Optimal level of human intracranial theta activity for behavioral switching in the subthalamo-medio-prefrontal circuit.

The ability to switch between rules associating stimuli and responses depend on a circuit including the dorsomedial prefrontal cortex (dmPFC) and the subthalamic nucleus (STN). However, the precise neural implementations of switching remain unclear. To address this issue, we recorded local field potentials from the STN and from the dmPFC of neuropsychiatric patients during behavioral switching.

A single case report of STN-DBS for severe crack-cocaine dependence: double-blind ON vs. SHAM randomized controlled assessment.

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.

Somatotopic Organization of Hyperdirect Pathway Projections From the Primary Motor Cortex in the Human Brain.

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.

Deep brain stimulation of the subthalamic nucleus in obsessive-compulsives disorders: long-term follow-up of an open, prospective, observational cohort.

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.

Lesions in deep gray nuclei after severe traumatic brain injury predict neurologic outcome.

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.

Anterior pallidal deep brain stimulation for Tourette's syndrome: a randomised, double-blind, controlled trial.

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.

Acute severe depression induced by stimulation of the right globus pallidus internus.

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.

Exploration of the Connectivity between the Subthalamic Nucleus and the Globus Pallidus in the Human Brain Using Multi-Fiber Tractography.

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.

Subthalamic stimulation may inhibit the beneficial effects of levodopa on akinesia and gait.

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.

Deep brain stimulation of the internal pallidum in Huntington's disease patients: clinical outcome and neuronal firing patterns.

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.

PPNa-DBS for gait and balance disorders in Parkinson's disease: a double-blind, randomised study.

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.

Pallidal activity in myoclonus dystonia correlates with motor signs.

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.

Disentangling the Role of Cortico-Basal Ganglia Loops in Top-Down and Bottom-Up Visual Attention: An Investigation of Attention Deficits in Parkinson Disease.

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.

Modulation of central thalamic oscillations during emotional-cognitive processing in chronic disorder of consciousness.

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.

Limbic versus cognitive target for deep brain stimulation in treatment-resistant depression: accumbens more promising than caudate.

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).

Optimal target localization for subthalamic stimulation in patients with Parkinson disease.

Objective: To further determine the causes of variable outcome from deep brain stimulation of the subthalamic nucleus (DBS-STN) in patients with Parkinson disease (PD).

Methods: Data were obtained from our cohort of 309 patients with PD who underwent DBS-STN between 1996 and 2009. We examined the relationship between the 1-year motor, cognitive, and psychiatric outcomes and (1) preoperative PD clinical features, (2) MRI measures, (3) surgical procedure, and (4) locations of therapeutic contacts.

Combining spatial independent component analysis with regression to identify the subcortical components of resting-state FMRI functional networks.

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.

Can we still dream when the mind is blank? Sleep and dream mentations in auto-activation deficit.

Bilateral damage to the basal ganglia causes auto-activation deficit, a neuropsychological syndrome characterized by striking apathy, with a loss of self-driven behaviour that is partially reversible with external stimulation. Some patients with auto-activation deficit also experience a mental emptiness, which is defined as an absence of any self-reported thoughts. We asked whether this deficit in spontaneous activation of mental processing may be reversed during REM sleep, when dreaming activity is potentially elicited by bottom-up brainstem stimulation on the cortex.

Mapping cortico-striatal connectivity onto the cortical surface: a new tractography-based approach to study Huntington disease.

Huntington disease (HD) is associated with early and severe damage to the basal ganglia and particularly the striatum. We investigated cortico-striatal connectivity modifications occurring in HD patients using a novel approach which focuses on the projection of the connectivity profile of the basal ganglia onto the cortex. This approach consists in computing, for each subcortical structure, surface connectivity measures representing its strength of connections to the cortex and comparing these measures across groups.

Neuronal activity correlated with checking behaviour in the subthalamic nucleus of patients with obsessive-compulsive disorder.

Doubt, and its behavioural correlate, checking, is a normal phenomenon of human cognition that is dramatically exacerbated in obsessive-compulsive disorder. We recently showed that deep brain stimulation in the associative-limbic area of the subthalamic nucleus, a central core of the basal ganglia, improved obsessive-compulsive disorder. To understand the physiological bases of symptoms in such patients, we recorded the activity of individual neurons in the therapeutic target during surgery while subjects performed a cognitive task that gave them the possibility of unrestricted repetitive checking after they had made a choice.