Surgeon and author Sherwin Nuland discusses the development of electroshock therapy as a cure for severe, life-threatening depression -- including his own. It’s a moving and heartfelt talk about relief, redemption and second chances.

Vilayanur Ramachandran tells us what brain damage can reveal about the connection between celebral tissue and the mind, using three startling delusions as examples.

Steven Pinker charts the decline of violence from Biblical times to the present, and argues that, though it may seem illogical and even obscene, given Iraq and Darfur, we are living in the most peaceful time in our species' existence.

Starting with the simple tale of an ant, philosopher Dan Dennett unleashes a devastating salvo of ideas, making a powerful case for the existence of memes -- concepts that are literally alive.

Bill Stone, a maverick cave explorer who has plumbed Earth’s deepest abysses, discusses his efforts to mine lunar ice for space fuel and to build an autonomous robot for studying Jupiter’s moon Europa.

Psychologist Barry Schwartz takes aim at a central tenet of western societies: freedom of choice. In Schwartz's estimation, choice has made us not freer but more paralyzed, not happier but more dissatisfied.

Dan Gilbert, author of "Stumbling on Happiness," challenges the idea that we’ll be miserable if we don’t get what we want. Our "psychological immune system" lets us feel truly happy even when things don’t go as planned.

Jeff Han shows off a cheap, scalable multi-touch and pressure-sensitive computer screen interface that may spell the end of point-and-click.

Sir Ken Robinson makes an entertaining and profoundly moving case for creating an education system that nurtures (rather than undermines) creativity.