Psychedelic drug research is coming back. But the research still faces stigma, and funding is hard to get. Stanislav Grof was one of the leading researchers on the therapeutic applications of LSD in the 1950s and '60s. He studied the effect of hallucinogens on mental disorders, including addiction. Grof tells NPR's Arun Rath, This was a tremendous deepening and acceleration of the psychotherapeutic process. Compared with the therapy in general, which mostly focuses on suppression of symptoms, here we had something that could actually get to the core of the problems." The Schedule 1 classification of LSD and other hallucinogenic substances in 1970 was a huge blow to research. But by the '90s, attitudes had begun to change. By the 2000s, a small but growing research community was picking up where Grof and others had left off. One area that showed promise was using hallucinogens to ease anxiety and depression in patients with cancer, like Erica Rex. "I was diagnosed with breast cancer, stage 2, in 2009," Rex says. "I went through the treatment, and then there are some drugs that have terrible side effects." She says she became obsessed with the possibility of her death, and it was crippling. Then Rex [was approved] for a study on the experimental drug psilocybin, an active compound in psychedelic mushrooms. In the end, she says, it helped her depression.