Richard Sprague keeps samples of his own feces, in the family freezer, so he can send them to a Stanford University laboratory. Some days he tries to improve his sleep by swallowing potato starch to feed a certain population of microbes in his gut. Lately, he’s been studying his brain acuity every morning to see if changes in his diet can influence it.

A 52-year-old father of three and an ex-Microsoft manager who lives on Mercer Island, Sprague is a volunteer, among thousands of others, in a movement called “citizen science.” Read more at: