Neural Substrates Underlying Interactions between Appetite Stress and Reward

Abstract

Neurobiological mechanisms that normally control food intake and energy expenditure can be overcome by environmental cues and by stress. Of particular importance is the influence of the mesolimbic reward pathway. In genetically susceptible individuals, problematic over-eating likely reflects a changing balance in the control exerted by homeostatic versus reward circuits that are strongly influenced by environmental factors such as stress. Both stress and activation of the reward pathway have been shown to increase food intake and promote a preference for palatable, high-energy foods. Recent research has focused on the important role of circulating and central neuropeptides that powerfully regulate the brain response to food cues. For example, ghrelin has a potent positive effect on the motivational aspects of food intake, and central oxytocin may be involved in satiety. Thus, the decision to eat, or indeed to over-eat, involves a complex integrated neurobiology that includes brain centres involved in energy balance, reward and stress and their regulation by metabolic and endocrine factors.

Acute sleep deprivation increases food purchasing in men

“…Data regarding ghrelin levels was also reported in a previous paper . However, as this orexigenic peptide has a demonstrated role in the decision to consume or seek food through its action on central nervous system reward pathways , it is included here for the purpose of analyzing its relationship to our target measurement, i.e., performance on the supermarket task.…”

Association between the Oxytocin Receptor Gene Polymorphism (rs53576) and Bulimia Nervosa

“…In primitive species, the vasopressin/oxytocin‐like peptide, nematocin, provides neuromodulatory input into the gustatory plasticity circuit, as well as reproductive systems (Beets, Temmerman, Janssen, & Schoofs, ). In mammals, oxytocin is an important regulator of appetite and weight (Blevins & Ho, ; Menzies, Skibicka, Dickson, & Leng, ; Sabatier, Leng, & Menzies, ). Although peripheral mechanisms may also be involved (Blevins & Ho, ), it is thought that hypothalamic mechanisms are of key importance.…”

Peptide YY and ghrelin predict craving and risk for relapse in abstinent smokers

“…Ghrelin is expressed centrally in several areas of the brain, including the arcuate nucleus (ARC), paraventricular nucleus, and ventromedial nucleus, as well as the lateral hypothalamic area, perifornical area, and ventral tegmental area (Valassi, Scacchi, & Cavagnini, 2008; Xu, Elmquist, & Fukuda, 2011). The interaction of appetite hormones with other neuropepetides within these regions of the brain suggests their involvement in the rewarding effects of drug use (Kenny, 2011; Menzies, Skibicka, Dickson, & Leng, 2012; Volkow, Wang, Fowler, Tomasi, & Baler, 2012). …”