The body clock enables humans and animals to synchronize the working of their body with the day and night cycle. Animal studies have revealed that the color of light has a major impact on how the brain clock measures the time of the day and on how our physiology and behavior adjust accordingly. Researchers indicated that their findings can be applied to humans too.

Lead researcher Timothy Brown from the University of Manchester in Britain said, "This is the first time that we have been able to test the theory that color affects the body clock in any mammal. So, in theory, color could be used to manipulate our clock which could be useful for shift workers or travelers wanting to minimize jet lag."

Researchers studied the change in light around dawn and dusk to analyze whether color could be used to determine the time of day. Besides the well known changes in light intensity that occur as the sun rises and sets, the researchers found that during twilight, light is reliably bluer than during the day. They next recorded electrical activity from the brain clock while mice were shown different visual stimuli. The scientists found that many of the neurons were more sensitive to changes in color between blue and yellow than to changes in brightness.