FOR thousands of years, people have sought substances that they hoped would boost their mental powers and their stamina. Leaves, roots and fruit have been chewed, brewed and smoked in a quest to expand the mind. That search continues today, with the difference only that the shamans work in pharmaceutical laboratories rather than forests. If asked why, the shamans reply that they are looking for drugs to treat the effects of Alzheimer's disease, attention-deficit disorder, strokes, and the dementias associated with Parkinson's disease and schizophrenia—and that is the truth. But by creating compounds that benefit the sick, they are offering a mental boost to the healthy, too.

Such drugs are known as cognition enhancers. They work on the neural processes that underlie such mental activities as attention, perception, learning, memory, language, planning and decision-making, usually by altering the balance of the chemical neurotransmitters involved in these processes. This week a report* from the Academy of Medical Sciences, a British learned society, says that a large number of such brain-affecting drugs are likely to emerge over the next few decades. Sir Gabriel Horn, a researcher at Cambridge University who chaired the group that produced the report, reckons that scientists are working on more than 600 drugs for neurological disorders.  Read More...