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A B C BOLD signal (%) BOLD signal (%) BOLD signal (%) • Hunger ra)ngs: Subjects were hungrier on the Fasted than Fed visit determined by VAS ra9ngs (6.8 ± 1.9 vs. 2.6 ± 1.8, P<0.001). • MID task performance: No significant differences in percentage of successful hits (P=0.31), nor in amount of money won between visits (P=0.65), indica9ng similar task performance. • Effect of state hunger: BOLD signal in putamen was significantly greater when Fasted than Fed during an9cipa9on of win vs. neutral trial, (P<0.05) and win vs. loss trial (P=0.01) (Fig. 4A). No significant effect of fas9ng on BOLD signal in nucleus accumbens or caudate (Fig. 4B,C). • BOLD signal in amygdala was also greater when fasted during an9cipa9on of win vs. neutral trial (P<0.05). • Statetrait interac)on of hunger on BOLD signal: TFEQHunger scores were posi9vely correlated with BOLD signal in caudate during win trial an9cipa9on when par9cipants were Fasted (r=+0.48, P=0.04), but not when Fed (r= 0.33, P=0.18; statetrait interac9on difference in slopes P=0.035) (Fig. 5). • Similar statetrait interac9on seen for BOLD signal during an9cipa9on of loss vs. neutral trial. • Confounding variables: No significant differences in menstrual cycle phase, absolute head mo9on, mood (PANAS), sleepiness, anxiety between visits. “Hungry for Money”: StateTrait Interac=ons of Hunger on Striatal Responses to An=cipatory Monetary Reward Viktoriya Nikolova 1 , Sarah N Ali 2 , Roberta Bowie 2,3 , Giuliana Durighel 2 , John McGonigle 1 , Anne LingfordHughes 1 , David J NuP 1 , E. Leigh Gibson 3 , Jimmy D Bell 2 , Anthony P Goldstone 1,2,4 1 Centre for Neuropsychopharmacology, Division of Brain Sciences, Imperial College London; 2 Metabolic and Molecular Imaging Group, MRC Clinical Sciences Centre, Imperial College London, UK; 3 Dept. of Psychology, University of Roehampton, London, UK; 4 Computa)onal, Cogni)ve and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Imperial College London, UK ACKNOWLEDGEMENTS UK Medical Research Council, Imperial College Healthcare Charity for financial support; Robert Steiner MRI Unit staff, ICCAM study collaborators at Cambridge University and Manchester University, neuroradiologist Adam Waldman for assistance. • Fas9ng increases putamen and amygdala responses to an9cipa9on of winning money. • Statetrait interac9on of hunger increases caudate responses to an9cipatory monetary reward. • Crossmodal influences of nutri9onal state and ea9ng behaviour on reward processing. • Paradigms using nonfood cues may have u9lity to study reward processing across popula9ons and pathologies including obesity. • Par)cipants: 18 healthy nonobese adults (10 male, mean ± SD age 29.6 ± 9.1 years, BMI 23.6 ± 2.9 kg/m 2 ), women scanned in follicular phase of menstrual cycle. • Procedure: Randomised crossover design with 2 visits (median 14 days apart) with func9onal MRI performed (Fig. 1): (i) aher an overnight fast 14.8 ± 1.4 hours since supper (Fasted) (ii) 70 mins aher a 1200 kCal liquid breakfast (For9sip Compact) (Fed) • Func)onal MRI Monetary Incen)ve Delay task: fMRI MID paradigm to measure BOLD signal during an9cipa9on of win or loss of hypothe9cal monetary reward using 3T Philips Achieva MR scanner and FSL analysis (Figs. 2 and 3). • Trait hunger: Subscale of Three Factor Ea9ng Ques9onnaire (TFEQ), 14 items (score range 014) [6]. • Appe=te ra=ngs: Visual Analogue Scales (10cm) including hunger. REFERENCES [1] Goldstone, A. P. et al. Am. J. Clin. Nutr. 99:131930, 2014. [2] Goldstone AP et al. Eur J Neurosci. 30:162535, 2009. [3] Carr, K. D. Physiol Behav. 91:45972, 2007. [4] Jia, Z. et al. Biol. Psychiatry 70:55360, 2011. [5] Nestor, L. et al Neuroimage 49:113343 2010 [6] Balodis, I. M. et al. Biol. Psychiatry 73:87786, 2013. [7] Stunkard, A. J., & Messick, S. J. Psycho. Res., 29:7183, 1985. [8] Provencher, V. et al. Obes. Res. 11:78392, 2003. [9] Mar9n, L. E. et al. Obesity, 18:254260, 2010. [email protected] [email protected] XYXYX • Nutri)onal state and reward: Fas9ng increases brain reward system responses to food cues, and biases appeal and ac9va9on towards energy dense foods in humans [1,2]. In rodents, nega9ve energy balance enhances consump9on and rewardseeking behaviour to drugs of abuse [3]. • Crossmodality nature of reward processing: Cocaine, alcohol and cannabis abusers show altered ac9va9on not only to drugs of abuse but also to monetary reward in the ventral striatum, caudate and putamen [4,5]. Obese (vs. healthy weight) subjects show increased ac9va9on to an9cipatory monetary reward in striatum, amygdala and thalamus [6]. • Monetary reward paradigms permit comparison across addic9ons and are not subject to individual food preferences. • Trait hunger: personality trait measuring percep9ons of intensity and frequency of hunger and associated ea9ng habits and aqtudes [7], associated with overea9ng and weight gain [8,9]. 1. Fas9ng will increase striatal ac9va9on to an9cipatory monetary reward. 2. Trait hunger scores will correlate posi9vely with striatal ac9va9on to an9cipatory monetary reward. 3. The influences of trait hunger on striatal responses to an9cipatory monetary reward will depend on state hunger (nutri9onal state). Figure 1. Study visit protocol. Timings of meals and scanning, including MID task fMRI runs and visual analogue scales. Figure 2. MID task outline. Each of 2 task runs contained 18 win, 18 loss and 18 neutral trials. Required speed of response (bu=on press) varied within runs to produce similar success rate (~60%) across sessions and subjects. Figure 3. Group average BOLD signal during win vs. neutral trial anLcipaLon phase of MID task averaged across fasted and fed visits (orange, n=18, cluster Z>2.3, P<0.05) with funcLonal ROIs overlaid in colour. Background image group average T1 scan. Coordinates in MNI space. Figure 4. BOLD signal comparison between fasted and fed visit during anLcipaLon of monetary win or loss trial in striatal fROIs. * P<0.05, ** P=0.01, paired samples ttest. INTRODUCTION RESULTS CONCLUSIONS METHODS HYPOTHESES Figure 5. Correla)ons between BOLD signal in caudate during MID task and TFEQHunger scores.
