From around the age of 40 onwards, there are measurable signs that your vision is declining. Anything that can help to slow the aging process in these neuronal cells is beneficial. One critical way of slowing aging is by increasing ATP, the currency of cellular energy. So this research involves exposing groups of human volunteers of different ages to short bursts of deep red light of 670 nanometer wavelength. The researchers find that the 670 nanometer light had no impact on younger individuals but in those age 40 years and over, significant improvements were obtained.