New York: Exposure to blue light for a short period can help you make difficult decisions faster up to 40 minutes after the exposure had ended, suggests new research. "Previous studies only focused on the effects of light during the period of exposure. Our study adds to this research by showing that these beneficial effects of blue wavelength light may outlast the exposure period by over 40 minutes," said lead author Anna Alkozei, post-doctoral fellow at the University of Arizona. The results also showed that a short single exposure to blue light for half an hour is sufficient to produce measurable changes in reaction times and more efficient responses (answered more items correctly per second) during conditions of greater cognitive load after the light exposure had ended. Moreover, these improvements were directly associated with measurable changes in the activation of the prefrontal cortex, the part of the brain implicated in planning complex cognitive behaviour and decision making. "Blue-enriched white light could be used in a variety of occupational settings where alertness and quick decision making are important, such as pilot cockpits, operation rooms, or military settings,” Alkozei noted. It could also be used in settings where natural sunlight does not exist, such as the International Space Station. “Importantly, our findings suggest that using blue light before having to engage in important cognitive processes may still impact cognitive functioning for over half an hour after the exposure period ended,” Alkozei pointed out. The research abstract was published in an online supplement of the journal Sleep.