1. Department of Psychology, University of Turin, 10124 Turin, Italy
2. Division of Digestive Endoscopy, Città della Salute e della Scienza University-Hospital, 10126 Turin, Italy
3. Division of Gastroenterology, Città della Salute e della Scienza University-Hospital, 10126 Turin, Italy
4. Department of Medical Sciences, University of Turin, 10126 Turin, Italy