Book Link: Why We Sleep
Two factors that decide when we want to sleep and wake up
- Signal from our internal 24 hour clock (Circadian Rhythm)
- Chemical substance that creates a “sleep pressure” (Adenosine)
Sunlight (or any other regular external signal) is used by our body to make the internal clock exactly 24 hours long. The 24 hour clock located at the center of the brain is called suprachiasmatic nucleus
Prefrontal cortex (head office of the brain) controls high-level taught and logical reasoning. This is in offline mode in night owls in early mornings due to which they cannot function on the same level as morning larks
The suprachiasmatic nucleus communicates its repeating signal of day and night using a messenger called melatonin. Melatonin signals the arrival of night darkness to our brain. Melatonin is secreted by the pineal glands located at the back of the brain
When Jet Lag occurs our body is only able to acclimate to the new time zone by one hour each day. It is easier for our body to adjust to jet lag when travelling westward than compared to travelling eastwards
Every minute in our brain a chemical called adenosine is release which helps in tracking the elapsed time since we woke up. The more this chemical increases the more the desire to sleep increases. We can artificially mute this sleep signal by using caffeine. Caffeine has a average half-life of five to seven hours.
When the enzyme in the liver fully evicts caffeine from our body it causes caffeine crash i.e. all the adenosine that could not bind to the receptors before will begin to bind to the receptors in full force.
The greater the distance between Process-C and Process-S the more sleepy we feel. When we sleep the Adenosine is slowly purged from your brain. Both these processes function independent of each other but their effects align.
Not getting sufficient sleep results in adenosine not getting drained sufficiently from our brain. Adenosine acts in a way similar to debt.
When we are asleep all our senses are still functional but once they reach our brain they are blocked by an structure called thalamus. It is the sensory gate of the brain. If the signals are sent through it is sent to the cortex where they are perceived. All the signals that are sent from our brain that initiate sleep in different parts of the body all pass through the thalamus.
When we sleep we loose external awareness and we loose our sense of time - even though we are not aware of how long we where asleep our brain still tracks time very accurately. Other phenomena that we experience when we sleep is time dilation.
Rapid Eye Movement (REM) is the stage of sleep in which we dream. During this stage the brain is as active as when we are awake. The other stage of speed is the NREM stage. The NREM stage can be further divided into 4 stages with stage 3 and 4 being much more deep than the previous 2 stages.
We experience these two stages in a 90 minute repeating pattern. The interplay between REM and NREM is necessary to remodel and update the neural circuits. This task is performed by the brain to understand which memories are important and should be preserved, which needs to be removed while reserving enough space for new memories.
NREM : Remove/ cull memories that are not important
REM : Strengthen the important memories
Awake : Fast frequency and chaotic (Reception)
NREM Sleep : Slow and very systematic wave (Reflection)
REM Sleep : Fast frequency and chaotic (Integration)
In NREM sleep wave there are spindles that occur towards the end of each wave. The more strong and frequent these spindles the more resilient the person is to external noises. In NERM sleep the various parts of our brain talk together and perform a sort of data transfer operation.
During REM sleep the thalamus opens up but instead of allowing external stimulus to enter it replays our previous experiences. In REM sleep the muscles in our body are completely relaxed we are in a paralyzed state. This is done so that we do not act out our dream.
The time of sleep required various greatly between different animals. Birds and mammals experience REM sleep while others including aquatic animals lack REM sleep. REM sleep paralysis the body which would not be possible for aquatic animals.
If we are sleep deprived for an day and then sleep properly the next day or brain will crave more of NREM sleep but the consequent days the percentage of REM sleep increases (NREM is recouped first before REM sleep). No matter how long the recovery sleep we will never come close to recovering the sleep that we lost.
Aquatic animals sleep half a brain at a time. When one half is asleep and other half is active and is response for keeping the essential bodily functions running. Birds are also able to sleep one half at a time this is to keep a lookout for prey. Humans when sleeping in an unknown environment are also show to have less deep sleep in one half of their brain. REM sleep requires both half of the brain to be asleep irrespective of the animal.
When deprived of food or in an hostile environment our body is able to delay/ reduce the amount of sleep required. Some animals like birds do this during there migration period where they have to stay away for their long flights.
