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1.
Front Psychiatry ; 14: 1146492, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37304434

RESUMO

Crack-cocaine dependence is a severe condition with a high mortality rate. This single case study report details the first deep brain stimulation (DBS) trial targeting the sub-thalamic nucleus (STN) for crack-cocaine dependence. The investigation aimed to assess the effects of STN-DBS on cocaine craving and cocaine use, as well as STN-DBS safety and tolerance in this indication. In this pilot study, we performed double blind cross-over trials, with "ON-DBS" vs. "SHAM-DBS" for 1-month periods. STN-DBS failed to reduce cocaine craving and use. An episode of DBS-induced hypomania occurred after several weeks of cocaine intake at stimulation parameters previously well tolerated. Future research on cocaine dependence should be conducted after a prolonged abstinence period and/or explore novel types of stimulation patterns.

2.
Front Neurol ; 13: 791092, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547388

RESUMO

Background: The subthalamic nucleus (STN) is an effective neurosurgical target to improve motor symptoms in Parkinson's Disease (PD) patients. MR-guided Focused Ultrasound (MRgFUS) subthalamotomy is being explored as a therapeutic alternative to Deep Brain Stimulation (DBS) of the STN. The hyperdirect pathway provides a direct connection between the cortex and the STN and is likely to play a key role in the therapeutic effects of MRgFUS intervention in PD patients. Objective: This study aims to investigate the topography and somatotopy of hyperdirect pathway projections from the primary motor cortex (M1). Methods: We used advanced multi-fiber tractography and high-resolution diffusion MRI data acquired on five subjects of the Human Connectome Project (HCP) to reconstruct hyperdirect pathway projections from M1. Two neuroanatomy experts reviewed the anatomical accuracy of the tracts. We extracted the fascicles arising from the trunk, arm, hand, face and tongue area from the reconstructed pathways. We assessed the variability among subjects based on the fractional anisotropy (FA) and mean diffusivity (MD) of the fibers. We evaluated the spatial arrangement of the different fascicles using the Dice Similarity Coefficient (DSC) of spatial overlap and the centroids of the bundles. Results: We successfully reconstructed hyperdirect pathway projections from M1 in all five subjects. The tracts were in agreement with the expected anatomy. We identified hyperdirect pathway fascicles projecting from the trunk, arm, hand, face and tongue area in all subjects. Tract-derived measurements showed low variability among subjects, and similar distributions of FA and MD values among the fascicles projecting from different M1 areas. We found an anterolateral somatotopic arrangement of the fascicles in the corona radiata, and an average overlap of 0.63 in the internal capsule and 0.65 in the zona incerta. Conclusion: Multi-fiber tractography combined with high-resolution diffusion MRI data enables the identification of the somatotopic organization of the hyperdirect pathway. Our preliminary results suggest that the subdivisions of the hyperdirect pathway projecting from the trunk, arm, hand, face, and tongue motor area are intermixed at the level of the zona incerta and posterior limb of the internal capsule, with a predominantly overlapping topographical organization in both regions. Subject-specific knowledge of the hyperdirect pathway somatotopy could help optimize target definition in MRgFUS intervention.

3.
J Neurol Neurosurg Psychiatry ; 91(12): 1349-1356, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33033168

RESUMO

BACKGROUND: Obsessive-compulsive disorder (OCD) is a major cause of disability in western country and responsible for severe impairment of quality of life. About 10% of patients present with severe OCD symptoms and require innovative treatment such as deep brain stimulation (DBS). Among possible targets, the non-motor subthalamic nucleus (STN) is a key node of the basal ganglia circuitry, strongly connected to limbic cortical areas known to be involved in OCD. METHOD: We analysed, in a prospective, observational, monocentric, open label cohort, the effect of chronic non-motor STN-DBS in 19 patients with treatment-resistant OCD consecutively operated in a single centre. Severity of OCD was evaluated using the Yale and Brown Obsessive-Compulsive Scale (YBOCS). YBOCS scores at 6, 12 and 24 months postoperatively were compared with baseline. Responders were defined by >35% improvement of YBOCS scores. Global Assessment Functioning (GAF) scale was used to evaluate the impact of improvement. RESULTS: At a 24-month follow-up, the mean YBOCS score improved by 53.4% from 33.3±3.5 to 15.8±9.1 (95% CI 11.2-20.4; p<0.0001). Fourteen out of 19 patients were considered as responders, 5 out of 19 being improved over 75% and 10 out of 19 over 50%. GAF scale improved by 92% from 34.1±3.9 to 66.4±18.8 (95% CI 56.7-76.1; p=0.0003). The most frequent adverse events consisted of transient DBS-induced hypomania and anxiety. CONCLUSION: Chronic DBS of the non-motor STN is an effective and relatively safe procedure to treat severe OCD resistant to conventional management.


Assuntos
Estimulação Encefálica Profunda/métodos , Transtorno Obsessivo-Compulsivo/terapia , Núcleo Subtalâmico , Adulto , Ansiedade/etiologia , Estudos de Coortes , Estimulação Encefálica Profunda/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Mania/etiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
6.
Front Psychiatry ; 10: 905, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920754

RESUMO

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder featuring repetitive intrusive thoughts and behaviors associated with a significant handicap. Of patients, 20% are refractory to medication and cognitive behavioral therapy. Refractory OCD is associated with suicidal behavior and significant degradation of social and professional functioning, with high health costs. Deep brain stimulation (DBS) has been proposed as a reversible and controllable method to treat refractory patients, with meta-analyses showing 60% response rate following DBS, whatever the target: anterior limb of the internal capsule (ALIC), ventral capsule/ventral striatum (VC/VS), nucleus accumbens (NAcc), anteromedial subthalamic nucleus (amSTN), or inferior thalamic peduncle (ITP). But how do we choose the "best" target? Functional neuroimaging studies have shown that ALIC-DBS requires the modulation of the fiber tract within the ventral ALIC via the ventral striatum, bordering the bed nucleus of the stria terminalis and connecting the medial prefrontal cortex with the thalamus to be successful. VC/VS effective sites of stimulation were found within the VC and primarily connected to the medial orbitofrontal cortex (OFC) dorsomedial thalamus, amygdala, and the habenula. NAcc-DBS has been found to reduce OCD symptoms by decreasing excessive fronto-striatal connectivity between NAcc and the lateral and medial prefrontal cortex. The amSTN effective stimulation sites are located at the inferior medial border of the STN, primarily connected to lateral OFC, dorsal anterior cingulate, and dorsolateral prefrontal cortex. Finally, ITP-DBS recruits a bidirectional fiber pathway between the OFC and the thalamus. Thus, these functional connectivity studies show that the various DBS targets lie within the same diseased neural network. They share similar efficacy profiles on OCD symptoms as estimated on the Y-BOCS, the amSTN being the target supported by the strongest evidence in the literature. VC/VS-DBS, amSTN-DBS, and ALIC-DBS were also found to improve mood, behavioral adaptability and potentially both, respectively. Because OCD is such a heterogeneous disease with many different symptom dimensions, the ultimate aim should be to find the most appropriate DBS target for a given refractory patient. This quest will benefit from further investigation and understanding of the individual functional connectivity of OCD patients.

7.
PLoS One ; 12(11): e0186641, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29095850

RESUMO

PURPOSE: This study evaluates the correlation between injuries to deep gray matter nuclei, as quantitated by lesions in these nuclei on MR T2 Fast Spin Echo (T2 FSE) images, with 6-month neurological outcome after severe traumatic brain injury (TBI). MATERIALS AND METHODS: Ninety-five patients (80 males, mean age = 36.7y) with severe TBI were prospectively enrolled. All patients underwent a MR scan within the 45 days after the trauma that included a T2 FSE acquisition. A 3D deformable atlas of the deep gray matter was registered to this sequence; deep gray matter lesions (DGML) were evaluated using a semi-quantitative classification scheme. The 6-month outcome was dichotomized into unfavorable (death, vegetative or minimally conscious state) or favorable (minimal or no neurologic deficit) outcome. RESULTS: Sixty-six percent of the patients (63/95) had both satisfactory registration of the 3D atlas on T2 FSE and available clinical follow-up. Patients without DGML had an 89% chance (P = 0.0016) of favorable outcome while those with bilateral DGML had an 80% risk of unfavorable outcome (P = 0.00008). Multivariate analysis based on DGML accurately classified patients with unfavorable neurological outcome in 90.5% of the cases. CONCLUSION: Lesions in deep gray matter nuclei may predict long-term outcome after severe TBI with high sensitivity and specificity.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Substância Cinzenta/patologia , Avaliação de Resultados em Cuidados de Saúde , Adulto , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/fisiopatologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino
8.
Lancet Neurol ; 16(8): 610-619, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28645853

