When Rachel Hope picked up the phone in 2005 to call Dr. Michael Mithoefer, she didn't have high hopes.

"I had very low expectations," said Hope, who suffered from post-traumatic stress disorder for years before investigating whether the drug Ecstasy might be able to free her from her torment. Her PTSD was traced to a period of sexual abuse as a child and a life-threatening car accident.

In the initial 45-minute conversation, Mithoefer determined that Hope didn't have other serious psychological problems. He agreed to fly her to South Carolina to take part in his study of the experimental therapy. There, she underwent more psychological testing and a physical exam. There were standard therapy sessions, so Mithoefer could understand Hope's past and her symptoms. Finally, she was ready.

Light streamed through the skylight as Hope lay back on a futon in Mithoefer's office, in the rear of a small bungalow.

On either side sat Mithoefer and his wife, Annie, a nurse.

Annie put in a CD and music started playing. As Hope placed a capsule on her tongue, they began to talk. Thirty minutes later, she began to feel deflated. Even though she had no experience with drugs, she knew: she'd been given a placebo.

True to their protocol, the Mithoefers continued the therapy, as if Hope were under the influence of MDMA. Said Hope, "We went through the process, but by the end, I'm like, 'I'm not different.'"

A week later, Mithoefer called back. He had permission to conduct MDMA sessions with test subjects who'd previously received the placebo. Would Hope like to fly back to South Carolina?

And so once again, Hope found herself on the futon, the light streaming, the music playing, the capsule on the tongue. This time, everything changed.

"It was like my whole brain was powered up like a Christmas tree, all at once," recalled Hope.

Listening to audiotapes, it isn't obvious what's happening. The conversation is fractured. But something was going on inside Hope's brain.

"Somehow, I became aware of the hardwiring decisions that my brain had made to explain why all these traumatic things happened to me, and what they meant to me about being a woman, a child living in the world, about sex, about violence," she said. "What the medicine did, it brought everything up for question."

Mithoefer said he lets patients drive the direction of the session. Typically, they alternate between talking and stretches of pure introspection. The trauma, he said, "always seems to come up."

"It's not that people just have a blissed-out experience and feel great about the world," he cautioned. "A lot of the time it's revisiting the trauma, and it's a painful, difficult experience. But the MDMA seems to make it possible for them to do it effectively."

Hope said it certainly worked for her. She estimates that 80% of her symptoms disappeared after that first MDMA-assisted session. "It allowed me to rewire my brain," she said. Another 10% of her symptoms went away over the next few weeks, she said.

According to results published last month in the Journal of Psychopharmacology, the effect was typical. Of 19 subjects in the study, more than two-thirds still showed significant improvement more than three years later -- what Mithoefer and colleagues describe as "meaningful sustained reductions" in their symptoms.

With PTSD, a common measure of severity is the so-called CAPS score, determined by answers on a detailed questionnaire. To be part of the study, patients needed a CAPS score above 50, which generally signifies moderate to severe symptoms. Hope rated a score of 86. At long-term followup, about three years after their final MDMA-aided session, only two people in the study had scores as high as 50. The CAPS score for Hope was 14.

One patient, who chose to stay anonymous, described a sense of new freedom: "I was always too frightened to look below the sadness. The MDMA and the support allowed me to pull off the controls, and I ... knew how and what and how fast or slow I needed, to see my pain."

"The question is whether this was just a flash in the plan, where people just feel good from taking a drug," said Mithoefer. "The answer to that turns out to be no, it really wasn't just a flash in the pan for most people."

For all the promise, however, 19 people is still a tiny study.

'Rebooting a computer'

Not surprisingly, there are skeptics. Dr. Edna Foa, who developed a widely used treatment for PTSD called prolonged exposure therapy, or PE, met with Mithoefer to review audiotapes of MDMA-assisted therapy. She walked away shaking her head.

"I was completely confused," Foa said. "They were all over the place. They didn't use evidence-based therapy, which would be CBT (cognitive behavioral therapy), PE or EMDR (eye movement desensitization and reprocessing). They were just kind of going with feeling. I don't know the rationale."

She was also jolted by the frequent hugs the Mithoefers gave patients at difficult points in the session. "It's very unusual," Foa chuckled. Foa said she never touches a patient "unless they ask for it. And then I hold their hand."

Mithoefer said the key feature of his approach is that it's "nondirective," in that what happens during the session is determined primarily by the individual's own process and needs. He said he often includes elements of other types of therapy -- including PE and CBT -- but that it depends on the patient's response.

Even those who see promise in MDMA-assisted treatment aren't sure how it works. "It's not well understood by any means," said Mithoefer. "We think it gives people this window of time in which they can process things without being overwhelmed by emotion, but also not being numbed up."

He said brain imaging studies, while crude, support the theory that MDMA alters hard-wired connections between conscious thought and emotional reactions -- or overreactions.

"We do know that MDMA decreases activity in the left amygdala, and increases it in the prefrontal cortex" -- brain areas associated with emotion and higher thinking, respectively, he said.

David Nichols, a professor of pharmacology at Purdue University, said no one really knows why MDMA, as well as drugs like LSD and psilocybin, have such a profound effect on the brain.

"I liken it to rebooting a computer," he said. "But when it comes to things that change the fundamental structure of personality and consciousness, and changes who you are, we don't really understand that."