NY Times [1]: Scientists have...

NY Times: Scientists have discovered a new cell in the eye responsible for resetting the biological clock. "This region, called the suprachiasmatic nucleus or SCN, is just above the optic nerve on both sides of the brain. A pinhead speck of tissue, the SCN measures the passage of every 24 hours by making and consuming proteins in precisely timed fashion - letting the body know when to wake up and when to go to sleep."