Imagine being confined for at least half an hour to a dark, claustrophobic tunnel, in a machine so obnoxiously loud that it sounds like you’re in an oil drum with a jackhammer pounding on the outside. Thatʼs whatʼs involved in magnetic resonance imaging (MRI): an experience enough to make even the bravest among us flinch.

Along with answering fundamental questions about mammalian brain organization, watching interneurons’ “handshake” with other brain cells is the key to understanding autism, says Gordon Fishell.