Work in Progress:

I am a child of many cultures and religions. I grew up in a Buddhist country called Myanmar while my family followed the teachings of Islam. In my childhood memories, I saw the Buddhist monks roaming the streets in the morning to get the food donations. There was a Buddhist temple in every street filled with the sounds of the hyms to the Buddha which I naturally learned by walking past them. My father’s family followed the Sunni Islam which emphasized on orthodoxy and tradition while my mother’s family followed Sufism which focused on the arts and mysticism. Growing up it felt like the two Islamic sects were distinct religions. They had entirely different ways of praying and different interpretations of the divine. I had to learn contradictory rituals of the same religion from both sides of the family although my childish personality didn’t see the contradictions at the time. It was like learning two languages at the same time. In my teenage years, I moved to Sweden which was primarily an atheist culture. For the first time, I had to adapt to secularism where faith is no longer the center stage of social interactions. In my adult life, I moved to the UK where the faith in Protestant Christianity is stronger than in Sweden although not by much. I researched more on the Christian values because I started to see many similarities between the stories from the Bible and the Quaran. Moreover I was familiar with the Hindu customs because I have seen the Hindu festivals like Diwali and Holi near my home and my family used to watch many Bollywood movies which depicted a lot of iconography from Hinduism. I should not forget Shintoism because I personally liked watching the Japanese TV shows where there were a lot of ghosts, monsters, nature spirits and shrine maidens. All of them were inspired from the Shinto religious texts and rituals. From my life experience alone I have learned and participated in hundreds of rituals, beliefs and stories. In all those years, there was a fascinating pattern I have observed regarding how humans across the world independently came up with fantastical and mystical worlds of the afterlife beyond the mortal realm of Earth. Death was a mysterious event that could not be imagined and could not be explained. Only the Gods were immune to death for they are the spirit manifestations of the natural forces like the mountains, the sky and the seas. As well as natural diasters such as storms, volcanoes, earthquakes etc. Human-like deities with moral limitations like the Greek Pantheon were evolved later in the cultural imagination when the human society became more complex and agricultural. Then when big empires start to emerge monotheism becomes the preferred religion to dictate everyone in the empire follow one single doctrine. Since the ancient times, it was taken for granted that death was not the end of all things. The wandering soul of the newly deceased left its physical body and were transported to the mystical realms that the Gods have created in order to pass a difficult trial or to reward and punish the actions taken by the person when they were alive.

In Egyptian mythology, the god of death, Anubis judges a person’s action with a feather in balance. If the weight of their bad deeds do not exceed the weight of a feather, they will pass the test and granted access to the Fields of Reeds. If they fail, the giant serpent, Apophis emerges from the Duat underworld to devour the soul. The conceptual underpinnings of the legal system, courtroom and prison are derived from this old mythology. These mystical realms can be broadly categorized into two halves: orderly realms and chaotic realms. For those who have done good deeds in life or died an honorable death in battle, they will be chosen to reside in a realm of order. For those who have done bad deeds and caused unfair destruction, they will be thrown into a realm of chaos. In these realms, everyone is immortal unlike on the earth. Heaven and Hell are conceptions of Abrahamic religions that are inspired from mystical realms from older cultures. A heaven-like mystical realm of order is an enclosed pocket dimension where everything is beautiful and orderly. The colourful flowers, the freshwater streams, the never-ending feast, bountiful game, perfect temperature and weather, and golden structures. It is the promised land that ensures infinite happiness. They are not affected by the chaotic weather and climate systems on earth which means they exist on a different plane of existence. They are given many names: Eden in Christian mythology, The Fields of Elysium in Greek mythology, The Fields of Reeds in Egyptian mythology, Valhalla in Norse mythology, Avalon in Arthurian Legends, Paradise in Islamic mythology, Nirvana in Buddhism etc. Some of these realms are not just one plane of existence, but multiple layers on top of one another. The Gods live on the highest realm while the lower levels are occupied by the souls of descending goodness. I wonder what kind of ingenious heaven engineers were hired to build these places. Anyway, these worlds have been imagined many times independently across different cultures which hints toward an archetypal image of ideal living conditions that our species collectively remember. They are connected to how social thermoregulation is evolved in the human brain which we will see later. These heaven images are more pronounced in times of extreme stress during famine or war. We dream of a peaceful bountiful place where we can fulfill both our stomachs and our soul.

