brain research
How a sleepless night affects how we feel
© Tatyana Gladskih / Adobe Stock
Regular and sufficient sleep is essential for our health. Recent brain research studies reveal what sleep deprivation means, especially for our feelings and how we deal with them.
A while ago I went on vacation. Relatively far. I was on the plane for a good ten hours, and around twelve hours with a transfer. I took off in the afternoon around 3 p.m. and landed at my destination shortly after 7 a.m. local time the next day. Since I can’t sleep on the plane, and by that I don’t mean not, not for a second, I had already been awake for around 24 hours when I landed. When I ate dinner at 5 p.m., it had been 34 hours. I now suspect that it was mainly those 34 sleepless hours that meant I couldn’t stop crying after eating – given the beautiful landscape that surrounded me. Yes, she was beautiful. Sea, dream beach, green jungle, truly breathtaking. But I cried like a child whose teddy bear was taken away. That was not me. But an extremely sleepy version of me. Scary.
Almost all people experience an almost sleepless night every now and then, even without traveling far. Whether because of a good party or too many worries. Because of heavy, late eating or a crying baby. Life doesn’t allow us to sleep nine hours every night and so most people know from their own experience what it’s like to be tired and not well rested: we are less productive. We tend to have a bad mood. We think differently than usual. And what happens to our feelings? Neuroscientist Eti Ben-Simon from the Center for Human Sleep Science at the University of California Berkeley is addressing this question, among others.
Sleep deprivation (destroys) emotional control
Since experiments involving several days of sleep deprivation are now officially banned in the USA and many other countries with similar values and standards – due to the drastic effects on the test subjects that were observed in previous experiments and that are now known – the researcher refers to her Data from studies in which the test subjects stayed awake for one night. But they are already informative enough. Using fMRI recordings (functional magnetic resonance imaging), researchers looked at the brain activity of the test participants in certain, more or less emotionally triggering situations – once after sleep deprivation, once after a rest. For example, they showed them touching pictures of crying children as well as neutral pictures, such as train passengers.
As expected, when well rested, the scientists recorded a high level of activity in the amygdala, or to put it simply, the emotional center of our brain, with touching images, but only a low level of activity with neutral images. However, if the test subjects had spent the night before, the brain scans showed high activity in the amygdala when exposed to any type of image. That means: If we don’t have enough sleep, we are obviously easier to trigger emotionally. A harmless message can make us panic. A careless comment angry. A sad film. And the sea can break our dams of tears.
But it’s not just that the amygdala is hyperactive after sleep deprivation: the activity of the prefrontal cortex, our frontal lobe, which is significantly involved in our conscious thinking and normally regulates and controls our emotions, is significantly reduced. Hence the lower mental performance. And it’s not just the frontal lobe itself that is more sluggish: as brain scans show, the activity between the prefrontal cortex and amygdala is also much weaker than usual. The emotional control that our brain undertakes all by itself when we are healthy and well-rested is therefore significantly and disrupted in several ways when there is a lack of sleep.
Conclusion
In a blog entry for “Psychology Today”, Eti Ben-Simon points out, based on her and other recent findings, that the previously common assumption that mental illnesses such as anxiety disorders and depression caused sleep disorders should definitely be questioned: they could just as well be the result of a poor sleep routine. A night of partying or flying through the night won’t do us any lasting damage – to make up for it, we just need a good night’s sleep immediately afterwards. Chronic sleep disorders, on the other hand, i.e. long periods in which we get less than six hours of sleep per night, can definitely take a toll on us. They affect our hormonal balance, our muscle regeneration, our circulation, our thinking and feeling. It would therefore be extremely desirable for those affected to receive more helpful support from doctors, insurance companies, employers, families, etc. than advice such as “turn off the television an hour before going to bed” or “try meditation.”
Sources used: psychologytoday.com