We are not sleeping the way we where naturally meant to. In modern society we sleep in a monophasic manner but in olden time or in tribes untouched by electricity they sleep in a biphasic manner (7-8 hours in the night with 30-60 min sleep in the afternoon). No having biphasic sleep shortens or life span.
Among primitives humans have the shortest sleep but at the same time highest amount of REM sleep. The key have having high emotional IQ (EQ) is good amount of REM sleep. REM state sleep dreaming fuels or creativity as in REM sleep new memories are connected with older memories to create new links.
Prior to birth an human infant spends most of its time in a dream like state. There part of the brain that paralyzes the their body during REM sleep is not fully developed yet. They spend 6 hours in NREM sleep another 6 hours in REM sleep and 12 hours in an intermediate sleep state what we cannot confidently identify. Only during the final trimester does signs of wakefulness emerge (2-3 hours everyday). There is an exponential increase in REM sleep during the last 2 weeks of pregnancy (almost 9 hours) and in the last week reaches almost 12 hours. REM sleeps acts like a fertilizer for the child’s brain aiding in growth of neurological pathways. This process is called synaptogenesis.
Autism is the lack of social interaction. They do not engage with other people easily. We do not fully understand the cause of autism. But most signs indicate it occurs due to imbalance in the neural development (excess is come areas will underdeveloped in others). Children with autism have an atypical sleep cycle. They have a weaker circadian rhythm and the total amount of sleep they can generate is lesser than others. They also show a 30 to 50 deficit in REM sleep.
Alcohol consumption can inhibit the amount of REM sleep that is experienced by the infant child. It is found that the intensity of the electrical activity that occurs in the brain is also of an much lower strength (almost 200 times less intense). It is also found that the breathing rate of the infant lowers drastically when the mother was intoxicated. Alcohol is easily absorbed into an mothers milk as well. A child directly goes into REM sleep as soon as they finish sucking. But in the case of mothers that drank alcohol before breast feeding it was found the child’s sleep was more fragmented (20 to 30 % less REM sleep)
Children have a more polyphasic sleep compared to the monophasic sleep pattern that is found in adults. The reason for this is the part of the brain responsible for circadian rhythm is not developed till the third or fourth month after which it slowly starts to latch onto repeating signals. Infants have 50/50 division of NREM and REM sleep by the time they reach mid childhood it becomes 80/20 which will remain the same through early and mid adulthood.
NREM sleep plays an very important role in culling our brain and making the final refinements to fit the way we use our brain. The brain refinements start from the back or our brain during early adolescents and finish of at the frontal lob at the end. Frontal lobe is response for critical thinking and rational reasoning and this is the last aspect to reach maturity in the teenager. Sleep is not the only factor that play a role in the maturity on the brain but its an important one.
People with schizophrenia where would to have an abnormal pattern of brain maturation associated with synaptic pruning the the frontal lobe (ration reasoning and critical thinking) - being able to nether is an major symptom of schizophrenia.
The circadian rhythm of young children work on an earlier cycle hence they fail asleep early and wakeup early. During puberty this timing is pushed forward (even more than our adult parents). Older people need just as much sleep as young adults need but medicines consumed and other underlying illnesses makes it difficult to get an undisturbed full night of sleep.
As we get older and older there is an decline in the electrical quality and quantity of the deep NREM sleep (starts from our late 20s). By the time we reach your seventies we will have lost 80 to 90 % of our youthful NREM sleep.
Most of us do not have a good sense of our electrical sleep quality (because of this elders are unable to corelate there decoration in health to poor sleep - not all health issues are caused do to lack of sleep). Sleep fragmentation also increases in older age group as they wake up more frequently in the night (weakened bladder, effects of medicine, etc.). By the time we reach our eighties our sleep efficiency has fallen to 70-80% (1-1 1/2 hrs. awake every night). In older people the cardician rhythm shift’s earlier and earlier by they sleep at a later time.
Napping in the evening eases the sleep pressure which can they make it difficult to fall asleep in the evening (and then older people believe they have got insomnia). The strength of the circadian rhythm and the melatonin released also decreases when we become old. The circadian rhythm can be pushed forward in old people artificially (not exposing oneself to too much sunlight in the morning and taking one evening light as much as possible).