According to the Savannah hypothesis, human bodies have an unconscious preference for the savannah climate and vegetation because early humans were evolved in such an environment for millions of years. Afterwards they spread around the world in the last 100,000 years. Since the global colonization is relatively recent, our brains have not evolved fast enough to forget the savannah biome. Young infants look longer at landscape photographs of the savannah than any other biomes. Many descriptions of heaven such as an abundance of beautiful plant life, water streams, comfortable temperatures and plenty of light all point towards our universal preference for the mild climate. Everything is warm and fuzzy. Even if the heaven is located in the sky, these climatic elements are engineered into the realms. The thermal regulation system of the body is tuned to that specific climate. When we migrated throughout the world, we have invented innovative strategies and cultural techniques in order to adapt to new climates. For example, building a hut, wearing heavy clothes from animal hides and bonfire dancing rituals all help humans to live comfortably in new environments which are colder than our bodies can handle. We huddle together during times of extreme cold. Hugging and touching each other for warmth is a fundamental need to keep babies warm and safe. In other words, cultural technologies and rituals create local microclimates to accommodate our body from a harsh environment. On the other hand, the static climate of heaven is perfectly attuned to the human body at all times which is why Adam and Eve can afford to be naked in Eden. Of course, it is accidental that humans happened to evolve in the savannah climate. If we were evolved in the arctic like polar bears, we would have heavy white fur to blend in with the ice and our image of heaven would mirror the cold environment. This is a strange notion that we find it difficult to imagine. During the last ice age when the northern hemisphere was locked up in ice, the Sahara was a lush and bountiful environment filled with rich biodiversity that rivals the Amazon Rainforest. The moderate temperatures of the ancient Africa are comparable to present day Mediterranean or the Paradise Islands in the Indies. This is why those who live in the Mediterranean do not want to live anywhere else since it has the perfect climate suited for the human body. When I talked to the Italians living in London, the common complaint from them is the abhorrent British rainy weather and they cannot wait to return to their home country. It is also a coincidence that the weather of the Mediterranean region happens to mimic the temperatures that our bodies are evolved to find pleasurable. What I am trying to point out is that every animal is evolved to exploit a certain environmental and climatic niche which in turn create a feeling of pleasure in their bodies when living in that perfect niche. Heaven is a representation of the human-environmental niche in the collective imagination.

On the other hand, we appreciate life better when we explore the realms of chaos. They are the opposite of heaven. Each layer of hell creates harsh environments that are inhospitable to the human body. The eternal flames or the cold abyss. Hell could only exist in our imagination because we possess the knowledge of good and evil. Of course it is hard to define what good and evil are. But we know it when we see it. You will see later that the brain areas that judge good and evil are recycled from the same area that does thermoregulation. Good people who play fair should be rewarded. Evil people who cheat the game should be punished. It feels rewarding for good people to see cheaters and freeloaders being punished. In order to imagine eternal suffering, we must first be aware that the body is vulnerable to many physical forces. Our inherent knowledge of vulnerability leads to the design of horrible punishments. It is funny how the unique punishments in hell reflect the sadistic nature of the contemporary culture. Since the Middle Ages were especially brutal, their conception of hell has stuck in our collective imagination. One brief look at the elaborate torture devices of the middle ages will give you hints about where the inspiration came from. There is another thing that puzzles me. Which came first? The brutal nature of mortal existence or the brutal punishments of Hell. Most of life is suffering, that much is clear. Mother Nature has many ways in her arsenal that could take us out. Drowning in flood, burning in lava, or buried in ice. Not to mention disease, starvation, war, and death. Horsemen of the Apocalypse are personification of species level threats that can wipe us out. Our body could only thrive in a small range of environmental conditions which is why the weather in heaven is maintained within a narrow margin. Hell exaggerates extreme conditions in order to punish those who did not pursue a good moral life. It is easy to imagine a sea of burning lava, a desert of extreme cold, or always being hungry, being chased and eaten by a predator, being bitten by snakes, being beaten by demons. These are archetypal fears. More detailed and elaborate punishments reflect the culture’s preoccupation with creating pain. The knowledge of human vulnerability, the knowledge of one’s own nakedness is required to imagine the image of hell. If I can be hurt in this way, so can they. We use empathy to imagine how it would feel for someone to suffer a specific form of torture. Then we carry it out and see their reaction. If they feel a lot of pain, then the torture is successful. We can do that because every human possesses the same physiological architecture.

