A group of researchers at the eating disorders unit at Bellvitge University hospital in Barcelona has developed a video game with built-in biofeedback that rewards emotional control in relation to anorexia. On a virtual tropical island, gamers enjoy sun and sand before experiencing stormy storms. The application is connected via Bluetooth to a single sensor that transmits heart rate and heart rate variability data heart rate from participants to the device. If participants are able to regulate their reactions and remain calm, their cardiac response is recorded by the sensor that rewards them, dispelling the storm. If they cannot regulate their emotions, the storm intensifies.