Search results for "brain stimulation"

Letter: Thalamotomy-Like Effects From Partial Removal of a Ventral Intermediate Nucleus Deep Brain Stimulator Lead in a Patient With Essential Tremor…

2017

Induced Dipoles and Possible Modulation of Wireless Effects in Implanted Electrodes. Effects of Implanting Insulated Electrodes on an Animal Test to …

2021

There is evidence that Deep Brain Stimulation (DBS) produces health benefits in patients even before initiating stimulation. Furthermore, DBS electrode insertion in rat infralimbic cortex (ILC) provokes antidepressant-like effects before stimulation, due to local inflammation and astrogliosis. Consequently, a significant effect of implanting electrodes is suspected. External fields, similar in magnitude to the brain’s endogenous fields, induce electric dipoles in conducting materials, in turn influencing neural cell growth through wireless effects. To elucidate if such dipoles influence depressive-like behavior, without external stimulation, the comparative effect of conducting and insulate…

Neuroimaging and electrophysiology meet invasive neurostimulation for causal interrogations and modulations of brain states.

2020

Deep brain stimulation (DBS) has developed over the last twenty years into a highly effective evidenced-based treatment option for neuropsychiatric disorders. Moreover, it has become a fascinating tool to provide illustrative insights into the functioning of brain networks. New anatomical and pathophysiological models of DBS action have accelerated our understanding of neurological and psychiatric disorders and brain functioning. The description of the brain networks arose through the unique ability to illustrate long-range interactions between interconnected brain regions as derived from state-of-the-art neuroimaging (structural, diffusion, and functional MRI) and the opportunity to record…

EEG and MEG primers for tracking DBS network effects

2020

Deep brain stimulation (DBS) is an effective treatment method for a range of neurological and psychiatric disorders. It involves implantation of stimulating electrodes in a precisely guided fashion into subcortical structures and, at a later stage, chronic stimulation of these structures with an implantable pulse generator. While the DBS surgery makes it possible to both record brain activity and stimulate parts of the brain that are difficult to reach with non-invasive techniques, electroencephalography (EEG) and magnetoencephalography (MEG) provide complementary information from other brain areas, which can be used to characterize brain networks targeted through DBS. This requires, howeve…

Feature selection for KNN classifier to improve accurate detection of subthalamic nucleus during deep brain stimulation surgery in Parkinson’s patien…

2017

The tremor and dystonia associated with Parkinson’s disease can be treated with deep brain stimulation (DBS) implanted into the subthalamic nucleus (STN). The accurate STN detection is a complex neurosurgeon task during a DBS surgery since a proper fixing of stimulating electrodes will impact on the patient’s future life. The brain electrical signals obtained with Micro Electrodes Register (MER) are acquired at different depths of the brain during DBS surgery to detect STN. In our previous work, we found good accuracy performance to improve the localization of STN using K-Nearest Neighbours (KNN) supervised learning algorithm. However, for real-time classification, it is essential to reduce…

Grey matter microstructural alterations in schizophrenia patients with treatment-resistant auditory verbal hallucinations.

2021

Treatment-resistant auditory verbal hallucinations (TRAVH) are a relatively prevalent and devastating symptom in patients with schizophrenia (SCZ). Even though their pathological mechanisms are poorly understood, they seem to differ from those underlying non-hallucinating SCZ.& nbsp; In this study, we characterise structural brain changes in SCZ patients with TRAVH. With respect to nonhallucinating patients and healthy controls, we studied macrostructural grey matter changes through cortical thickness and subcortical volumetric data. Additionally, we analysed microstructural differences across groups using intracortical and subcortical mean diffusivity data. This latter imaging metric has b…

The oscillatory profile induced by the anxiogenic drug fg-7142 in the amygdala-hippocampal network is reversed by infralimbic deep brain stimulation:…

2021

Anxiety and depression exhibit high comorbidity and share the alteration of the amygdala-hippocampal-prefrontal network, playing different roles in the ventral and dorsal hippocampi. Deep brain stimulation of the infralimbic cortex in rodents or the human equivalent-the subgenual cingulate cortex-constitutes a fast antidepressant treatment. The aim of this work was: (1) to describe the oscillatory profile in a rodent model of anxiety, and (2) to deepen the therapeutic basis of infralimbic deep brain stimulation in mood disorders. First, the anxiogenic drug FG-7142 was administered to anaesthetized rats to characterize neural oscillations within the amygdala and the dorsoventral axis of the …

Integration of Peripheral Adiposity Signals and Psychological Controls of Appetite

2007

Publisher Summary This chapter presents an overview of the major anatomical and neurochemical participants in brain reward circuitry. It also elaborates the evidence available to date that supports the hypothesis that energy regulatory signals can modulate food reward. Psychological modulation of feeding involves taste hedonics and preferences, and the rewarding aspects of food. The brain circuitries implicated in stimulus reward, and in the regulation of energy balance, have traditionally been considered as separate. However, more recently, accumulated evidence suggests that there is both anatomical and functional crosstalk between these sets of central nervous system (CNS) circuitry. Addi…

Gestational exposure to cocaine alters cocaine reward

2006

Exposure of the developing foetus to drugs of abuse during pregnancy may lead to persistent abnormalities of brain systems involved in drug addiction. Mice prenatally exposed to cocaine (25 mg/kg), physiological saline or non-treated during the last 7 days of pregnancy were evaluated in adulthood for the rewarding properties of cocaine (3, 25 and 50 mg/kg), using the conditioned place preference procedure. Dams treated with physiological saline gained significantly less weight over the course of gestation than controls; no other differences were observed in the maternal and offspring data. All the animals developed preference to 3 and 25 mg/kg of cocaine, but those treated prenatally with c…

STN area detection using K-NN classifiers for MER recordings in Parkinson patients during neurostimulator implant surgery

2016

Deep Brain Stimulation (DBS) applies electric pulses into the subthalamic nucleus (STN) improving tremor and other symptoms associated to Parkinson's disease. Accurate STN detection for proper location and implant of the stimulating electrodes is a complex task and surgeons are not always certain about final location. Signals from the STN acquired during DBS surgery are obtained with microelectrodes, having specific characteristics differing from other brain areas. Using supervised learning, a trained model based on previous microelectrode recordings (MER) can be obtained, being able to successfully classify the STN area for new MER signals. The K Nearest Neighbours (K-NN) algorithm has bee…