How does it feel to sense temperature? What is the concept of ‘temperature’ in the first place? Temperature is an emergent property that arises from the average velocity of the molecules in an environment. Every particle is always vibrating and moving. Some are faster than others. We can’t see the movement of each and every particle but we can sense them by how hot or cold their movement produces. If the air is hot, the air molecules are moving fast because they contain a lot of kinetic energy. If the air is cold, the air molecules are moving slowly. Only in a complete vacuum where there are no molecules, there is no such thing as temperature. It simply does not exist. A true vacuum is ultra-rare in the universe. Even in space, there are some hydrogen particles flying about albeit very sparsely. The universe is almost never 100% empty and so the elusive absolute zero has never been observed in nature. Although it is possible to reach a temperature close to absolute zero in lab conditions. Seen in this way, it is clear that life on earth must have evolved the necessary mechanisms to detect the temperature around its environment early in its existence. Living things require a moderate environment in order to carry out orderly chemical reactions necessary for homeostasis. In other words, it needs to detect the relative difference between the conditions within the cell and outside the cell. And then adjust the inner conditions accordingly. Most life on earth except for a few extremophiles has to live within a narrow range of temperatures according to the niche an organism has evolved to exploit. If it is too hot the proteins denature and the cells burst into death. If it is too cold, the chemical reactions grind to a halt. Neither outcome is desirable. So, life has evolved to control the internal temperature at a consistent rate to propagate indefinitely.

In the case of humans, we feel pleasure from keeping our body temperature at a consistent rate. Our body has a number of built-in mechanisms to dissipate heat or to retain heat. On a hot sunny day when you are sweating, a cool shade and a cold drink are desirable. On a cold wintry day when you are shivering, a warm bath and a cup of hot coffee feel divine. There is an urgency to seek thermal comfort because the body will die within minutes in extreme environments. It is just as important as breathing oxygen. Hot temperatures are more dangerous for the human body. That is why you collapse when it is too hot. While cold temperatures kill you slowly, it is possible to come up with cultural and technological strategies to combat against the cold. Seeking comfort from hot ambient temperature is more urgent than the cold. How can we discern different levels of temperature without being confused from sensory bombardment? Just as much as there are specific touch nerves to detect mechanical properties of an object or to connect with another person, there are also special nerves to detect heat and cold. They are distributed asymmetrically throughout the body. The face, the inside of the mouth, the fingertips, and other vulnerable parts of the skin have larger distribution of these nerves. A little change in temperature in these parts produce an instant behavioural reaction. It is the change in temperature that excites the neurons and produces pleasure or pain, not the temperature itself. When it is not changing, the body is used to the temperature and it becomes the new baseline. This does not guarantee that you will be comfortable with the said temperature. However, they become active once again when the new change deviates from the baseline.

Thermal comfort is a subjective experience that requires context. Imagine you work in a steel production factory with hot furnaces. When you enter it, you will feel the overwhelming hotness from the furnace. This effect is more pronounced when it is winter outside. In that case, the experience is slightly different. If the weather is very cold outside, you might feel a wave of pleasure when you enter the hot factory because the pain of coldness is alleviated by entering a warmer environment. Afterwards, the annoyance of extreme hotness will slowly bother you. After an hour or two, you get used to the ambient heat and barely notice it depending on job experience. You might still be uncomfortable by the hotness but you no longer react to it strongly compare to when you enter the factory. If you are new to working near furnaces, you will be more annoyed than a veteran who have worked there for decades. In another case regarding tactile thermal experience, if you accidentally touch an object which is too hot or too cold, the nerves bypass the spinal cord highway that will bring the signals to the brain and uses the reflex mechanism to move away from the dangerous object. As a result, the reaction time is faster to avoid any tissue damage. This does not require conscious input since higher level processing takes time while the skin suffers from the damage. Pain will follow half a minute later to discourage you from putting your hand into the hot place again.

