News Neuroscience In mice, anxiety isn’t all in the head. It can start in the heart In high-risk contexts, a racing heart can make a formerly relaxed mouse nervous In scary situations — such as being faced with a big human shoe — a mouse might behave fearfully and its heart might race. Now, scientists have used light over a mouse’s heart to make the animal behave fearfully, no big shoe required. Yaorusheng/Moment/Getty Images Plus Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Bethany