Table 1.

Food cue reward studies in BED

Neurocognitive Domain	Author (year)	BED M/F BMI	OB Group M/F BMI	LC Group M/F BMI	BN Group M/F BMI	Neuroimaging	Task	Results	Correlations	Comments
Food Cue Reward	Karhunen et al., 2000	8F BMI 35.2±5	11F BMI 32.7±4	12F BMI 22.2±2	—	SPE CT	Food exposure task	BED group shows relative increase in frontal and prefrontal areas	Positive correlation in BED group between hunger and L rCBF
	Geliebter et al., 2006	5F BMI 32.3±5 5F BMI 22.4±1	5F BMI 33.5±7	5F BMI 21.9±1	—	fMRI	Pictorial and auditory food stimuli: binge-type foods, non- binge foods and non-food pictorial stimuli	Obese BED group shows prefrontal increase including in the precentral gyrus, OFC and inferior frontal gyrus		weight stable for 3 months no activation by non-food stimuli no conserved activation in the OB group or in the lean BED group
	Schienle et al., 2009	17F 32.2±4	17F (OW) 31.6±4.7	19F 21.7±1. 4	14F 22.1±2. 5	fMRI	Pictorial food stimuli: passive viewing of high-caloric pictures, disgust items, neutral items	mOFC increase in BED relative to other groups	Positive correlation between BAS and OFC/ACC activity
	Weygandt et al., 2012	17F BMI 32.2±4	17F (OW) BMI 31.6±4.7	19F BMI 21.7±1. 4	14F BMI 22.1±2. 5	fMRI deco ding analy sis	Pictorial food stimuli: passive viewing of high-caloric pictures, disgust items, neutral items	Ensemble classifier demonstrated that L insula separated BED patients from LC Right ventral striatum provided diagnostic accuracy between BED and OB groups Left ventral striatum distinguished BED from BN groups		Reanalysis of Schienle et al., 2009
	Filbey et al., 2012	12M 14F BMI 32.72±6	—	—	—	fMR I	Gustatory personalized high-calorie cue exposure task e.g. Pepsi, chocolate milk, cream soda	Relative to water, high-calorie tastes produced greater activity in reward- processing areas including OFC, VTA, striatum and insula	BES scores correlated with hippocampal, insula and putamen activity Ventral striatum activity correlated with OFC and dorsal striatum Stronger correlations between ventral striatum and posterior cingulate areas were further associated with greater binge eating symptoms	Moderate binge eating using the Binge Eating Scale (BES) No control group
	Wang et al., 2011	8F 2M 43.4±14	5F 3M 36.5±10			PET	[11]raclopri de study following 20mg MPH Food stimulation paradigm with warm food smell and taste on tongue	BED group showed greater dorsal striatum (caudate) extracellular dopamine levels during food stimulation	BES scores correlated with caudate dopamine increases during food stimulation	OB group did not demonstrate increased extracellular dopamine levels in the striatum during food stimulation.

BED=binge eating disorder; OB= non-BED obese; LC= lean control; BN=bulimia nervosa; OW=overweight; rCBF=regional cerebral blood flow; M= Male; F= Female; SPECT=single photon emission computed tomography; fMRI=functional magnetic resonance imaging; BMI=Body Mass Index; BAS=Behavioral Activation Scale; BES=Binge Eating Scale; MPH=Methylphenidate; IFG=inferior frontal gyrus; OFC= orbitofrontal cortex; vmPFC=ventromedial prefrontal cortex; ACC=anterior cingulate cortex; mPFC=medial prefrontal cortex, L=left.