If an object is within acceptable boundaries of temperature, the nerve signals are delivered to the hypothalamus which controls automatic metabolic functions and hormonal systems. Hypothalamus has the power to influence the mood and pleasure of a person due to many factors including temperature change, sleep, hunger, metabolism, sexual mood. Maybe winter blue is not just a metaphor after all. Seasonal affective disorder is a common mental illness that strike mostly women and some men around the winter times. The cold temperature and the cloudy weather suck all passion and energy out of the person. Depression soon follows and productivity levels drop. Due to low light conditions, the winter can mess up the circadian rhythms that will in turn disrupt sleep cycles. Hypothalamus is the source of seasonal affective disorder. But the brain is more complex than that because its structures are organized along a hierarchy. Also seeking comfort from your lover is tied to the thermal regulation system. Whenever you feel sad and depressed, your desire to seek out warmth and hugs increases. A tight long hug and warmth from your lover has the power to heal all mental wounds. Even a good love making can temporarily heal your mood for a time. Treasure these hugs and kisses! That’s why no one can survive alone. Being interdependent with someone you love is the best way to thermoregulate whenever you need it. This is not being clingy, it’s being smart according to how humans are evolved to survive.

It is so fascinating when we look at linguistics evidence of temperature metaphors, all languages from all cultures have them. There is a noticeable pattern in how we understand our emotions and describe our behaviours using these metaphors. If someone is attractive, the person is universally described as hot. The sexual attraction also activates the hypothalamus which in turn activate hot feelings in specific locations of the body. If someone is indifferent, cruel or unempathetic, we describe him as a cold person. This is also because empathy and compassion also activate hot emotions in the body which allow you to feel closer to another human being. If you lack compassion, there is no hot emotion and hence you are a cold person. These descriptions feel superficial but there is something deeper going on. The metaphors do not perform one way. Holding a warm coffee cup can trick your brain to think the person in front of you is warm and kind too. The metaphors represent temperature sensations while the tactile sensations can recall the metaphor. It is a two-way street. The hypothalamus is performing multiple functions and recycling the architecture of temperature detection for attraction and empathy via hormonal activation. If you lose all the top parts of the brain and the hypothalamus and lower parts are still intact, you might still be alive and can perform various biological functions. Of course, you will resemble more like an instinctive animal than a human being. There are no cognitive thoughts in your mind but you will still be alive. Higher level cognition is associated with the top cortex of the brain. While the hypothalamus is the minimum consciousness required to be alive even though it is such a small part of the brain. It is the relay station between the brain stem which regulates basic biological functions such as breathing, heat beat, temperature regulation, metabolism etc and the limbic system where emotion and motivation resides. The neural projections from the limbic system go through the hypothalamus which then order the brain stem to make changes in the body. Such as when you feel an attraction towards a person (an emotional state), your heart beats faster and your body feels hot (physiological change). Then the cortex interprets the person as being hot (metaphor). The other way around is also possible. If you eat hot spicy food, the brain stem will detect the increasing temperature and report it to the hypothalamus. It then will send projections to the limbic system producing positive or negative emotions. These emotions are then associated with whoever you are eating with. Yes, eating hot spicy food together with your date could increase attraction.

At the same time, we have to be careful when talking about language and temperature metaphors. Some images are unique to the culture and the climate in which the said culture operates in. For example, Indo-European languages tend to describe kind and compassionate people as warm while cruel and indifferent people as cold. Since Europe is located in colder temperate regions, warm temperatures are seen as more positive. This divide may not be the same in other cultures. In Burmese language for example, a cold person is referred to someone who is more peaceful, introverted, and easy going, while hot refers to someone who is stubborn and causes trouble for others. This is due to the tropical region where Myanmar is situated. Hot temperatures are typically seen as negative while cooler temperatures are more comfortable. On a side note, it’s funny how Burmese people make fun of western sunbathing culture. They don’t understand the appeal. Why would you burn yourself in the sun? How strange!