RESUMO

BACKGROUND: Deep brain stimulation (DBS) has been proposed to treat patients with severe Tourette's syndrome, and open-label trials and two small double-blind trials have tested DBS of the posterior and the anterior internal globus pallidus (aGPi). We aimed to specifically assess the efficacy of aGPi DBS for severe Tourette's syndrome. METHODS: In this randomised, double-blind, controlled trial, we recruited patients aged 18-60 years with severe and medically refractory Tourette's syndrome from eight hospitals specialised in movement disorders in France. Enrolled patients received surgery to implant bilateral electrodes for aGPi DBS; 3 months later they were randomly assigned (1:1 ratio with a block size of eight; computer-generated pairwise randomisation according to order of enrolment) to receive either active or sham stimulation for the subsequent 3 months in a double-blind fashion. All patients then received open-label active stimulation for the subsequent 6 months. Patients and clinicians assessing outcomes were masked to treatment allocation; an unmasked clinician was responsible for stimulation parameter programming, with intensity set below the side-effect threshold. The primary endpoint was difference in Yale Global Tic Severity Scale (YGTSS) score between the beginning and end of the 3 month double-blind period, as assessed with a Mann-Whitney-Wilcoxon test in all randomly allocated patients who received active or sham stimulation during the double-blind period. We assessed safety in all patients who were enrolled and received surgery for aGPi DBS. This trial is registered with ClinicalTrials.gov, number NCT00478842. FINDINGS: Between Dec 6, 2007, and Dec 13, 2012, we enrolled 19 patients. We randomly assigned 17 (89%) patients, with 16 completing blinded assessments (seven [44%] in the active stimulation group and nine [56%] in the sham stimulation group). We noted no significant difference in YGTSS score change between the beginning and the end of the 3 month double-blind period between groups (active group median YGTSS score 68·5 [IQR 34·0 to 83·5] at the beginning and 62·5 [51·5 to 72·0] at the end, median change 1·1% [IQR -23·9 to 38·1]; sham group 73·0 [69·0 to 79·0] and 79·0 [59·0 to 81·5], median change 0·0% [-10·6 to 4·8]; p=0·39). 15 serious adverse events (three in patients who withdrew before stimulation and six each in the active and sham stimulation groups) occurred in 13 patients (three who withdrew before randomisation, four in the active group, and six in the sham group), with infections in DBS hardware in four patients (two who withdrew before randomisation, one in the sham stimulation group, and one in the active stimulation group). Other serious adverse events included one electrode misplacement (active stimulation group), one episode of depressive signs (active stimulation group), and three episodes of increased tic severity and anxiety (two in the sham stimulation group and one in the active stimulation group). INTERPRETATION: 3 months of aGPi DBS is insufficient to decrease tic severity for patients with Tourette's syndrome. Future research is needed to investigate the efficacy of aGPi DBS for patients over longer periods with optimal stimulation parameters and to identify potential predictors of the therapeutic response. FUNDING: French Ministry of Health.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Globo Pálido , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença , Síndrome de Tourette/terapia , Adulto , Estimulação Encefálica Profunda/métodos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Tratamento , Adulto Jovem
9.
Neurocase ; 23(1): 84-87, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28165911

