Three Yale University scientists—Gary Bryson, Ph.D., Morris Bell, Ph.D., and Bruce Wexler, M.D.—randomly assigned 30 schizophrenia subjects to either a therapist-based program or a computer-based program to improve their skills in cognitive areas such as attention, memory, and executive function. Both programs essentially consisted of simplifying tasks and having subjects rehearse them. In both programs, subjects trained up to five hours a week for a 15-week period.