News Summary

• Elizabeth Rayne - Jul 6, 2023 8:00 pm UTC Most creatures sleep, but until now, REM (rapid eye movement) sleep, the phase of sleep in which dreams occur, was thought to be exclusive to vertebrates.
• A certain pattern of brain waves known as a “sleep spindle,” which also occurs during human NREM sleep, was detected.
• What exactly a sleep spindle does is not completely known yet, though this wave pattern is thought to be associated with memory.However, about once an hour, everything changed when REM sleep set in.
• They also watched for visible changes in behavior on the outside.During NREM sleep, little activity was detected in the octopuses’ brains, and any behavioral changes were extremely subtle.
• When the team was positive that the animals were asleep, they began observations.They used local field potential (LFP) recording to observe activity in the brains of the sleeping octopuses.
• It was during this phase of sleep that the researchers saw the skin of the cephalopods change colors.Octopus color change happens at the cellular level.