RESUMO

Depressive symptoms may occur after Deep Brain Stimulation (DBS) in the subthalamic nucleus. This is often explained by reduced pharmacological treatment after surgery, and not as a direct effect of DBS. Pallidal DBS seems not to be associated with such side effects and have not, to our knowledge, previously been reported. We present a patient with acute depressive symptoms induced by pallidal DBS. We believe this case strengthen the hypothesis that the basal ganglia and structures involved in the functional connectome of these nucleuses play a role not only in regulation of movement but also in regulation of mood.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Depressão/etiologia , Globo Pálido/fisiologia , Depressão/diagnóstico por imagem , Globo Pálido/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/terapia , Escalas de Graduação Psiquiátrica , Tomografia Computadorizada por Raios X
10.
Mov Disord ; 31(9): 1389-97, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26887333

RESUMO

BACKGROUND: Gait and akinesia deterioration in PD patients during the immediate postoperative period of DBS has been directly related to stimulation in the subthalamic region. The underlying mechanisms remain poorly understood. The aim of the present study was to clinically and anatomically describe this side effect. METHODS: PD patients presenting with a worsening of gait and/or akinesia following STN-DBS, that was reversible on stimulation arrest were included. The evaluation included (1) a Stand Walk Sit Test during a monopolar survey of each electrode in the on-drug condition; (2) a 5-condition test with the following conditions: off-drug/off-DBS, off-drug/on-best-compromise-DBS, on-drug/off-DBS, on-drug/on-best-compromise-DBS, and on-drug/on-worsening-DBS, which utilized the contact inducing the most prominent gait deterioration. The following scales were performed: UPDRSIII subscores, Stand Walk Sit Test, and dyskinesia and freezing of gait scales. Localization of contacts was performed using a coregistration method. RESULTS: Twelve of 17 patients underwent the complete evaluation. Stimulation of the most proximal contacts significantly slowed down the Stand Walk Sit Test. The on-drug/on-worsening-DBS condition compared with the on-drug/off-DBS condition worsened akinesia (P = 0.02), Stand Walk Sit Test (P = 0.001), freezing of gait (P = 0.02), and improved dyskinesias (P = 0.003). Compared with the off-drug/off-DBS condition, the on-drug/on-worsening-DBS condition improved rigidity (P = 0.007) and tremor (P = 0.007). Worsening contact sites were predominantly dorsal and anterior to the STN in the anterior zona incerta and Forel fields H2. CONCLUSIONS: A paradoxical deterioration of gait and akinesia is a rare side effect following STN-DBS. We propose that this may be related to misplaced contacts, and we discuss the pathophysiology and strategies to identify and manage this complication. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Dopaminérgicos/farmacologia , Discinesias/etiologia , Transtornos Neurológicos da Marcha/etiologia , Levodopa/farmacologia , Doença de Parkinson/terapia , Núcleo Subtalâmico , Adulto , Idoso , Terapia Combinada , Dopaminérgicos/administração & dosagem , Feminino , Humanos , Levodopa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico
11.
Front Neuroanat ; 10: 119, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28154527

RESUMO

The basal ganglia is part of a complex system of neuronal circuits that play a key role in the integration and execution of motor, cognitive and emotional function in the human brain. Parkinson's disease is a progressive neurological disorder of the motor circuit characterized by tremor, rigidity, and slowness of movement. Deep brain stimulation (DBS) of the subthalamic nucleus and the globus pallidus pars interna provides an efficient treatment to reduce symptoms and levodopa-induced side effects in Parkinson's disease patients. While the underlying mechanism of action of DBS is still unknown, the potential modulation of white matter tracts connecting the surgical targets has become an active area of research. With the introduction of advanced diffusion MRI acquisition sequences and sophisticated post-processing techniques, the architecture of the human brain white matter can be explored in vivo. The goal of this study is to investigate the white matter connectivity between the subthalamic nucleus and the globus pallidus. Two multi-fiber tractography methods were used to reconstruct pallido-subthalamic, subthalamo-pallidal and pyramidal fibers in five healthy subjects datasets of the Human Connectome Project. The anatomical accuracy of the tracts was assessed by four judges with expertise in neuroanatomy, functional neurosurgery, and diffusion MRI. The variability among subjects was evaluated based on the fractional anisotropy and mean diffusivity of the tracts. Both multi-fiber approaches enabled the detection of complex fiber architecture in the basal ganglia. The qualitative evaluation by experts showed that the identified tracts were in agreement with the expected anatomy. Tract-derived measurements demonstrated relatively low variability among subjects. False-negative tracts demonstrated the current limitations of both methods for clinical decision-making. Multi-fiber tractography methods combined with state-of-the-art diffusion MRI data have the potential to help identify white matter tracts connecting DBS targets in functional neurosurgery intervention.

