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IntroductionTaste perception is a complex phenomenon modulated by different factors, such as taste receptors and memory brain circuits. The palatability of the food, that activates the central reward pathways, also plays an important role in taste perception. It means that taste is able to influence the choice of food and then eating behaviour.ObjectivesIt is well known that people with anorexia nervosa (AN) have a lower sensitivity to reward stimuli and recent studies suggested that altered function of taste neural circuitry may contribute to restricted eating in AN.AimsThe aim of this study was to evaluate, in patients suffering from AN, the activation of brain areas involved in taste perception and in central reward mechanisms to both pleasant and aversive taste stimuli and to correlate gustatory neurocircuitry activity with eating behaviours, temperament measures and/or sensitivity to reward and to punishment.MethodsFifteen underweight female AN patients and sixteen normal-weight healthy women underwent a functional MRI to measure brain areas activation to repeated stimuli of a pleasant taste (sucrose solution), alternated with an aversive taste (bitter solution), and water taste.ResultsCompared to healthy controls, patients with AN showed a significantly reduced activation of left insula and left dorsolateral prefrontal cortex to sweet stimulus and reduced activation of right parietal cortex to bitter stimulus.ConclusionsThese results, if confirmed in future studies, may improve our knowledge about the pathophysiological mechanisms of AN.Disclosure of interestThe authors have not supplied their declaration of competing interest.

IntroductionThe functional interplay between brain hemispheres is fundamental for behavioral, cognitive and emotional control. Several pathophysiological aspects of eating disorders (EDs) have been investigated by the use of functional Magnetic Resonance Imaging (fMRI).ObjectivesThe objective of the study was to investigate functional brain asymmetry of resting-state fMRI correlations in symptomatic patients with anorexia nervosa (AN) and bulimia nervosa (BN).AimsWe aimed at revealing whether brain regions implicated in reward, cognitive control, starvation and emotion regulation show altered inter-hemispheric functional connectivity in patients with AN and BN.MethodsUsing resting-state fMRI, voxel-mirrored homotopic connectivity (VMHC) and regional inter-hemispheric spectral coherence (IHSC) analyses in two canonical slow frequency bands (“Slow-5”, “Slow-4”) were studied in 15AN and 13BN patients and 16 healthy controls (HC). Using T1-weighted and diffusion tensor imaging MRI scans, regional VMHC values were correlated with the left-right asymmetry of corresponding homotopic gray matter volumes and with the white matter callosal fractional anisotropy (FA).ResultsCompared to HC, AN patients exhibited reduced VMHC in cerebellum, insula and precuneus, while BN patients showed reduced VMHC in dorso-lateral prefrontal and orbito-frontal cortices. The regional IHSC analysis highlighted that the inter-hemispheric functional connectivity was higher in the ‘Slow-5′Band in all regions except the insula. No group differences in left-right structural asymmetries and in VMHC vs callosal FA correlations were found.ConclusionsThese anomalies indicate that AN and BN, at least in their acute phase, are associated with a loss of inter-hemispheric connectivity in regions implicated in self-referential, cognitive control and reward processing.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Introduction Taste perception is a complex phenomenon modulated by different factors, such as taste receptors and memory brain circuitry. The palatability of the food, that activates central reward pathways, also plays an important role in taste perception. It means that taste is able to influence the choice of food and then the eating behavior. Objectives It's well known that people with anorexia nervosa (AN) have lower sensitivity to reward stimuli and recent studies have shown that altered function of taste neural circuitry may contribute to restricted eating in AN. Aims The aim of this study is to evaluate, in patients suffering from AN, the activation of the brain areas involved in taste perception and in central reward mechanisms to both pleasant and aversive taste stimuli and to correlate gustatory neural circuitry activity with eating behaviors, temperament measures and/or sensitivity to reward and to punishment. Methods 12 underweight AN patients and 12 normal-weight healthy subjects underwent a functional MRI to measure brain areas activation to repeated stimuli of a pleasant taste, a sucrose solution, alternated with an aversive taste, a bitter solution, and a water taste. Results Preliminary results showed, in patients with AN, a dysfunctional activation of brain areas involved in both taste perception and reward mechanisms following both the pleasant and aversive stimulus. Conclusions These results, if confirmed in future analyses, may improve our knowledge about the pathophysiological mechanism of AN.