The study also looked at changes in gene expression—which means our DNA tells the body to produce specific proteins that then generate physical behaviors and characteristics—in the brains of mice exposed to the light stimulation. “Based on the kinds of genes that showed changes, we get further insight into what kinds of pathways are modulated by the gamma oscillations,” Tsai says. They found that treatment meant the microglia, the main immune cells in the brain, did not produce the same amount of certain inflammatory proteins that can lead to cell damage. The specific types of genes, though, were different between the different mouse models. In neurons, the treatment increased the expression of genes associated with cellular transport (which helps clear junk from the brain) and DNA repair, among others.