Sweet and bitter taste perception in anorexia nervosa: A functional MRI study

Abstract

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.