Getting just half a night’s sleep stops the brain's ability to write over and erase fear-related memories.
Sleep loss can take over your brain
We have already covered how sleep is crucial for our survival, even if we do not know exactly why. A new study has now shown how it can be detrimental. Getting just half a night’s sleep stops the brain's ability to write over and erase fear-related memories. This can increase your risk of conditions such as anxiety or PTSD.
The study looked at 150 adults in a sleep laboratory. These subjects were split into three categories: normal sleep, sleep restriction, and sleep-deprived. After their night of sleep, they underwent fear conditioning, in which they had to acquire and overcome fearful memories. They were shown three colors, two of which were associated with an electric shock until the two colors elicited a fear response. In the evening the scientists measured how much this conditioned response had deteriorated.
To no one's surprise, those with a full night’s sleep were able to recover from this fear conditioning the best, with strong brain activity in areas associated with emotional regulation. This was not the case for those who had half a night's sleep. These participants had the most brain activity in areas associated with fear response, and least activity in areas controlling emotion.
However, most surprising is that people who had no sleep fared much better than those who had half a night's sleep. Indeed, their brain activity was quite similar to those who had a full night’s sleep. This suggests that getting only a small amount of sleep may be worse for you - the lack of REM sleep (needed for memory consolidation) might explain this negative impact.
What does this mean for you? It should be obvious that you shouldn’t interpret these results as recommending any sleep at all. Instead, it highlights the importance of a good night’s sleep in regulating your emotional and mental health. This is particularly important for shift workers and those who regularly experience sleep deprivation or interrupted sleep patterns in their line of work.