快猫短视频

SLUMBERING cats really do dream about the mice they鈥檝e just chased around the
garden, new research suggests. It seems that like people, animals have complex
dreams that reactivate experiences from earlier in the day.

鈥淥ne theory is that dreams provide the opportunity to bring together
experiences that were related but did not occur at the same time, in order to
learn from them,鈥� says Matthew Wilson at Massachusetts Institute of Technology.
鈥淭his work demonstrates that animals are capable of re-evaluating their
experiences when they are not in the midst of them.鈥�

Animals have similar sleep patterns to humans. Both involve slow wave sleep
and periods of 鈥渞apid eye movement鈥� (REM) sleep. It is during REM sleep that we
dream, reliving events or fragments of events that happened while we were awake.
But no one knew for sure if animals dreamed that way too during REM sleep.

Wilson and his colleague Kenway Louie selected four male rats, and implanted
microelectrodes into specific neurons in the hippocampus, a part of the brain
involved in memory. The rats were trained to run on a circular track and were
rewarded with food at certain checkpoints. As the rats ran, the electrodes
recorded the activity of their neurons. The running task produced very distinct
firing patterns in the hippocampus, with a particular pattern of spikes
according to where they were on the track.

The researchers continued to monitor the rats鈥� neuronal activity when they
fell asleep. During REM sleep, they recorded 45 separate episodes of activity in
the rats鈥� brains. This activity of the rats鈥� neurons during REM was compared
with the activity during the track running. The researchers looked for
correlations in both the firing patterns of individual neurons and in the time
sequence of the activity of all the neurons.

In about half the recorded sessions, sleeping rats reproduced the same brain
activity as while running on a track. And the patterns created during the
animals鈥� dreams were so close to those produced while awake that the researchers
could tell where the animal imagined it was, and whether it was dreaming of
running or just standing still. The rats replayed the memories at about the same
speed as they鈥檇 first experienced them.

快猫短视频s think that memory is consolidated in two stages, the first during
the experience itself and the second during sleep. Wilson believes that animals
may lay down long term memories during REM sleep by reactivating them. Both rats
and humans remember things better if they鈥檝e enjoyed a good night鈥檚 sleep.