12.
J Neurol ; 263(2): 290-298, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26568561

RESUMO

Deep brain stimulation (DBS) of the internal globus pallidus (GPi) could treat chorea in Huntington's disease patients. The objectives of this study were to evaluate the efficacy of GPi-DBS to reduce abnormal movements of three patients with Huntington's disease and assess tolerability. Three non-demented patients with severe pharmacoresistant chorea underwent bilateral GPi-DBS and were followed for 30, 24, and 12 months, respectively. Primary outcome measure was the change of the chorea and total motor scores of the Unified Huntington's Disease Rating Scale between pre- and last postoperative assessments. Secondary outcome measures were motor changes between ventral versus dorsal and between on- and off- GPi-DBS. GPi neuronal activities were analyzed and compared to those obtained in patients with Parkinson's disease. No adverse effects occurred. Chorea decreased in all patients (13, 67 and 29%) postoperatively. Total motor score decreased in patient 2 (19.6%) and moderately increased in patients 1 and 3 (17.5 and 1.7%), due to increased bradykinesia and dysarthria. Ventral was superior to dorsal GPi-DBS to control chorea. Total motor score increased dramatically off-stimulation compared to ventral GPi-DBS (70, 63 and 19%). Cognitive and psychic functions were overall unchanged. Lower mean rate and less frequent bursting activity were found in Huntington's disease compared to Parkinson's disease patients. Ventral GPi-DBS sustainably reduced chorea, but worsened bradykinesia and dysarthria. Based on these results and previous published reports, we propose to select non-demented HD patients with severe chorea, and a short disease evolution as the best candidates for GPi-DBS.


Assuntos
Estimulação Encefálica Profunda/métodos , Doença de Huntington/terapia , Adulto , Feminino , Globo Pálido/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Resultado do Tratamento
14.
Mov Disord ; 30(7): 992-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25880339

RESUMO

BACKGROUND: Myoclonus-dystonia related to epsilon-sarcoglycan gene mutations is characterized by myoclonic jerks and mild to moderate dystonia. The role of basal ganglia dysfunction in the pathogenesis is unknown. METHODS: Pallidal neuronal activity was recorded in six myoclonus-dystonia and six primary generalized dystonia patients operated on for internal globus pallidus deep brain stimulation. RESULTS: In myoclonus-dystonia patients compared with primary-dystonia patients, internal pallidum neurons showed higher burst frequency, lower mean burst, and pause durations. External pallidum neurons showed higher mean pause frequency. Oscillatory activity was present in 33% and 35% of internal pallidum neurons in myoclonus-dystonia and primary-dystonia patients, respectively, predominantly in the theta frequency band (3-8 Hz). In myoclonus-dystonia patients with more severe myoclonus, internal pallidum neurons exhibited a higher bursting activity with high intraburst frequency and lower oscillatory activity frequency. CONCLUSIONS: Myoclonus-dystonia appears to be related to specific changes in internal pallidum activity, leading to disruption in striato-pallido-thalamo-cortical circuits. © 2015 International Parkinson and Movement Disorder Society.


Assuntos
Distúrbios Distônicos/fisiopatologia , Globo Pálido/fisiopatologia , Neurônios/fisiologia , Ensaios Clínicos como Assunto , Humanos
15.
J Neurol ; 262(6): 1515-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25904205

