“Daniel Margoliash of University of Chicago has found evidence that young birds rehearse their new songs while sleeping. The brain cells that fire when birds make their first faltering efforts at singing show similar activity when they nap. “Birds dream of singing,” says Margoliash.
Rats, meanwhile, rehearse running in their sleep. After navigating a spiral maze all day, the rodents’ brains replay electrical signals that are characteristic of the motion throughout the night, Matthew Wilson of the Massachusetts Institute of Technology, told the meeting.”