Researchers at UCLA and other schools are studying hallucinogenic mushrooms to determine if they have legitimate medical uses in fighting depression and physical pain

Mushrooms containing the hallucinogen psilocybin have been shown in studies to help prevent painful cluster headaches, the journal Neurology reported this summer. Another study, by Johns Hopkins researchers, said that mushrooms could help patients with mental traumas and addictions.

The chemicals in "magic" mushrooms work on some of the same neural pathways as antidepressants like Prozac. But researchers say that use of mushrooms can have unpredictable results, including the classic "bad trip."

Mushrooms were studied for their medicinal value in the 1960s, but the federal government ruled in 1970s that they had no legitimate medical use. "All research was shut down," said UCLA psychiatrist Charles S. Grob.

However, researchers were again cleared to study mushrooms in the 1990s when scientists began unraveling some of the mysteries of the brain's serotonin system, acted upon by psilocybin and other hallucinogens. Some of the latest experiments have involved giving the drug to terminal cancer patients to help them overcome their feelings of hopelessness.