The Body's Daily Clock

This series of brain scans follows the optic nerves from the back of the eyes to the hypothalamus where they meet to form the optic chiasm. Above the chiasm, on either side of the mid-line, are 2 clusters of about 10,000 nerve cells the suprachiasmatic nuclei or SCN for short. Directly or indirectly they control all of our body's daily rhythms. They are synchronised to the light dark cycle by impulses received from the eye and conducted along the optic nerves. Brain scans courtesy of Dr Adrian Owen, MRC CBSU, Cambridge.

Back to the video index page