Have you ever stayed up all night and ended up feeling light-headed, high, and even a little bit drunk? Scientists are using that feeling to help people suffering from depression. A new study using mice has revealed changes in the brain that may be responsible for sleep deprivation.
For most of us, the idea of having to give up a restful night’s sleep is not fun. However, when forced to wake up due to a night shift, long trip, or last-minute study session, many people find themselves feeling surprisingly refreshed the next day. You might describe it as feeling “tired and faint,” or feeling dizzy or a little confused (but in a good way).
Scientists wonder if just one all-nighter can produce such effects, they wonder how the brain changes to affect mood, and how some antidepressants, such as ketamine, work. The authors reasoned that it may be possible to gain a deeper understanding of how the effects of this drug can be rapidly exerted.
“Interestingly, the changes in mood state following acute sleep deprivation, as I and many others have experienced, are very real, even in healthy subjects,” says North. “Sleep deprivation is the key to sleep deprivation.be statement. “However, the precise mechanisms in the brain that cause these effects are still poorly understood.”
To learn more, Wu and his team conducted experiments on healthy adult mice. They devised a system that uses an enclosure with a raised platform on slowly rotating beams to keep the animals awake while minimizing the amount of stress they undergo. The mouse could lounge on the platform or explore below, but had to keep moving out of the way of the beam. The authors tested the device and found that mice kept in it slept significantly less time.
After a night of sleep deprivation, the authors observed that the mice became more aggressive and hypersexual. Who is the culprit? Dopamine: reward neurotransmitter.
Although the authors were able to confirm that dopamine signaling was increased in the animals’ brains, it was unclear whether this was specific to one region or affected the entire brain. They scrutinized four regions: the prefrontal cortex, nucleus accumbens, hypothalamus, and dorsal striatum, monitoring dopamine release and silencing them one by one.
“The antidepressant effect lasted except when dopamine inputs to the prefrontal cortex were silenced,” explained lead author Evgenia Kozorovitsky. “That means the prefrontal cortex is a clinically relevant region when looking for therapeutic targets. But it’s also important to note that recent research has shown that dopamine neurons play a very important but completely different role in the brain. It also reinforces the idea that’s being built in “They’re not this monolithic group that’s just predicting rewards.”
This point regarding therapeutic targets is important. According to the Centers for Disease Control and Prevention (CDC), depression can: 16 million Antidepressants are widely used among American adults each year. While some people think traditional antidepressants are transformative, they don’t work for everyone. serious side effects. Research is exploring the potential of new approaches such as psychedelics for the most difficult-to-treat cases, but there is always a need for improved understanding that may lead to new treatments.
However, Kozorovitsky is not recommending staying up all night as a quick fix. Organisms may have evolved this state of heightened awareness in preparation for a time when they could protect themselves from predation and other threats by delaying sleep and increasing vigilance, but over time, chronic The problems of sleep deprivation will soon begin to outweigh these benefits.
However, this is an important new avenue for researchers to continue to explore.
“We found that sleep deprivation causes powerful antidepressant effects and rewires the brain,” Kozorovitsky said. “This is an important reminder that our casual activities, like sleepless nights, can fundamentally change our brains in just a few hours.”
The research will be published in a journal neuron.