Previous work on modafinil has been limited to its effects on sleeping disorders like narcolepsy.

BBC: Pill to boost brain power

Never mind that Provigil, a brand name for modafinil, was not supposed to treat ADHD in the first place.

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Danielle Turner, from the Department of Psychiatry at the University of Cambridge, says modafinil could revolutionise current understanding of the way we form and retain memories.

BBC: Pill to boost brain power

"In the study, the volunteers given modafinil performed significantly better at neuropsychological tests involving short-term memory and showed less impulsive responding and an increased tendency to reflect on the tasks they were given, " she said.

BBC: Pill to boost brain power

The stock dropped after Cephalon announced that a new study had shown that its main drug, a compound called modafinil sold under the brand name Provigil, was not effective in treating Attention Deficit Hyperactivity Disorder (ADHD).

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