China
Africa
Explore chapters and articles related to this topic
Happiness and Social Connectivity
Published in Gia Merlo, Kathy Berra, Lifestyle Nursing, 2023
The ongoing development of neuroimaging techniques over the past several decades has allowed for an emerging understanding of the neurological bases of emotion, including some of the specific neural circuits that contribute to the experience of negative and positive emotions. Presently, affect is thought to be a largely sub-neocortical process, meaning that subcortical areas of the brain are critical in the generation of emotion (Burgdorf & Panksepp, 2006). Emerging research highlights the role of the ventral striatum, a structure in the brain’s forebrain that is involved in reward pathways. For example, one study found that the interaction between ventral striatum activity and recent life stressors, after controlling for psychosocial confounds (i.e., adverse childhood events), was associated with increased positive affect. For those with low ventral striatum reactivity, greater life stress was associated with less positive affect (Nikolova et al., 2012). Positive affect has also been associated with the ability to regulate and maintain physiological processes that keep internal conditions steady (e.g., body temperature; Burgdorf & Panksepp, 2006). Thus, while several brain structures are likely involved in the experience of positive emotions, research is beginning to pinpoint the neurological processes involved in positive affect.
Distribution and Characteristics of Brain Dopamine
Published in Nira Ben-Jonathan, Dopamine, 2020
The mesolimbic dopaminergic pathway transmits DA from the VTA to the ventral striatum [10]. In histological preparations, the striatum is seen as stripes of gray and white matter and hence its name. In primates, the striatum is divided into a ventral sector, which consists of the nucleus accumbens and the olfactory tubercle, and a dorsal sector, which comprises the caudate nucleus and putamen. The major cells that populate the striatum are medium spiny GABAergic neurons that express DA receptors and are intermixed with inhibitory cholinergic interneurons. The ventral striatum, especially the nucleus accumbens, is associated with reward-related cognition, pleasure, and positive reinforcement. Dysfunctions of the mesolimbic dopaminergic system result in disorders similar to those listed above for the mesocortical system.
The Nucleus Accumbens Core and Shell: Accumbal Compartments and Their Functional Attributes
Published in Peter W. Kalivas, Charles D. Barnes, Limbic Motor Circuits and Neuropsychiatry, 2019
Ariel Y. Deutch, Andrea J. Bourdelais, Daniel S. Zahm
Data over the past decade have emphasized the role of the NAS in affective behavior. A large body of literature concerning the actions of drugs of abuse has implicated the accumbal DA innervation as critical to the hedonic properties of these drugs. These studies followed on earlier studies that indicated that the NAS was a site from which high rates of responding for electrical stimulation of the brain could be elicited. Recent electrophysiological findings indicate that the ventral striatum has neurons that respond directly to reward.208 This observation complements previous reports indicating that external stimuli, previously associated with reward, drive accumbal units.209Thus, neurons that are directly responsive to reward as well as those subserving stimulus-reward associations are present in the NAS. The latter function probably involves amygdala innervation of the NAS,210,211 (see Yim and Mogenson212) as well as a prefrontal cortical innervation of the accumbens.213,214
Neurosurgery and neuromodulation for anorexia nervosa in the 21st century: a systematic review of treatment outcomes
Published in Eating Disorders, 2022
Stuart B. Murray, Michael Strober, Reza Tadayonnejad, Ausaf A. Bari, Jamie D. Feusner
The ventral striatum consists of the nucleus accumbens and the olfactory tubercle, and is thought to be critically involved in reward processing, cognition, reinforcement learning, and motivational salience (Daniel & Pollmann, 2014). To date, one case series of six patients with an illness duration of 2–4 years examined stereotactic ablation of the ventral striatum/nucleus accumbens (Wang et al., 2013). Notably, these patients had not exhausted less invasive psychotherapeutic treatments. This case series noted a rapid increase in mean patient BMI from 13.38 (±.59) pre-operatively, to a mean BMI of 19.15 (±.1.35) at 6-month follow-up, and a mean BMI of 20.4 (±1.26) at 12-month follow-up. However, no measure of the psychological symptoms of AN was reported in this study, and it is unclear whether change in patient weight was accompanied by change in the psychological symptoms of AN.
Deep brain stimulation for treatment-resistant depression: a safe and effective option
Published in Expert Review of Neurotherapeutics, 2020
Domenico La Torre, Attilio Della Torre, Domenico Chirchiglia, Giorgio Volpentesta, Giusy Guzzi, Angelo Lavano
The ventral striatum (VS) and striatal network support goal-motivated behavior. Depression is characterized by excessive VS coupling to cognitive control and associative networks during losses versus rewards. High VS to midline cortical structure coupling may index suicidality [14]. The choice to use VC/VS as a target for depression arose from the observation of an improvement in depressive symptoms during VC/VS DBS trial for OCD. Malone et al. investigated the use of deep brain stimulation in these structures for refractory depression. They include 15 patients with chronic severe and treatment-resistant depression that received open-label DBS at three clinical sites. Electrodes were implanted bilaterally in the VC/VS region. All patients received continuous stimulation and were followed for 6 months minimum. They managed to reach significant improvements. Stimulation parameters used were maintained: frequency 127 Hz, amplitude 6.7 V, pulse width 113 µs, contact monopolar. Mean % change in MADRS and in HDRS scores was significant (55% for MADRS and 57% for HRDS) with response rates of 53% at 12 months and 71% at the last follow-up (14–67 months with an average of 37.4 months) [15].
Non-invasive brain stimulation modalities for the treatment and prevention of opioid use disorder: a systematic review of the literature
Published in Journal of Addictive Diseases, 2020
Jonathan R. Young, Shayan A. Smani, Nicholas A. Mischel, Michael D. Kritzer, Lawrence G. Appelbaum, Ashwin A. Patkar
As previously discussed, the mechanism underlying the addictive properties of substances of abuse lie in the dopamine pathways of the brain including mesolimbic projections form the ventral tegmental area to the ventral striatum.10 Continued use of drugs of abuse cause downregulation of dopamine receptors, leading to the development of tolerance and the use of progressively greater doses to achieve similar effects. Given the positive benefits of brain stimulation techniques on relapse for nicotine, alcohol, and cocaine use disorders, there may be a similar effect on relapse rates in patients undergoing maintenance for opioid use disorder. Future studies should continue to build on these successes to test such NIBS interventions within the context of maintenance treatment of OUD.