Dreams help you make memories

                Rapid eye movement (REM) sleep – the phase where dreams appear – plays a key role in memory formation, a new study involving mice has found. We already knew that newly acquired information is stored into different types of memories, spatial or emotional, before being consolidated or integrated. How the brain performs this process has remained unclear. When mice were in REM sleep, the researchers used light pulses to turn off their memory-associated neurons to determine if it affects their memory consolidation. The next day, the rodents did not succeed in a spatial memory task learned the previous day. Silencing the same neurons for similar durations outside REM episodes had no effect on memory. This indicates that neuronal activity specifically during REM sleep is required for normal memory consolidation.