Coffee, energy drinks and exercise: Humans have seemingly thought of every trick in the book to help wake them up. However, new evidence suggests the secret to being more alert may simply have to do with the color of one's light bulbs.
The results of an experiment performed by a team of Belgian scientists suggest that exposure to different lights can impact a human's cognitive brain functions in various ways. Specifically, the study notes that a little exposure to orange light can increase a person’s brain activity and result in a boost to one’s alertness.
A team from the University of Liege began with the theory that light can be a powerful tool used to affect the brain. Researchers hypothesized the answer to better cognitive alertness was in a group of photoreceptor cells in the eyeball that control the light-sensing pigment melanopsin, which data suggest can help control the human body's internal clock. Exposure to the right kind of light can directly impact a person's ability to brush off that pesky drowsiness, they said.
In an effort to support the theory, the team put 16 human subjects through identical functional MRI scans. During these scans, scientists asked participants -- who were exposed to either a blue or orange test light -- to perform simple auditory detection and memory tasks, the study notes. Upon completion, the subjects were blindfolded for 70 minutes and then rested under a green light.
Researchers found that test subjects exposed to orange light had greater brain activity demonstrating cognitive alertness compared to those exposed to blue light. The researchers said they believe the cause of this heightened brain activity was result of the longer wavelength in orange light, which causes melanopsin to send a different signal to the brain than, say, blue or green light.
"Ultimately, these findings support the idea that the integration of light exposure over long periods of time can help optimize cognitive brain function," the article concludes.
Functionally, exposure to orange light can result in an easier ability to wake up and stay alert. Gilles Vanderwalle, one of the scientists on the Belgian team, says that more attention should be paid to the type of lighting in various environments, such as schools, according to New Scientist.
The findings of the experiment were published online in the Proceedings of the National Academy of Sciences on March 10.