As people get other their brain starts detonating slow as well this process is called as atrophy. It is found that this process does not take place evenly across the brain. The middle frontal lobe (NREM/ deep sleep origin) is the region the detonates the fastest. This can explain why the quality and quantity of deep sleep in older adults decreases.
Hippocampus helps to apprehend passing memories and bind their details together. It is a long finger shaped structure tucked deep on both the side of our brain. It acts as a temporary information store for accumulating new information. Its limited in size and we try to add to much information we are at the risk of overwriting information (interference forgetting).
It was found that the sleeping restores the brains capacity for learning by making room for new memories. The sleep spindles that occurs during the deep NREM sleep helped in refreshing the brains memory. The spindles an individual experienced during sleep the more their memory refreshed. The spindles happen in a deliberate pattern between the hippocampus and our cortex (main storage) every 100 to 200 nanoseconds. This helps in transferring the information from the temporary storage to permanent storage. Older people experience much lesser sleep spindles (40% decline) causing them to have a lower learning capacity.
The concentration of sleep spindles are much more in the early morning hours. Sleeping after learning also has an positive advantage as it acts as a save button, it helps in remembering the memories that we have acquired. The more deep NREM sleep we get the more likely we are to remember things that we have learned the previous day. Sleep simulation (rocking bed, controlled pulses applied on head) applied during NREM sleep can increase the number of spindles experienced.
Sleep is able to decide which information needs to be retained and which should be deleted by using tags that we provide or using tags that are identified during sleep. This process takes place during the sleep spindles. The information from the hippocampus is passed through the frontal lobe where decision to remember or forget the memory is made before the memories to remember are sent to the cortex for permanent storage.
Skill memories (memories like walking, riding bike, etc.) are found to strengthen even without practice when we sleep. The sleep spindles in the last two hours of the late morning (the time of night with the richest spindle bursts) helped with this memory improvement. The more the increase in sleep spindles in the part of the brain that we use for learning motor skills the better the performance in the morning. Sleep spindles bathe the brain is disproportionate amount - parts that worked most with more than the others.
Sleeping for less than 6 hours causes a decrease in aerobic output, increase in lactic acid buildup, muscle strength and impairments in metabolic and other capabilities of the body. This will increase the chance of hurting ourselves. Another advantage of sleeping in increase in creativity. Our brain uses an weird algorithm that tries to seek out distant memories to create connections. This process takes place turning REM sleep.
The most immediate effect sleep deprivation is loss in concentration. Sleeping for less than 7 hours can lead to momentary lapse in concentration (micro sleep) where our eyelids closes partially or completely for a few seconds. During a microsleep we become completely oblivious to our surrounding we loose not only our vision but motor functions as well.
The recycle rate of a human being (point at which there is an noticeable decline in performance) is 16 hours. More than 7 hours of sleep is required everyday to maintain cognitive performance.
50% of truck drivers in the US are clinically obese and suffer from sleep apnea which is characterized by heavy snoring which causes chronic sleep deprivation. No amount of power naps or caffeine can replace the critical functions of sleep like memory, learning, reasoning, emotional stability. It can only help to improve our concentration that to for short period of time.
There is an small collection of people who are able to survive with no physical detonation on 6 hours of sleep. This has been attributed to an modification in their gene.
Not get proper sleep leads to us being grumpy and having very irritable mood the next day. It was found that the amygdala a structure located on both the left and right side of our brain which is associated with strong emotions like anger and rage, and linked with the fight or flight response was over active in people who have not had proper sleep. The prefrontal cortex located above our eyes which is response for reasoning, decision making and critical thinking is deeply linked with the amygdala. The cortex keeps the emotion center under control when we have had sufficient sleep. When we are sleep deprived the strong coupling between these two parts is lost.
Different deep emotional centers are located above and behind the amygdala associated with impulsivity and reward, bathed by the chemical dopamine had become hyperactive in sleep deprived people. Due to the severed linking with the cortex the emotions in sleep deprived people would swing to between these extremes.
Sleep deprivation have found have cause increased taught of suicide, depression, aggression, substance abuse, addiction and so on. Not having sufficient sleep (not getting enough NREM sleep) results in the brain in-box hippocampus not being able to absolve new information easily. The information that is retained by the brain is also not that strong and its forgotten quicker. It is found that it is difficult for the brain to make new synaptic connections when we are sleep deprived. It is also found that chronic sleep deprivation can lead to damage to the DNA that is response for memory retention and new learning.
