The Brain And Sleep: 4 Effects Of Sleep Deprivation On The Brain
Many of us understand the importance of a good night’s sleep. But when our schedules extend long after work hours and the stress continues to build, finding quality sleep can seem elusive and difficult. However, just like food and water are necessary for us to function, getting enough sleep is also vital to our health.
We may not feel any immediate effects when we cut a few sleep corners. But getting up earlier and going to bed later starts to add up. And before we know it, we can experience the damaging repercussions of sleep deprivation.
Researchers have shown through multiple studies the direct connection between healthy sleep and a healthy brain. In fact, over the course of a week, getting only four hours of sleep has the same damaging effect as if we’d stayed up the entire night. And the damage isn’t reversed by a weekend of sleeping in.
1- Accumulation of toxic waste in the brain
The brain is active while we sleep, and one of the tasks it performs is emptying the toxic waste we accumulate throughout the day. This is done through the lymphatic system, a network of vessels made up of astroglial cells designed to remove insoluble proteins, such as amyloid-beta. While these proteins are deposited throughout the day, the build-up has been linked to the formation of Alzheimer’s disease and other neurodegenerative diseases. One night of sleep deprivation adds a 5% build-up of these dangerous proteins.
In addition to clearing these proteins, the glymphatic system also distributes glucose, lipids, amino acids, and neurotransmitters related to volume transmission in the brain. This is a necessary process to ensure our neurons are receiving a balanced distribution that other bodily processes may not provide throughout the day. As important as this is, our glymphatic system is primarily active while we’re asleep. That means that when we aren’t getting enough sleep, our brain is not only accumulating damaging protein build-up, it can’t properly distribute other nutrients vital to brain functionality.
2- Emotional imbalance
It’s common for us to feel cranky or irritable after a restless night. People around us can probably also attest to our more volatile moods on these days. And that’s because sleep deprivation affects the functionality of the brain’s emotional response centers.
It isn’t just that we can react negatively. Studies are uncovering that sleep deprivation leads to positive emotional fluctuations as well. Because this emotional reactivity is due to amplified activity throughout the mesolimbic reward system, our tendency to want to engage in behaviors tied with that system becomes heightened. We may crave more sugar, or want to spend more time browsing our social media feeds, seeking to flood our brain with the dopamine that isn’t being regulated.
Because of this imbalance, our brain struggles with overall executive functionality. The connections between the limbic system and the prefrontal cortex become altered in a sleep-deprived brain. The prefrontal cortex regulates the processes in our brain and sorts the stimuli so that our responses are measured and appropriate. But when we don’t get enough sleep, this regulatory function becomes dampened, leading to hypersensitivity to stimuli, prompting the limbic system to react in a heightened manner. This impacts not just our reactions, but our ability to assess information appropriately and make decisions.
3- Communication and functional delays in the brain
Anyone who has experienced a sleepless night has probably noticed a marked decline in how we react both physically and mentally the next day. That’s because lack of sleep directly impacts how our neural cells are able to communicate. Instead of the normal rapid response communication between neurons, sleep-deprived individuals have measurably slower activity.
While these effects occur throughout our brain, some areas are impacted more severely than others. Specifically, sleep deprivation makes neural activity in our temporal lobe significantly slowed, the area responsible for memory and visual perception. It becomes harder to take information or stimuli and encode it into our short-term memory stores. Sleep-deprived individuals are more likely to be forgetful, and in severe cases, these memory problems can actually become cognitive lapses where the individual has no recollection of chunks of time both immediate and long-term.
In addition, because this area also controls our visual perception, processing visual stimuli is slower as well. This can be dangerous when driving a car, for example. A sleep-deprived driver will have a delay between seeing someone step into the road or turn in front of them and being able to decide on the appropriate response action. This delay can be long enough that the driver won’t be able to respond at all, leading to accidents. In fact, sleep-deprived drivers can be just as dangerous as intoxicated drivers in this regard.
4- Limited focus and attention
When we get a good night’s sleep, we’re able to practice something known as selective attention with relative ease. We use this when we work in an open office environment and have to focus on one conversation or task while surrounded by other distractions. The more sleep-deprived our brain is, the harder it is to concentrate on complicated tasks, especially with distractions or other noticeable stimuli in our immediate area.
This happens because when we’re sleep-deprived, our brain releases a neuromodulator called adenosine. This neurotransmitter is known for its inhibitory qualities, meaning it works as a depressant to our central nervous system. Higher levels of adenosine have shown in early studies to slow down neural activity, impairing their ability to communicate appropriately. This means information processing is delayed, making it likely for distracting stimuli to break our focus and concentration.
Conclusion
We’ve all suffered from a sleepless night. And if those are the exception as opposed to the rule, our brain can bounce back. However, when we shorten our sleeping hours night after night, it becomes harder for our brain to recover and we risk long-lasting side effects. In order to avoid this, we need to understand the dangers of sleep deprivation and take steps to ensure we get the right amount of sleep every night.
