Brain stimulation in obesity

Abstract

Obesity is taking up epidemic proportions worldwide with significant impacts on the health of both the affected individual and on society as a whole. Treatment approaches consist of behavioural and pharmacological approaches, however, these are often found to be ineffective. In severe obesity, bariatric surgery is frequently performed. Unfortunately, 40% of patients show substantial weight gain over the long term or display the associated metabolic syndrome, making the development of novel therapies necessary. This review summarizes some of the current conceptual models, in particularly the 'food addiction' model, and then discusses specific therapeutic targets of brain stimulation, both non-invasive (transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS) and transcutaneous vagus nerve stimulation (VNS)) and invasive (deep brain stimulation and invasive VNS). As we will show, neuromodulatory approaches represent a promising tool for targeting specific brain structures implicated in the pathophysiology of obesity. Non-invasive techniques such as TMS, tDCS and transcutaneous VNS need further investigation before they may become ready for clinical usage. The currently available study data suggest that deep brain stimulation may become an effective and acceptable therapy for otherwise treatment-resistant obese patients. The results of the currently undergoing clinical trials are eagerly awaited.

Bariatric surgery in obese patients reduced resting connectivity of brain regions involved with self‐referential processing

“…Identifying neural changes after sleeve gastrectomy may provide a neurophysiological support for the development of nonoperative treatment such as brain stimulation (Goebel, Tronnier, & Muente, 2017), and minimum invasive approach to the gastric fundus, that is, bariatric embolization (Weiss & Kathait, 2017) for the large proportion of overweight individuals whose BMI do not reach the standard of bariatric surgery and even for the morbidly obese individuals. Our results showed significant reduction in cortical regions implicated in self-referential processing and interoceptive awareness along with strengthening of connectivity of these regions with cortical (DLPFC) and striatal (caudate) regions implicated in executive control/self-regulation.…”

“…Thus, these changes might underlie improvement in control of eating behavior following sleeve gastrectomy. Identifying neural changes after sleeve gastrectomy may provide a neurophysiological support for the development of nonoperative treatment such as brain stimulation (Goebel, Tronnier, & Muente, 2017), and minimum invasive approach to the gastric fundus, that is, bariatric embolization (Weiss & Kathait, 2017) for the large proportion of overweight individuals whose BMI do not reach the standard of bariatric surgery and even for the morbidly obese individuals.…”

Anatomo-Physiologic Basis for Auricular Stimulation

“…34 In addition to epilepsy and depression, researchers have proposed a clinical application for VNS and TNS for treating variety of disorders, such as migraine, 35 anxiety, 36 cognitive impairment, 37,38 Alzheimer's disease, 39 autism, 40 tinnitus, 41,42 poststroke symptoms, [43][44][45] post-traumatic stress disorder, 46 eating disorders 47 and obesity. 48 Although clinical trials on the topic are accumulating, most of them are preliminary proof-ofconcept pilot studies obtained with limited sample sizes.…”

Effect of Short-Term Transcutaneous Vagus Nerve Stimulation (tVNS) on Brain Processing of Food Cues: An Electrophysiological Study

“…Possible procedures currently include invasive approaches such as deep brain stimulation (DBS) and vagus nerve stimulation (VNS) and non-invasive options like transcranial magnetic stimulation (TMS), transcranial DC stimulation (tDCS), and transcutaneous VNS (tVNS). The scarce evidence on these techniques in the treatment of obesity has been reviewed recently (McClelland et al, 2013;Gorgulho et al, 2014;Val-Laillet et al, 2015;Göbel et al, 2017;Johnson and Wilson, 2018). Remarkable effects on food intake and body weight were shown by DBS of the hypothalamus and nucleus accumbens, regions associated with energy homeostasis and reward processing, respectively (albeit in single cases or small case series).…”