Sleep when it comes to memory retention does not work like a bank where we can accumulate debit and pay it off later. It is an all or nothing affair.
Alzheimer’s disease is associated with the buildup of an toxic protein called beta-amyloid which aggregates in sticky clumps inside the brain. They are poisonous to neurons killing the surrounding brain cells. This protein aggregates the most in the center part of the frontal lobe the very region that is responsible for NREM sleep generation. Alzheimer’s even though effects the memory it is found to not accumulate on the hippocampus. The accumulation of amyloid on the frontal lobe causes a lose in NREM which in turn effects the brains remembering capacity.
There is a kind of sewage system in our brain called glymphatic system which is comprised of cells called glia. These cells are distributed through the entire brain and are response for the removal of the dangerous contaminants from the brain generated by the work performed by the neurons. This cells are somewhat active in the mornings but are in full force in the night during NREM sleep. This purging process is accompanied by the bathing of the brain with cerebrospinal fluid. During the night time the glia cells shrink in size which allows the cerebrospinal fluid to easily clean the toxins generated in the brain. People who sleep less in their adult life are more likely to develop Alzheimer’s disease.
Progressively slower sleep is associated with a 45% increased risk of developing and/ or dying from coronary heart disease. The cause of this is increase in blood pressure. Sleeping reduction even by a few hours is shown to have an significant increase in blood pressure. This increased pressure especially erodes the coronary nerve the nerve the feeds the heart. One cause of coronary artery blockage is atherosclerosis - fuming out of the heart corridors with the hardened plaques that contain calcium deposits.
Although the decline of the cardiovascular health due to sleep deprivation is numerous they all seem to resolve around a common culprit - sympathetic nervous system. The sympathetic nervous system is response for regulating the bodies unconscious actions. This nervous system goes into overdrive when we are in danger (fight or flight response) but this heightened state only lasts from very minutes or very hours. If it stays activated for a long time it can cause it to be maladapted. In sleep deprived people this nervous system is seen to be in an overactive state. For people with sleep disorders the sympathetic nervous system can remain in this overactive state for years.
Our heart beats faster when the sympathetic nervous system is overactive with that increases the blood pressure. In this state there is an chronic increase in a stress hormones called cortisol (alertness increasing hormone). One side effect of this hormone is the constriction of the nerves which increases the blood pressure even more. Growth hormones that help to heal the body are secreted at night. Then do not get released in sleep deprived people and our blood veins (endothelium) will start eroding and have no way of healing. This could lead to blood vessels to rapture causing heart attack or cardiac arrest. On the converse adequate sleep bathes the brain in NREM sleep and the brain releases an signal that tells the nervous system to be in a relaxed state which reduces the stress on the nervous system.
The lesser we sleep the more likely we are to eat and the more we eat the more likely we are to gain weight and become overweight. Furthermore without sufficient sleep it becomes different for our body to manage the calories that we intake and could lead to type 2 diabetes. Normally when the blood sugar or glucose level in the body increases an hormone called insulin is released which instructs the cells in the body to absorb the excess sugar. When the cells become unreactive to insulin and the sugar in our blood exceeds a certain level our body enters hyperglycemic state from where it transitions into a pre-diabetic state and finally fully blown type 2 diabetes. Lack of sleep is found to cause the cells of the body to not listen to the instructions of insulin and not absorb the excess sugar.
When we sleep less we are more likely to gain weight. One of the reasons is the imbalance of the hormones leptin and ghrelin. Leptin signals a sense of being full and ghrelin signals a sense of strong hunger. Sleep loss also increases the level of circulating endocannabinoids which is an chemical generated by the body which is similar to cannabis. These chemicals stimulates or appetite and increases the level to snack. We do not burn more calories by staying awake longer. When we are sleep deprived we seem to crave sweets, carbohydrate rich foods and salty snacks. Less effected was protein rich food, diary products and fatty foods. When we are sleep deprived the rational judgment that is made by the prefrontal cortex is hindered and the primitive deep brain structures make the decision that is more appealing.