RESUMO

Gait and balance disorders are the major source of motor disabilities in advanced forms of Parkinson's disease (PD). Low-frequency stimulation of the pedunculopontine nucleus area (PPNa-DBS) has been recently proposed to treat these symptoms with variable clinical results. To further understand the effects of PPNa-DBS on resistant gait and balance disorders, we performed a randomised double-blind cross-over study in six PD patients. Evaluation included clinical assessment of parkinsonian disability, quality of life and neurophysiological recordings of gait. Evaluations were done 1 month before, 4 and 6 months after surgery with four double-blinded conditions assessed: with and without PPNa-DBS, with and without levodopa treatment. Four patients completed the study and two patients were excluded from the final analysis because of peri-operative adverse events (haematoma, infection). Clinically, the combination of PPNa-DBS and levodopa treatment produced a significant decrease of the freezing episodes. The frequency of falls also decreased in three out of four patients. From a neurophysiological point of view, PPNa-DBS significantly improved the anticipatory postural adjustments and double-stance duration, but not the length and speed of the first step. Interestingly, step length and speed improved after surgery without PPNa-DBS, suggesting that the lesioning effect of PPNa-DBS surgery alleviates parkinsonian akinesia. Quality of life was also significantly improved with PPNa-DBS. These results suggest that PPNa-DBS could improve gait and balance disorders in well-selected PD patients. However, this treatment may be riskier than others DBS surgeries in these patients with an advanced form of PD.


Assuntos
Estimulação Encefálica Profunda/métodos , Transtornos Neurológicos da Marcha/terapia , Núcleo Tegmental Pedunculopontino/fisiologia , Equilíbrio Postural/fisiologia , Transtornos de Sensação/terapia , Idoso , Antiparasitários/uso terapêutico , Método Duplo-Cego , Feminino , Transtornos Neurológicos da Marcha/etiologia , Humanos , Imageamento Tridimensional , Levodopa/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Transtornos de Sensação/etiologia , Inquéritos e Questionários
16.
J Cogn Neurosci ; 27(6): 1215-37, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25514652

RESUMO

It is solidly established that top-down (goal-driven) and bottom-up (stimulus-driven) attention mechanisms depend on distributed cortical networks, including prefrontal and frontoparietal regions. On the other hand, it is less clear whether the BG also contribute to one or the other of these mechanisms, or to both. The current study was principally undertaken to clarify this issue. Parkinson disease (PD), a neurodegenerative disorder primarily affecting the BG, has proven to be an effective model for investigating the contribution of the BG to different brain functions; therefore, we set out to investigate deficits of top-down and bottom-up attention in a selected cohort of PD patients. With this objective in mind, we compared the performance on three computerized tasks of two groups of 12 parkinsonian patients (assessed without any treatment), one otherwise pharmacologically treated and the other also surgically treated, with that of a group of controls. The main behavioral tool for our study was an attentional capture task, which enabled us to tap the competition between top-down and bottom-up mechanisms of visual attention. This task was suitably combined with a choice RT and a simple RT task to isolate any specific deficit of attention from deficits in motor response selection and initiation. In the two groups of patients, we found an equivalent increase of attentional capture but also comparable delays in target selection in the absence of any salient distractor (reflecting impaired top-down mechanisms) and movement initiation compared with controls. In contrast, motor response selection processes appeared to be prolonged only in the operated patients. Our results confirm that the BG are involved in both motor and cognitive domains. Specifically, damage to the BG, as it occurs in PD, leads to a distinct deficit of top-down control of visual attention, and this can account, albeit indirectly, for the enhancement of attentional capture, reflecting weakened ability of top-down mechanisms to antagonize bottom-up control.


Assuntos
Atenção/fisiologia , Gânglios da Base/fisiopatologia , Córtex Cerebral/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Percepção Visual/fisiologia , Estudos de Coortes , Computadores , Estimulação Encefálica Profunda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Testes Neuropsicológicos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/cirurgia , Tempo de Reação , Vias Visuais/fisiopatologia
17.
Cortex ; 60: 94-102, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25444578

RESUMO

We report on thalamic recordings in a patient with chronic disorder of consciousness (DOC). Implantation of central thalamic deep brain stimulation (CT-DBS) electrodes was chosen, as this treatment has been reported to display beneficial effects with respect to behavioural responsiveness in DOC. Local field potential (LFP) oscillations were recorded from central thalamic electrodes and their changes elicited by speech stimuli consisting either of familiar voices addressing the patient or unfamiliar non-addressing phrases were studied. In response to familiar-addressing speech we observed modulation of oscillatory activity in the beta and theta band within the central thalamus accompanied by an increase in thalamocortical coherence in the theta band. Furthermore, the theta phase was coupled to the amplitude of gamma locally in the thalamus. These findings indicate a local and long-range cross-frequency response which is not only indicative of the principle involvement of the central thalamus in processing emotional and cognitive information, but also point towards intact physiological functions that may serve as a marker in diagnosing DOC patients and determining novel targets and parameters concerning therapeutic efforts.


