We now have the ability to hear another person’s thoughts. Researchers have identified the differences in brain activity linked to heard and imagined sounds, a finding that could lead to better communication devices for people who are fully paralysed.

In 2014, Brian Pasley at the University of California, Berkeley, and his colleagues eavesdropped on a person’s internal monologue for the first time . They got several people who had electrodes implanted in their brain to read text out loud while having their …