Sugar pills, injections of nothing -- studies show that, more often than you'd expect, placebos really work. At TEDMED, magician Eric Mead does a trick to prove that, even when you know something's not real, you can still react as powerfully as if it is. (Warning: This talk is not suitable for viewers who are disturbed by needles or blood.)

After having obtained professional academic success in his life, Erick stops to share his experiences and his way of seeing life.

This neurological specialist explores the critical development of the teen brain, charting its astonishing process of pruning, myelination and sprouting.