Light governs our 'sleeping patterns'

Researchers at Johns Hopkins University have carried out the study and discovered that the eye uses light to reset the biological clock through a mechanism which is separate from the ability to see.

According to lead researcher Samer Hattar, the study's findings indicate that patients with trouble sleeping or seasonal depression can benefit from development of easier, more available tests to determine if they are able to detect light properly for functions distinct from normal sight.

"It seems that even if individuals have normal sight, they might be having a malfunction that is contributing to their inability to detect light, which can adversely affect their biological clocks," Hattar said.

In their study, the researchers genetically modified laboratory mice so that a particular set of retinal ganglion cells