Light and the Brain, 1 of 2

Did you know that “light” stimulates cognitive brain activity, even in individuals who are sight-challenged? That’s the result of research from the University of Montreal and Boston’s Brigham and Women’s Hospital. Senior co-author Julie Carrier reported that light stimulates day-like brain activity, improving alertness and mood, and enhancing performance on many cognitive tasks. More surprisingly, the brain appears to still respond to light in the brains of individuals who have no conscious vision. Their study results showed that their brains could still “see,” or detect, light via a novel photoreceptor in the ganglion cell layer of the retina, different from the rods and cones signted individuals use to see. Known as intrinsically photosensitive retinal ganglion cells (ipRGCs). These specialized photoreceptors in the retina contribute to visual function in the brain even when cells in the retina responsible for normal image formation have lost their ability to receive or process light.