RT Journal Article SR Electronic T1 Why did the kitten cross the road? A meditation on positive versus negative reinforcement in addiction JF Journal of Psychiatry and Neuroscience JO JPN FD Canadian Medical Association SP E184 OP E185 DO 10.1503/jpn.210004 VO 46 IS 1 A1 Marco Leyton YR 2021 UL http://jpn.ca/content/46/1/E184.abstract