Psychiatrist Roger Pitman has treated patients suffering from post-traumatic stress disorder (PTSD) and whose memories have become incapacitating. He enrolled Beatrice in a study in which trauma victims were given propranolol, a drug used to treat high blood pressure. Findings suggest that it may also weaken memory. Research indicates that the stress hormone adrenaline can affect the strength of our memories. James McGaugh demonstrates how a rat's memory is enhanced by an injection of adrenaline. McGaugh maintains that the same stress hormone strengthens memories in humans. Additional research indicates that propranolol blocks adrenaline's memory-enhancing effects in rats. Based on these findings, Pitman recruited patients for a pilot study. Catherine was one participant who had been terrified when hit by a bicyclist on a Boston street. Catherine took propranolol four times daily for 10 days. Three months later, she showed no physiological signs of PTSD. In contrast, control participants given a placebo continued to show signs of the disorder. These findings led the National Institutes of Health (NIH) to fund a larger study. But then the President's Council on Bioethics condemned the study, claiming that rewriting memory undermines our true identity. Catherine counters with this: Why should people be forced to live with horrible memories? Another concern is that the drug might be used too widely. For example, some might seek to erase their painful recall of the breakup of a relationship, or even of an embarrassing moment at a party. Such experiences, and our memories of them, may in the long run make us better people.