Dim Light Could Make You Dim

Working in a poorly lit office isn’t just depressing—it may actually make you dumber. In a study from Michigan State University, Nile grass rats who spent their days in dim light did not do well on spatial learning tasks and showed a 30 percent decrease in the number of dendritic spines, the connections that allow neurons to communicate. Rats who were exposed to bright light, though, improved their performance. The study’s coauthor noted that this is “similar to when people can’t find their way back to their cars after a few hours in a movie theater,” suggesting that light levels might have the same effect on us. Luckily, when the dim rats were exposed to bright light again, their brain capacity recovered fully.