People who use methamphetamine or cocaine on a regular basis may have differences in those brain regions that are involved in choosing between right and wrong, compared to people who don't use these drugs, according to a new study of prison inmates. "This is the first study to suggest impairments in the neural systems of moral processing in both cocaine and methamphetamine users," says lead study author Samantha Fede, a graduate student in the department of psychology at the University of New Mexico. READ MORE