Inventi Impact: Nutraceuticals

Inventi:pnc/15250/15

Poor Ability to Resist Tempting Calorie Rich Food is Linked to Altered Balance between Neural\nSystems Involved in Urge and Self-control

Background: The loss of self-control or inability to resist tempting/rewarding foods, and the development of less\nhealthful eating habits may be explained by three key neural systems: (1) a hyper-functioning striatum system\ndriven by external rewarding cues; (2) a hypo-functioning decision-making and impulse control system; and (3) an\naltered insula system involved in the translation of homeostatic and interoceptive signals into self-awareness and\nwhat may be subjectively experienced as a feeling.\nMethods: The present study examined the activity within two of these neural systems when subjects were exposed to\nimages of high-calorie versus low-calorie foods using functional magnetic resonance imaging (fMRI), and related this activity\nto dietary intake, assessed by 24-hour recall. Thirty youth (mean BMI = 23.1 kg/m2, range = 19.1 - 33.7; age =19.7 years,\nrange = 14 - 22) were scanned using fMRI while performing food-specific go/nogo tasks.\nResults: Behaviorally, participants more readily pressed a response button when go trials consisted of high-calorie food\ncues (HGo task) and less readily pressed the response button when go trials consisted of low-calorie food cues (LGo task).\nThis habitual response to high-calorie food cues was greater for individuals with higher BMI and individuals who reportedly\nconsume more high-calorie foods. Response inhibition to the high-calorie food cues was most difficult for individuals with\na higher BMI and individuals who reportedly consume more high-calorie foods. fMRI results confirmed our hypotheses that\n(1) the ââ?¬Å?habitualââ?¬Â system (right striatum) was more activated in response to high-calorie food cues during the go trials than\nlow-calorie food go trials, and its activity correlated with participantsââ?¬â?¢ BMI, as well as their consumption of high-calorie foods;\n(2) the prefrontal system was more active in nogo trials than go trials, and this activity was inversely correlated with BMI\nand high-calorie food consumption.\nConclusions: Using a cross-sectional design, our findings help increase understanding of the neural basis of oneââ?¬â?¢s loss of\nability to self-control when faced with tempting food cues. Though the design does not permit inferences regarding\nwhether the inhibitory control deficits and hyper-responsivity of reward regions are individual vulnerability factors\nfor overeating, or the results of habitual overeating.