Ok then, how do different languages describe the temperature itself? There are three universal categories: ambient temperature, tactile temperature and personal temperature. Ambient temperatures are described using nouns because it is the general state of the environment. While we have no control over the weather, we have some control over indoor ambient temperatures due to central heating and air conditioning. Before central heating was invented, people tend to sleep together in the same room. Everyone in the family lie together closely near the fire especially in the winter. Just like penguin huddling, the body saves a lot of energy when being close to another. You can be clingy to each other and no one will judge you. After central heating becomes the norm, people can afford to live separately in individual rooms. I have made an interesting observation that the rise of individualism coincides with the wide adoption of central heating technology. The wider family unit is less important when there is a reduced need to huddle close to get the physical warmth. However, the tactile temperature is described using adjectives because the cortex is accessing the characteristic of a specific object when it is touching the skin. From a lifetime of experience, we know that metal feels colder than other textures like wood. It also feels more pleasurable to touch the warm skin of a loved one than a cold skin of a stranger. Lastly the personal temperature is described using verbs. This makes sense because verbs imply action and the motivation to change. When you are feeling comfortable with the temperature, it is often unspoken. It is when you feel either really hot or really cold, you want to do something about it quickly to regain the comfort. For example, most women tend to have problems with thermal comfort in the workplace. It is often too cold for them because the thermostat is set too low for their body size, skin fat distribution and height. So they have to wear multiple layers of sweaters to feel comfortable while the men and taller women don’t have to. A good solution to this issue would be to install thermal regulating chairs that can heat up according to the user’s configuration. Another suite of thermoception inventions is happening in the fashion industry where clothes contain special materials that can heat up which you can set up through a smartphone app. Once these are widely available, there will be less fight over the thermostat.

What about the temperature nerves themselves? How do they work? Here is a fun experiment for you to try at home. Bring three bowls of water. On the left is cold water, middle is at room temperature and the right is hot water. Put your left hand in the cold water and the right hand in the hot. Wait two minutes. Then put both of your hands in the middle bowl of warm water. What you will discover is a weird feeling that the left hand is feeling warm while the right hand feels cool. This is the evidence that our body cannot perceive the absolute temperature of the water, only how it affects the body. What is going on? On the skin, there are free nerve endings that detect temperature at various thresholds. They are also associated with pleasure when activated repeatedly. Sensitive areas on the skin including the sexual organs have a high density of these nerve endings. To be precise, the ion-channels on the outer membrane of the free nerve ending nerves sense temperature. These are called transient receptor potential (TRP) channels. They are protein gateways to allow certain cations (positively charged) into the cell in order to sense the environmental condition of the space outside the cell and to perform cellular regulation functions for homeostasis. Among the TRP channels, TRPV family is evolved to sense warm temperatures and one of TRPM family (TRPM8) is evolved to sense cold temperature. They produce electrical signals when certain thresholds of temperatures are detected in the environment. The thresholds are not sharp but blend into each other between the ion channels. Each TRPV channel detects a range of temperatures and there is overlap between them. However, it is not a precise thermometer like the mercury thermometer or the electrical thermometer that we are used to. TRPV4 detects cool temperatures, TRPV3 detects warm temperatures, TRPV1 detects hot temperatures and TRPV2 detects very hot temperatures. I don’t want to use precise degrees of Celsius to describe the ranges because there is a considerable variability between individuals. Interestingly, the chemicals in spicy food also activates TRPV3 which explains the burning feeling when eating it. Beyond TRPV2 is the activation of pain sensors. In the colder side of things, TRPM8 detects cold temperatures and if the temperature is dangerously low, pain activates. Therefore, pain exists at the extreme end of cold and hot temperatures. Beyond a certain point, we lose the ability to sense temperature and instead it is delegated to pain receptors because the body does not tolerate tissue damage.

