A new research states that our memories are cemented in the brain during the
sleep. It was reported in LiveScience. In Massachusetts Institute of Technology,
researcher Matthew Wilson thinks that this work brings closer to an
understanding of the nature of animal dreams. It gives them a clue to the role
of sleep in processing memories of past experiences.
In his previous experiments, Matthew Wilson measured activity in rats'
hippocampuses. Hippocampus is the brain's memory center while awake and
sleeping. He found that rats do form memories while awake and the rodents
replayed their memories while snoozing. It is very much similar to humans, isn't
it? It is not known whether the rats replayed the actual images.
In human dreams, a memory movie is formed by weaving together the images that
are vividly seen!! Wilson and Dayon Ji wanted to check out whether rats replay
the visuals. So they measured brain activity in visual cortex and hippocampus
while rats ran through mazes with different designs on the floors and walls. The
brain region showed specific patterns as the animals sensed their surroundings
in the maze.
The scientists measured again the brain activity when the rats are asleep. It
turned out that rats too reeled a string of images of maze-running experience.
The "exact patterns of neuron-firing" while awake also showed up during sleep.
It shows that they have similar activity, even when they are asleep, in the
brain in the visual and memory regions.
The scientists were astonished to see the same neurons that spiked during
wakeful play is also active during sleep!!
The scientists concluded that the neurons in the visual regions "talk" to those
in the hippocampus in a sort of "conversation."
It shows that naps of rats help consolidate daily experience. So here we see the
importance of sleep. It helps us to consolidate our thoughts. It helps us to
remember for a long time!
The research is unique in the sense that for the first time it shows that the
brain is replaying memory events in 2 locations--- the visual and memory center
at once.