Skip to 0 minutes and 17 secondsWhen we're awake, memories for new events are first represented as brain activity in a subcortical structure called the hippocampus. But after we fall asleep, this fresh representations are reactivated and reorganized, ready for long-term storage in the cortex. In one scientific study, the sleeping brain was shown to reproduce similar patterns of activity to those produced when individuals were learning in the preceding waking hours. This reactivation of fresh memories is thought to happen during deep sleep when the brain produces slow waves less than one per second of synchronized electrical brain activity.
Skip to 0 minutes and 57 secondsThis reorganization of the memory improves recall of the context, but also helps extract the gist of the memory, a more general form of the memory, that's easier to apply in new situations with all the unhelpful detail left out. So not having sleep is a double wami, the next day you're gonna be tired for your new learning, but also you'd have lost some of what you learnt the day before.
Sleep helps us consolidate what we have learnt during the day
When ideas are first represented in our brain while building knowledge, they are vulnerable to being lost. Research has revealed that sleep plays an important role in making these memories more permanent.
While we are awake, memories of what happens during the day are first encoded into representations in the hippocampus but, during sleeping, these fresh representations are then reactivated and reorganised as longer-lasting memories stored in our cerebral cortex.
This is illustrated strikingly by human neuroimaging studies which reveal how the sleeping brain reproduces the neural activities characterising whatever we experienced in our preceding hours of wakefulness (Maquet et al., 2000).
This reactivation of the fresh memories is thought to be achieved during deep sleep, when the brain produces slow waves (less than one per second) of synchronised electrical brain activity. The consolidation provided by sleep can improve memory of the context, but the reorganisation also involves extracting and emphasising more the basic ‘gist’ of what happened. This means the memory that is stored is more abstracted from its original context, allowing it to be recalled and used more easily in new situations.
We’d like you to work with your students to investigate this research further. How would you design a small experiment to see whether students remember their learning more after a sleep?
Share your design in the comments below.
If you conduct your experiment, we look forward to hearing what you found in the final step of this week.
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