinct from infectious ATM, ATM of systemic lupus erythematosus or Sjögren's syndrome, and medullary manifestation of multiple sclerosis. Prognosis is not well-known. OBJECTIVE: To evaluate clinical, paraclinical and pronognosis data in patients selected with new diagnosis criteria, classically described in idiopathic ATM. METHODS: Seventeen patients with diagnosis criteria were retrospectively (1996-2005) studied. A telephone investigation was conducted in 2005 to obtained data on the clinical course. RESULTS: Seven men and 10 women, ranging in age from 15 to 75 years (mean: 39.8 years) met these new criteria. Our study showed that epidemiological and clinical findings as well as laboratory results were in agreement with those presented in the literature. Conversely, prognosis was better since 76p.cent of the patients could walk without assistance. The clinical presentation of some of our patients and/or their progression towards other multifocal inflammatory disorders, suggests there might be links between ATM, neuromyelitis optica (NMO) and Acute Dissemined Encephalomyelitis (ADEM). CONCLUSION: Patients with idiopathic ATM, selected with new criteria, have a rather good prognosis. ATM seems to be part of a continuum of neuroimmunologic disorders including NMO or ADEM although reasons explaining distinct focal disorders remain unclear.

Subthalamic stimulation in Parkinson disease: a multidisciplinary approach.

BACKGROUND: High-frequency stimulation of the subthalamic nucleus constitutes a therapeutic advance for severely disabled patients with Parkinson disease. OBJECTIVE: To evaluate the efficacy and safety of continuous bilateral high-frequency stimulation of the subthalamic nucleus in patients with Parkinson disease. DESIGN: A prospective study of patients with Parkinson disease treated at a university hospital. PATIENTS AND METHODS: Electrodes were implanted bilaterally in the subthalamic nucleus of 23 consecutive patients with Parkinson disease who responded well to levodopa but had severe motor complications. There were 16 men and 7 women (mean +/- SEM age, 53 +/- 2 years) who had a mean +/- SEM disease duration of 14.7 +/- 1.0 years. Targets were determined by 3-dimensional magnetic resonance imaging, combined with intraoperative electrophysiologic recordings and stimulation. RESULTS: Six months after surgery, motor disability, levodopa-induced motor fluctuations, dyskinesias, and the daily dose of levodopa equivalent decreased significantly by 67%, 78%, 77%, and 61%, respectively, compared with the preoperative state. No significant morbidity was observed, except transient depression in 4 patients. CONCLUSIONS: The beneficial effects of subthalamic stimulation depend on (1) the criteria used for patient selection, (2) the precision with which the subthalamic nucleus is targeted (dependent on the 3-dimensional magnetic resonance imaging and the intraoperative electrophysiologic and clinical assessments), and (3) the long-term postoperative adjustment of stimulation variables.

Does monoamine oxidase type B play a role in dopaminergic nerve cell death in Parkinson's disease?

Evidence supports the role of hyperoxidation phenomena in the mechanism of nerve cell death in Parkinson's disease (PD). The oxidative degradation of dopamine, catalyzed by monoamine oxidase type B (MAO-B), produces free radicals and thus could be implicated in the degenerative process. For this reason, we investigated by immunohistochemistry the distribution of MAO-B-containing cells in the midbrain of five patients with PD and five matched control subjects. MAO-B-like immunoreactivity was detected in glial cells, fibers, and neurons. Although most of the MAO-B-positive neurons probably belonged to the raphe dorsalis, we demonstrated by double-labeling immunohistochemistry that some of them were also dopaminergic. MAO-B-positive dopaminergic neurons were present in all dopaminergic groups of the control midbrain. Within the substantia nigra pars compacta, most dopaminergic neurons were located in the dorsal part of the structure. MAO-B-positive dopaminergic neurons were still detected in PD midbrains. Compared with control subjects, the loss of dopaminergic neurons containing MAO-B (-45%) was no higher than that of MAO-B-negative dopaminergic neurons (-59%). The density of MAO-B-positive glial cells varied in the control midbrains: high in the least affected dopaminergic group (the central gray substance) and low in the most affected region (the substantia nigra pars compacta). The density of MAO-B-positive glial cells within dopaminergic cell subgroups in control midbrains were negatively correlated (r = -0.94; p < 0.02) to the estimated neuronal loss in PD. We conclude that the presence of MAO-B in dopamine-containing neurons does not contribute to vulnerability in PD. Moreover, its presence in some glial cells might have a protective effect against oxidative stress induced by dopamine metabolism.

Neuropsychological changes between "off" and "on" STN or GPi stimulation in Parkinson's disease.

BACKGROUND: In a previous study on a consecutive series of 62 patients with PD, the authors showed that bilateral subthalamic or pallidal continuous high-frequency deep brain stimulation (DBS) affects neither memory nor executive functions 3 to 6 months after surgery. OBJECTIVE: To investigate the specific effects of DBS by comparing the performance of patients with the stimulator turned "on" and "off." METHODS: The performance of 56 patients on clinical tests of executive function was compared after 3 and 12 months of DBS of the subthalamic nucleus (STN; n = 48) or the internal globus pallidus (GPi; n = 8) with the stimulator "on" or "off." Global intellectual efficiency, verbal learning, and mood were also evaluated with the stimulator "on." The performance of another group of 20 patients was compared after 6 months of DBS of the STN (n = 15) or the GPi (n = 5) with the stimulator "on" or "off" on more experimental tests recently shown to be more sensitive to l-dopa therapy. RESULTS: When the stimulator was "on," STN patients showed a mild but significant improvement in psychomotor speed and working memory. In comparison with the presurgical state, STN patients had no cognitive deficit at 12 months, except for lexical fluency. There was no differential effect of STN or GPi stimulation. CONCLUSIONS: 1) The specific effect of DBS seems to mimic the action of l-dopa treatment in the cognitive as in the motor domain; 2) the surgery associated with DBS does not appear to affect the cognitive performance of patients with PD 12 months later, except for a mild deficit in lexical fluency.

Improvement of sleep architecture in PD with subthalamic nucleus stimulation.

High-frequency stimulation of the subthalamic nucleus (STN) was used to investigate the relationship of sleep disorders with motor handicap in PD. In 10 insomniac patients with PD, stimulation reduced nighttime akinesia by 60% and completely suppressed axial and early morning dystonia, but did not alleviate periodic leg movements (n = 3) or REM sleep behavior disorders (n = 5). Total sleep time increased by 47%; wakefulness after sleep onset decreased by 51 minutes. Insomnia in patients with PD may predominantly result from nighttime motor disability.