Assuntos
Ondas Encefálicas/fisiologia , Cognição/fisiologia , Transtornos da Consciência/fisiopatologia , Emoções/fisiologia , Tálamo/fisiologia , Estimulação Acústica , Potenciais de Ação/fisiologia , Mapeamento Encefálico , Transtornos da Consciência/terapia , Estimulação Encefálica Profunda , Feminino , Humanos , Pessoa de Meia-Idade
19.
Eur Neuropsychopharmacol ; 24(8): 1229-39, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24950819

RESUMO

High-frequency deep brain stimulation (DBS) represents a major stake for treatment for treatment-resistant depression (TRD). We describe a preliminary trial of DBS of two potential brain targets in chronic TRD: the nucleus accumbens (Acb) and, in the event of failure, the caudate nucleus. Patients were followed for 6 months before surgery (M0). From M1 to M5, they underwent stimulation of the Acb target. PET scans allowed us to track metabolic modifications resulting from this stimulation. The caudate target of nonresponders was stimulated between M5 and M9. Patients then entered an extension phase, in which it was possible to adapt stimulation parameters and treatments. Six patients were included and four were operated on. At M5, none of the patients were either responders or remitters, but we did observe a decrease in Hamilton Depression Rating Scale (HDRS) scores. Three patients were switched to caudate stimulation, but no improvement was observed. During the extension phase, the Acb target was stimulated for all patients, three of whom exhibited a significant response. A decrease in glucose metabolism was observed after Acb stimulation, in the posterior cingulate gyrus, left frontal lobe, superior and medial gyrus, and bilateral cerebellum. An increase in metabolism was observed in the bilateral frontal lobe (superior gyrus), left frontal lobe (medial gyrus), and right limbic lobe (anterior cingulate gyrus). The results of this trial suggest that Acb is a more promising target than the caudate. NCT01569711.


Assuntos
Núcleo Caudado/fisiologia , Cognição/fisiologia , Estimulação Encefálica Profunda/métodos , Depressão/fisiopatologia , Depressão/terapia , Núcleo Accumbens/fisiologia , Adulto , Biofísica , Núcleo Caudado/diagnóstico por imagem , Depressão/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Núcleo Accumbens/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Estudos Prospectivos
20.
Brain Connect ; 4(3): 181-92, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24575752

RESUMO

Functional brain networks are sets of cortical, subcortical, and cerebellar regions whose neuronal activities are synchronous over multiple time scales. Spatial independent component analysis (sICA) is a widespread approach that is used to identify functional networks in the human brain from functional magnetic resonance imaging (fMRI) resting-state data, and there is now a general agreement regarding the cortical regions involved in each network. It is well known that these cortical regions are preferentially connected with specific subcortical functional territories; however, subcortical components (SC) have not been observed whether in a robust or in a reproducible manner using sICA. This article presents a new method to analyze resting-state fMRI data that enables robust and reproducible association of subcortical regions with well-known patterns of cortical regions. The approach relies on the hypothesis that the time course in subcortical regions is similar to that in cortical regions belonging to the same network. First, sICA followed by hierarchical clustering is performed on cortical time series to extract group functional cortical networks. Second, these networks are complemented with related subcortical areas based on the similarity of their time courses, using an individual general linear model and a random-effect group analysis. Two independent resting-state fMRI datasets were processed, and the SC of both datasets overlapped by 69% to 99% depending on the network, showing the reproducibility and the robustness of our approach. The relationship between SC and functional cortical networks was consistent with functional territories (sensorimotor, associative, and limbic) from an immunohistochemical atlas of the basal ganglia.


Assuntos
Mapeamento Encefálico/métodos , Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Descanso/fisiologia , Adulto , Algoritmos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Vias Neurais/fisiologia , Reprodutibilidade dos Testes , Adulto Jovem
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