Getting plentiful sleep also makes our gut bacteria called microbiome (enteric nervous system) happier. When the sympathetic nervous system is stressed up it causes the release of cortisol which causes bad bacteria to fester in the microbiome which will prevent the meaningful absorption of nutrients which can lead to gastrointestinal problems. If we start following a low calorie diet and sleep for shorter periods even though we will loose weight the weight loose will be because of lean body mass (muscle) which is not what we want.
For hopes of reproductive success, fitness or prowess we should get a full night of sleep. In men who slept for only 5 hours everyday for a week it was found that there testosterone levels had reduced. The men had aged by 10-15 years in there virility. Low testosterone levels can make a man feel sleepy and not be able to concentrate on tasks as this hormone has an sharpening effect on the brain. It also helps in strengthening bones and building body muscles. Women who sleep less than 6 hours have shown to have a 20% decline in follicular releasing hormone that peeks prior to ovulation and is important on conception.
Sleep fights against sickness and illness using all manners of weaponry that is available to our immune system. The killer cells, cells that are deployed by our body to fight cancerous tumor cells are also effected due to insufficient sleep. Working in night shifts and disruption in the circadian rhythm greatly increase the chance of a person getting cancer. When we do not get sufficient sleep the sympathetic nervous system stays in an aggregated state which causes an inflammatory response from the immune system. Staying in this state for an long time can cause health problems like cancer.
Cancer cells are known to use the inflammatory response to there advantage. They can lure inflammatory factors into their mases which causes blood vessels to feed them with more nutritious and oxygen. They can further mutate there DNA to become more potent. It can also the inflammatory factors to spread to other regions in the body. Sleep deprivation causes an type of microphage called M1 cells to decline which helps in combating cancer and causes the increase of another cell (M2) which helps in cancer growth.
Along with all the above effects sleep deprivation can also alter the very nature of our DNA (deoxyribonucleic acid). The genes can get altered in such a way they than increase our chance of getting an sickness. Insufficient sleep can effect the 711 gene who one half of which is revved up and the other half is in passive/ sleeping state. The one that is revved up was found to cause increase chances of cardiovascular diseases and the half that is turned down helps in maintaining metabolism and optimal immune response. Short sleep is also shown to effect the hormones that regular cholesterol. The genes that are present in the nucleolus of the cells have a shoelace like structure its tips are protected using a cap like structure called telomers. If they get damaged then our DNA ends become vulnerable and cannot operate properly. People who frequently sleep short durations have found to be much older genetically in comparison to there actual physical age.
During NREM sleep the metabolic activity in our declines but during REM sleep numerous parts of the brain begin to light up - the visuospatial regions at the back of the brain, the motor cortex that controls movement, the hippocampus and its surrounding regions the stored memories temporarily, the amygdala and the cingulate cortex an ribbon like structure that sits above the amygdala. Other regions like the brain like the left and right sides of the prefrontal cortex was shown to become less active. Dreams are not an replay of what a person has experienced by it rather focus on the emotions that the person felt during the day.
REM sleep dreaming is an form of therapy for the brain. It takes the stressful and traumatic events of the data removes the painful sting from them and provides an resolution to them in the morning. The stress related hormone noradrenaline is completely shut in the brain during REM sleep. For the REM sleep to make the emotional response from the event blunt we need dreaming that to of a specific type which is of the same emotional nature. Along with it REM sleep helps in and integrating the memory into our memory network.
People suffering from PTST are not able to forget the painful trauma from the event that took place even after sleeping and receiving REM dreaming. It was found that they have an abnormally high level of noradrenaline in their brain which prevented the threptic blunting on the emotions of the memory that is performed by REM sleep to take place and hence these patients relieved the memories with the same emotions again and again.
REM sleep also helps to tune the structures in the brain that help us to identity and understand the various emotions and expressions that are shown by people. Lack of REM sleep takes away our edge to easily distinguish between different expressions. Without getting enough REM sleep our brain shifts into an default state of negative bias where even slight unfriendly faces become menacing to us.
Deep NREM sleep strengthens ones memories. REM sleep helps in fusing and blending these memories together. Sleep inertia - the carryover of sleep state for few minutes after waking up. In REM (dream) sleep our brain becomes biased towards seeking out the most distinct nonobvious links between information. The creative thinking and problem solving skills are heightened during REM sleep. Lucid dreamers are people who are aware that they are dreaming and are able to control what they dream about.
