Baseline characteristics and predictors for early implantation of vagus nerve stimulation therapy in people with drug-resistant epilepsy: Observations from an international prospective outcomes registry (CORE-VNS).

Objective: Vagus nerve stimulation (VNS) Therapy is routinely indicated for people with drug-resistant epilepsy (DRE). We analyzed the baseline characteristics of individuals receiving the recently released VNS models and identified factors associated with early or late implantation.

Methods: The Comprehensive Outcomes Registry of subjects with Epilepsy (CORE-VNS), a prospective observational study evaluating the clinical and psychosocial outcomes of VNS Therapy®, is following participants for up to 60 months after VNS implantation.

Modulation of the thalamus by microburst vagus nerve stimulation: a feasibility study protocol.

Vagus nerve stimulation (VNS) was the first device-based therapy for epilepsy, having launched in 1994 in Europe and 1997 in the United States. Since then, significant advances in the understanding of the mechanism of action of VNS and the central neurocircuitry that VNS modulates have impacted how the therapy is practically implemented. However, there has been little change to VNS stimulation parameters since the late 1990s.

Pathological gambling in Parkinson's disease: subthalamic oscillations during economics decisions.

Pathological gambling develops in up to 8% of patients with Parkinson's disease. Although the pathophysiology of gambling remains unclear, several findings argue for a dysfunction in the basal ganglia circuits. To clarify the role of the subthalamic nucleus in pathological gambling, we studied its activity during economics decisions.

Deep brain electrophysiological recordings provide clues to the pathophysiology of Tourette syndrome.

Although ample evidence suggests that high-frequency deep brain stimulation (DBS) is an effective therapy in patients with Tourette syndrome (TS), its pathophysiology and the neurophysiological mechanisms underlying these benefits remain unclear. The DBS targets mainly used to date in TS are located within the basal ganglia-thalamo-cortical circuit compromised in this syndrome: the medial and ventral thalamic nuclei, which are way stations within the circuit, the globus pallidus and the nucleus accumbens. Neuronal activity can be electrophysiologically recorded from deep brain structures during DBS surgery (intraoperative microrecordings) or within few days after DBS electrode implantation (local field potentials, LFPs).

Modulating human procedural learning by cerebellar transcranial direct current stimulation.

Neuroimaging studies suggest that the cerebellum contributes to human cognitive processing, particularly procedural learning. This type of learning is often described as implicit learning and involves automatic, associative, and unintentional learning processes. Our aim was to investigate whether cerebellar transcranial direct current stimulation (tDCS) influences procedural learning as measured by the serial reaction time task (SRTT), in which subjects make speeded key press responses to visual cues.

Neurophysiology of deep brain stimulation.

We review the data concerning the neurophysiology of deep brain stimulation (DBS) in humans, especially in reference to Parkinson's disease. The electric field generated by DBS interacts with the brain in complex ways, and several variables could influence the DBS-induced biophysical and clinical effects. The neurophysiology of DBS comprises the DBS-induced effects per se as well as neurophysiological studies designed to record electrical activity directly from the basal ganglia (single-unit or local field potential) through the electrodes implanted for DBS.

Subthalamic local field potentials after seven-year deep brain stimulation in Parkinson's disease.

Studies describing subthalamic (STN) local field potentials (LFPs) recorded during deep brain stimulation (DBS) in patients with Parkinson's disease (PD), within the first month after DBS electrode implant, show that DBS modulates specific STN oscillations: whereas low-frequency (LF) oscillations (2-7 Hz) increase, beta oscillations (8-30 Hz) variably decrease. No data show whether LFPs remain stable for longer than one month after DBS surgery. Having long-term information is essential especially for use as a long-term feedback control signal for adaptive DBS systems.

The effects of levodopa and deep brain stimulation on subthalamic local field low-frequency oscillations in Parkinson's disease.

New adaptive systems for deep brain stimulation (DBS) could in the near future optimize stimulation settings online so as to achieve better control over the clinical fluctuations in Parkinson's disease (PD). Local field potentials (LFPs) recorded from the subthalamic nucleus (STN) in PD patients show that levodopa and DBS modulate STN oscillations. Because previous research has shown that levodopa and DBS variably influence beta LFP activity (8-20 Hz), we designed this study to find out how they affect low-frequency (LF) oscillations (2-7 Hz).

Cerebellum and processing of negative facial emotions: cerebellar transcranial DC stimulation specifically enhances the emotional recognition of facial anger and sadness.

Some evidence suggests that the cerebellum participates in the complex network processing emotional facial expression. To evaluate the role of the cerebellum in recognising facial expressions we delivered transcranial direct current stimulation (tDCS) over the cerebellum and prefrontal cortex. A facial emotion recognition task was administered to 21 healthy subjects before and after cerebellar tDCS; we also tested subjects with a visual attention task and a visual analogue scale (VAS) for mood.

Subthalamic local field beta oscillations during ongoing deep brain stimulation in Parkinson's disease in hyperacute and chronic phases.

In the past years, local field potential (LFP) signals recorded from the subthalamic nucleus (STN) in patients undergoing deep brain stimulation (DBS) for Parkinson's disease (PD) disclosed that DBS has a controversial effect on STN beta oscillations recorded 2-7 days after surgery for macroelectrode implantation. Nothing is known about these DBS-induced oscillatory changes 30 days after surgery. We recorded STN LFPs during ongoing DBS in 7 patients with PD, immediately (hyperacute phase) and 30 days (chronic phase) after surgery.

Increased short latency afferent inhibition after anodal transcranial direct current stimulation.

Transcranial direct current stimulation (tDCS), a technique for central neuromodulation, has been recently proposed as possible treatment in several neurological and psychiatric diseases. Although shifts on focal brain excitability have been proposed to explain the clinical effects of tDCS, how tDCS-induced functional changes influence cortical interneurones is still largely unknown. The assessment of short latency afferent inhibition (SLAI) of motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS), provides the opportunity to test non-invasively interneuronal cholinergic circuits in the human motor cortex.

Conflict-dependent dynamic of subthalamic nucleus oscillations during moral decisions.

Although lesional, neuroimaging, and brain stimulation studies have provided an insight into the neural mechanisms of judgement and decision-making, all these works focused on the cerebral cortex, without investigating the role of subcortical structures such as the basal ganglia. Besides being an effective therapeutic tool, deep brain stimulation (DBS) allows local field potential (LFP) recordings through the stimulation electrodes thus providing a physiological "window" on human subcortical structures. In this study we assessed whether subthalamic nucleus LFP oscillations are modulated by processing of moral conflictual, moral nonconflictual, and neutral statements.

The effects of levodopa and ongoing deep brain stimulation on subthalamic beta oscillations in Parkinson's disease.

Local field potentials (LFPs) recorded through electrodes implanted in the subthalamic nucleus (STN) for deep brain stimulation (DBS) in patients with Parkinson's disease (PD) show that oscillations in the beta frequency range (8-20 Hz) decrease after levodopa intake. Whether and how DBS influences the beta oscillations and whether levodopa- and DBS-induced changes interact remains unclear. We examined the combined effect of levodopa and DBS on subthalamic beta LFP oscillations, recorded in nine patients with PD under four experimental conditions: without levodopa with DBS turned off; without levodopa with DBS turned on; with levodopa with DBS turned on; and with levodopa with DBS turned off.