Summary: Researchers have discovered that positive emotions enhance perceptual memories during sleep, particularly in the non-REM stage. Using mice, they found that memories linked to rewarding experiences lasted longer than neutral ones. The amygdala plays a key role in strengthening these memories by activating a tri-regional circuit with the motor and sensory cortices.

Brain recordings confirmed that this circuit reactivates during non-REM sleep, solidifying perceptual memories. Blocking amygdala signals during non-REM sleep disrupted memory retention, while blocking them during REM sleep had no effect. These findings suggest new ways to treat conditions like addiction and PTSD by targeting non-REM sleep processes.