Somnambulism - is category of sleep (somnus) disorders that involves some form of movement (ambulation). Sleep walking, talking, etc. all are symptoms of this disorder. These episodes occur during the non dreaming NREM and REM sleep (unlike what most people believe). The leading theory is that due to some reason the brain gets suck in an state between wakefulness and sleep which causes the brain to perform some actions as if they where awake. It can be inherited by children of suffers.
Insomnia is one of the most common sleep disorder (it can be inherited). It is the inability to generate sufficient sleep quantity/ quality even though the person gives themselves enough time to sleep. There are multiple types of insomnia but broadly they are classified into two types sleep onset insomnia - can’t fall asleep and sleep maintenance insomnia - can’t maintain sleep. Two most common causes of insomnia are emotional concern or worry, emotion distress or anxiety.
One of the culprits of insomnia is found to be the sympathetic nervous system being chronically in the “on” state. This causes the core temperature of the body to increase as well as the heart rate to increase. In addition the emotional center and the storage center of the brain remain active will trying to sleep in people suffering from insomnia. The thalamus (sensory gate) also remains open which needs to be closed for sleeping. Moreover ones they do fall asleep they there NREM sleep is much shallower and REM sleep more fragmented.
Narcolepsy is an neurological disorder that is related to the central nervous system. It is characterized by daytime sleepiness - sudden uncontrollable urge to sleep, sleep paralysis - not being able to move/ talk for sometime after waking up and cataplexy - sudden loose of muscle control. These cataplectic episodes can be triggered by any moderate or strong emotion - positive or negative. To control these episodes the patients have to forfeit all emotions as much as possible.
The thalamus (scope shaped) is situated on to of the brain stem (cone shaped). The brain stem is the switch that tells the thalamus to shutdown and initiate the sleep state. The on off switch that tells the brain stem initiate sleep is located near the thalamus at the center of the brain called hypothalamus. The hypothalamus releases an neurotransmitter called orexin. When orexin is released into the brain stem the switch is turned on signals the thalamus to open which signals wakefulness. In narcoleptic patients this switch can be wishy-washy state that is not on and off caused by abnormalities in the orexin. The amount of orexin generated in these patients where found to be less and the ability of the brain stem to absorb orexin was weak.
Fatal Familial Insomnia (FFI) is an rare type of insomnia that currently has no cure and will kill a patient within 10 months. It is caused by the mutation of an gene called PrNP (prion protein) which causes the protein to attack certain regions of the brain resulting in rapid brain degradation. One of the region that this protein attacks very strongly is the thalamus due to which the thalamus would be stuck in a on permanent “on” state.
We can die of sleep starvation just as quickly from food starvation. In rats total sleep deprivation where found to kill them in 15 days average. Total lack of REM sleep was just as fatal as total sleep deprivation. Total lack of NREM sleep is also deathly only it takes a way longer time (45 days).
The sleep deprived rats where found to loose weight more quicker even after being fed well and their body temperature also got colder and closer to ambient temperature (hypothermia). As mammal bodies get colder the metabolic rate of the body is increased which helps in increasing the body temperature. The skins of the rate started developing sores and wounds. There immune system was getting weaker and could not keep up with even the most normal infections. There internal organs was also greatly damaged do to the lack of sleep.
The cause of death in the rats where found to be septicemia - a toxic and systemic bacterial infection the coursed through the bloodstream and ravaged the entire body. This was an simple bacteria that is present in the rats guts that would otherwise be quelled by sleep.
The setting of the sun would signal our suprachiasmatic nucleolus its night time which would in turn cause the release of melatonin which would bring upon tiredness and eventually sleep. But with artificial lighting our 24 hour clock is tricked into thinking its not night time for an additional 2-3 hours. This was made worse with the invention of LED lights (smartphones, TVs, LED bulbs, etc.) which are the strongest in the blue spectrum of visible light which is also the spectrum which our 24 hours clock is most sensitive towards and uses to detect nighttime.
Alcohol is an type of drug that is classified as a sedative. It works by binding to the receptors in our brains and preventing them from firing. When we first ingest alcohol we feel lively this is because only the prefrontal cortex is sedated initially which is the part of the brain that helps us remain in control but as time goes on it sedates other parts of the brain as well making as well weak and loose consciousness easily. Alcohol does not induce natural sleep its effect on the brain is similar to that of a light form of anesthesia.
