Doctors prescribed blood-thinning medication and forced Hershfield to quit driving, but he was still fit to practice medicine. Like many other survivors of stroke, he sometimes stuttered, and his speech became slurred. His personality also seemed to change. He suddenly became obsessed with reading and writing poetry. Soon Hershfield’s friends noticed another unusual side effect: He couldn’t stop speaking in rhyme. He finished everyday sentences with rhyming couplets, such as “Now I have to ride the bus. It’s enough to make me cuss.” And curiously, whenever he rhymed, his speech impediments disappeared.