Institution: | 1. School of Medicine, Universidade Federal do Rio Grande do Sul, , Porto Alegre, Brazil;2. Division of Gastroenterology, Hospital de Clínicas de Porto Alegre, , Porto Alegre, Brazil;3. Division of Psychology, Hospital de Clínicas de Porto Alegre, , Porto Alegre, Brazil;4. Division of Neurology, Hospital de Clínicas de Porto Alegre, , Porto Alegre, Brazil |