Alcohol disrupts our sleep additionally by fragmenting our sleep (continuous wakefulness throughout the night) and secondly blocks the generation of REM sleep. REM sleep is blocked because when the body metabolizes alcohol byproducts like aldehydes and ketones. Aldehydes block the brains ability to generate sleep. Such a long period of not getting REM sleep causes an buildup in pressure to get REM sleep which results in hallucinations, disorientation and delusions when awake (delirium tremens).
Thermal environment, especially the proximal temperature is one of the factor that determines the relative ease with which we can fall asleep. For sleep to be initialed the core body temperature has to drop be around 1℃. It is easier to fall sleep in an cold environment than in a hot environment. There is a thermosensitive cell situated in the hypothalamus right next to the 24 hours clock of our brain that tracks the drop in core temperature and signals the same to the suprachiasmatic nucleolus. Thus not only nighttime darkness but fall in the core temperature both together yet independently decide the right amount of melatonin to be released.
Most of the heat from our body is lost through the hands, feet and head (they have very densely packet nerves that are very close to the skin). This is the same reason why we put our hands and foot outside the blanket during sleep without even knowing it. A bedroom temperature of about 13.3℃ is considered ideal for sleeping.
People artificially awoken from sleep will suffer a spike in blood pressure and cause accelerated heart rates as the fight and flight nervous system will be sent into overdrive. The snooze button on alarm clocks makes this even more dangerous as the body will have to endure the same shock again and again in short intervals of time.
Sleep pills cannot induce natural sleep. There have an similar effect to alcohol they act as an sedative by targeting the higher regions of the cortex. The sleep generated by taking these pills are lacking in the largest and deepest brainwaves. In addition to these they have various side effects like daytime forgetfulness, slow reaction time, not remembering actions performed at night, grogginess etc. When people stop taking these drugs they start suffering from rebound insomnia where their insomnia is much worse than for which they started using the drug. Furthermore these pills are only shown to increase sleep slightly.
Sleep pills induced sleep makes it difficult for new memories to be formed. It is also found that people that use sleeping pills are more likely to die early (even light users) and have a higher chance to develop cancer.
Cognitive Behavioral Theory (CBT-I) is turning out to an effect first line treatment against insomnia. It includes some obvious steps such as reducing caffeine intake, sleeping in cooler room, reducing screens in bedroom, etc. alone with some steps that are specific to the user.
Physical exertion can greatly help improve sleep quality which in term will makes us more active the next day resulting in us functioning in our nominal performance. Even diet has an effect on the sleep that we get though extensive research has not been carried out but it is advised to be stay away from carbohydrate rich diet and especially sugar.
Sleep deprivation in due to work can be a serious issue. Such employees are found to be less productive, less motivated, less creative, less happy, lazy and also even unethical.
Children who slept for longer times have found to have higher memory retention which in turn results to them getting better grades. Sleep deprivation increases suicidal thoughts along with anxiety and loneliness. Almost 50% of the children diagnosed with ADHD are in fact suffering from some form of sleep disorder. The drug administered for ADHD, Adderall and Ritalin (amphetamine-based drugs) inhibit sleep making the condition of these children even worse.
There are multiple passive and active remedies we can use to counter the sleep deprivation from which we all suffer. Use smart thermostat that change the room temperature based on the persons 24 clock. Using lights that are more strong in the yellow spectrum so that the melatonin release is not inhibited in the night. We could fitness trackers to track our day to day activity and use the data to predict what will future inward appearance and inward mental and physical health look like which will keep us motivated to live a better lifestyle.
At the workspace spaces could be make to provide incentive to people who sleep 7-9 hours everyday and get the sufficient sleep on a weekly basis. Flexible work hours could be rolled out which allows an individual to work either early or into late evening depending on their preference and finally medical support (CBP-I) could be provided to people with insomnia.
The pain receptors in the brain are found to be more sensitive (almost by 42%) in people who have not received sufficient sleep. Patients in the hospital find it difficult to to sleep properly because of the new environment and the noises made by the instruments in the room. The noises that are made by these instruments are not necessary and are generally ignored by doctors. And to cure this sleep loose they are provided sleep medications. Instead of this changes can be made to remove these unnecessary noises and educate doctors on the importance of slumber in patients.