Sleep deprivation affects many bodily functions. It will take a toll on cognition, immune function, alertness, core body temperature, and even mood. Sleepiness is thought to be a central nervous system phenomenon. Sleep deprivation is a relative concept. Common symptoms include exhaustion, a lack of physical energy, fatigue, and emotions like pessimism, stress, anger, and sadness. According to the National Sleep Foundation (NSF), your brain’s frontal cortex can only function effectively with adequate sleep. Social problems like road rage have been associated with inadequate rest. About a quarter of the adult population in America (47 million people) is sleep deprived. Below we look at how sleep deprivation affects various part of the body:
Central Nervous System
Our thoughts, actions, and emotions flow through the Central Nervous System (CNS). The CNS determines the response to stressful situations, via releasing adrenaline or cortisol. It regulates serotonin production, which controls things like sleep, desire for sex, and hunger.
Sleep facilitates the functioning of the CNS. When you are asleep, hyperactive neurons are calmed down. This way, new pathways for fresh thoughts are created. Sleep deprivation affects the creative mind, making it very difficult to understand or learn new things. Your short and long term memories are also affected, which may affect decision making and cognition. In some cases, it can result in hallucination. In extreme cases of insomnia, it could result in manic depression.
Sleep deprivation affects cognitive performance negatively, ranging from inability to pay attention and think fast, without making mistakes. It also increases stress levels. Interestingly, people tend to experience higher levels of decreased cognitive function when in a sitting position, compared to when they are in a supine position.
There has been research showing that even a night of lack of sleep or micro sleep could result in the incorporation of misinformation in events that you observe if you are sleep deprived. Other effects include cerebral shrinkage (frontal, parietal, temporal lobes), slurred speech, impaired visual sensory processing, and emotions like anger, as well as emotional volatility. You tend to focus on negative experiences, pick fights and misinterpret facial expressions. Sleep deprivation results in a disconnection between the amygdala and medial prefrontal cortex. The former processes emotions, while the latter regulates them.
Inadequate sleep has been linked to worsening depression symptoms. A significant number of people who were diagnosed with depression or anxiety slept less than 6 hours a night. Sleep disorders, especially insomnia were also linked to depression. Insomniacs were 5 times more susceptible to depression.
There is a reciprocal relationship between sleep and immunity. Evidence shows that there are detrimental effects on immune response as a result of sleep deprivation. Inadequate sleep triggers an immune system response that increases inflammation, ultimately causing tissue damage. Inflammation is linked to long-term diseases like cancer, and even heart disease.
During sleep, the body releases proteins, chemicals, and hormones – antibodies that fight off disease and cytokines. When the body is sleep deprived, these substances are not released. If your body is attacked by bacteria or viruses, the immune system is unable to fight them off, causing disease.
There is a reciprocal relationship between sleep and the respiratory system. Ventilation and respiration change when we sleep. These two processes are faster and more erratic especially during the REM, Rapid Eye Movement part of sleep. The cough reflex gets suppressed too.
Sleep loss results in impaired ventilation. This can be attributed to respiratory muscle fatigue or CNS depression. If you have lung disease, the effects of sleep deprivation on your breathing could be more adverse.
Sleep deprivation causes several digestive disorders. For instance, it decreases leptin levels in the blood. Leptin is the appetite sensor. When Leptin levels decrease, it results in binge eating and ultimately, obesity. Simultaneously, there is an increase in ghrelin, a biochemical that stimulates appetite, causing you to binge eat even more. Interestingly, higher ghrelin levels result in cravings for high fat and carbohydrate foods.
Decreased activity in the brain’s frontal lobe and increased activity in the amygdala dulls judgment and increases desire. In this state of mind, binge eating is unavoidable. The frontal lobe is responsible for decision making, while the amygdala mainly detects fear.
Studies have shown a link between obesity and sleep deprivation. Those who were sleep deprived were more susceptible to obesity, to the tunes of 30%. Sleep deprivation also increases susceptibility to diabetes. It affects how glucose is processed in the body, resulting in type 2 diabetes.
The Cardiovascular System
Cardiovascular morbidity is a common occurrence in shift workers. This has been associated with the fact that their sleep is frequently disturbed and insufficient. Research has suggested that fragmented sleep or deprivation could increase the occurrence of cardiovascular events. These events follow a circadian rhythm, resulting in sudden death, stroke in the early morning hours, and myocardial infarction.
A generally accepted hypothesis is that sleep deprivation activates the sympathetic nervous system, which results in cardiovascular events in the morning. Studies have shown that sleep deprivation also increases blood pressure (BP). For sleep loss to result in cardiovascular disease, it must occur repeatedly over a long period of time.
In a fast-paced 21st century world, where sleep is not a priority, thanks to tight work and study schedules, and free time spent on screens, it is no wonder that a quarter of the adult population is sleep deprived. Do we really understand the effect that inadequate sleep or micro sleep does to our bodies? Above, we have looked at how various parts of the body are affected by sleep deprivation. Sleep deprivation will affect the entire body, ranging from the Central Nervous System that controls our thoughts, emotions, decision making and even cognitive processes, to the immune, digestive, respiratory, and cardiovascular system. Is it a wonder that issues like road rage have become so rampant? What about lifestyle diseases?
Interestingly, all these body processes are intertwined. Cardiovascular disease for instance results when the central nervous system, immune system, respiratory system and digestive system are compromised. A seemingly simple natural fact like sleep, which is easily ignored is vital for survival. All you need to ensure that your body systems are all functional is get adequate sleep. You will have saved yourself from a lot of diseases and health problems.
Written by Laura
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