Researchers from University of Manchester have found how colors impact body’s internal clock in animals. This has an effect on animal’s physiology and they will adjust their behavior accordingly.
Researchers stated that the intensity of light, which is known as irradiance, changes with the rising and setting of the sun. There are also slight differences in the character of the light’s color, with light at twilight hours being bluer than during daylight hours. These colors as well the intensity of light lets the brains know what time of day or night it is.
Timothy Brown, researcher at the Faculty of Life Sciences at the University of Manchester, and the lead author of the study, said, “This is the first time that we’ve been able to test the theory that color affects the body clock in any mammal.”
For their study, the researchers exposed mice to different visual stimuli while the researchers recorded the electrical activity in the area of their brains that serves as the biological clock. They found that a significant portion of neurons in that region proved more sensitive to alterations of color. This happened particularly between yellow and blue, compared to changes in intensity.
The researchers then repeated the experiment using artificial light in which only the intensity, not the color, was cycled. They found that the mice, which are normally nocturnal animals who would become active only after dusk, became active well before then, suggesting their body clocks weren’t properly matched to the day-night cycle.
“Our study has revealed a new sensory mechanism for estimating time of day likely found in all mammals capable of color vision. What’s exciting about our research is that the same findings can be applied to humans. In theory, color could be used to manipulate our clock, which could be useful for shift workers or travelers wanting to minimize jet lag.”
The findings were published in the journal PLOS Biology.