A trip down memory's lanes.

Looks at the way scientists are mapping the paths memory takes in the brain. The findings and how they could lead to Alzheimer's drugs and brain power; Neurologists and neurobiologists breaking new ground in memory research; The roots of memory in complex biochemical and electrical brain activity; The meaning to distressing memory loss disorders and learning ability; How the brain works; Research through the years; Attitudes; Leading scientists; The prospects of research. INSET: Should we just say no to smart drugs?..