In fact, different from these individuals, who underwent a similar protocol, based on the findings obtained in the present study one might hypothesise that PWS subjects, who were aware that they would have eaten chocolate in that day, and, hence, were likely to experience an intense sensorial exposure to this palatable food (T60-T70), showed an inhibited PYY secretion possibly to facilitate the ensuing ingestion of pleasurable food (i.e. chocolate) and to block an early meal termination. The gene discussed is PYY; the disease is Prader-Willi syndrome.