Our program of research cuts across the traditional boundaries of psychology, pharmacology, and neurobiology to understand processes of learning, emotion, sickness and addiction. The research is leading to a better understanding of basic neural processes involved in the modulation of the pharmacological properties of drugs, with specific applications to controlling nausea and vomiting in humans. We are currently investigating chemicals found naturally in the human body that mimic those in marijuana. These "endogenous cannabinoids," discovered in the 1990s, play a role not only in controlling nausea and vomiting, but also in learning, memory, protection against stroke and cancer, appetite, reward and addiction.