In all my years, I have endured a variety of seasons the world has to offer. Summer, Winter, Spring, Autumn, Monsoon, Dry. Spring is my favourite season because the temperature is mild and the promise of summer is on its way even though I would curse at the hot temperatures during summer. Autumn comes second for the same reason as Spring for having mild temperatures with the added beauty of seeing colourful leaves on the ground. Swedish winter is the worst since it is bone chilling cold and the thick snow would block the train tracks. This was a nightmare since I remembered having to walk in the knee deep snow for hours to get to school. On the bright side, seeing the whole world in pure white and the falling snow are pleasing to the eyes. Moreover, going to a sauna in kalbadhus is a pleasurable past time for the Swedes during winter. The tropical summer in Myanmar is just as bad as the Scandinavian winter. Unlike European summers, the tropical summers are high in humidity which makes it difficult to breathe. The sweat does not evaporate properly and there is a risk of overheating which leads to weakness and dizziness. Saying that, the relief I feel when entering an air-conditioned building is beyond delightful. The contrast between the hellish hotness on the outside and the heavenly coolness on the inside produces maximum temperature pleasure. South East Asian monsoon season is the most unique in my opinion. For 3 months straight, it would rain every day. It is not like the light dribble of English rain. It is like taking a shower. 30 seconds in monsoon rain and you will be soaked wet from head to toe. When I was young, I loved taking a shower in the rain. I would run and dance around with the water. The refreshing feeling afterwards is incomparable. If the rain is severe, it becomes difficult to breathe and there is a risk of flooding in the area too. I also hated the dirty mud and smelly waters on the streets. There is nothing remarkable to talk about the dry season other than the fact that feeling thirsty is painful due to drought. Relieving that thirst with cool fresh water makes me smile for more than a minute. Most of my positive and negative emotions regarding the seasonality has been due to how my sensitivity to temperature interacts with the contrasting environmental cues. Visually I can appreciate all the beautiful aspects of each season because the visual sense is more emotionally detached than touch. This is why manipulating the seasons in video games is a lot of fun since they do not affect my temperature sense and I can fully appreciate them through the visual graphics. Some games like Forza Horizon 4 allow the player to freely switch the seasons on the fly.

Normally the seasons will be divided by a few months each due to the Earth’s yearly orbit around the sun and the oblique angle of its tilt. So, the human body is adapted to gradual change in temperature in between the seasons. The world never turns from hot summers to icy cold in one day unless it is a storm or some other natural disaster like the ashes from a volcanic eruption blocking the sun. Anyhow the transition period between the seasons makes you vulnerable to various diseases. My mom taught me to be wary of seasonal transitions and take extra precautions not to catch disease. If anything, a good sleep helps fight any disease. Right now, my mind is recalling a bizarre experience during my first trip to North America where I experienced all the seasons within a span of two weeks. To get the most out of our first trip we decided to first travel to Los Angeles then to New York, Niagara Falls and finally Toronto in gleeful ignorance. We departed from London around April which is springtime, my favourite season. It was slightly raining. Terrible British weather as usual. When we arrived to Los Angeles, it felt like fast forwarded a few months towards summer. The sun was beaming and it was hot. There are roads everywhere and not a green park in sight which exacerbates the urban island effect. We visited Santa Monica Pier the next day and I had a fun time there. Being at the beach really helps with adapting to the hotness. It reminds me of Grand Theft Auto. I found many gaming references there. A few days later, we took a flight to New York and jumped a few months again. Now it feels like Autumn is transitioning to Winter. It was rainy and cold. This is where my body starts to feel weird. I have never experienced such drastic changes in seasonal temperatures before. In my opinion, New York city is superior to LA. The Manhattan Island is walkable and there are a variety places to visit. I loved the museums and Central Park the most. I would never get lost due to the grid plan of the city. Seeing all the skyscrapers packed on one tiny island is a remarkable sight I won’t forget. It has only been a week and I am starting to miss my London home. But there are two more stops on the way. Next is Niagara Falls. When we got there, it was full blown winter. There was snow everywhere and half of the waterfall was frozen. I had high hopes to see it in full grandeur but was slightly disappointed. Although I was surprised to see how fast the water was moving near the tip of the fall. Those Daredevils of Niagara Falls have a lot of courage to sit in a barrel and ride the waterfall. Then we took a bus to the city of Toronto. On the way there, the snow cover of the land reminded me of the Swedish winter. Now I miss both my London home and old Swedish home. Toronto is similar to New York and Gothenburg put together. I enjoyed taking the trams around the city because that is what I used to do in Gothenburg. My most enjoyable thing to do in a new city is to explore alone on foot. Mapping out a new path in my mind is uniquely satisfying. Four days later, I arrived back home in London, I was relieved to be back to my warm comfortable room and soft bed. The trip was only two weeks but it felt like a whole year has passed in memory.

How does the thermoception pleasure model work? There are two dimensions to this: how fast of a change and how much of a change. Like a pendulum, the body is constantly detecting and adjusting the body with the environment. It is a representation of a negative feedback loop governing temperature regulation of the body. Thermoception Pleasure Model measures the qualitative emotions during a temperature change event and how that relates to pleasure itself. Quantitatively, everyone will have different ranges of temperature where they feel warm, bone-shaking cold or painfully hot. Nonetheless, pleasure is produced when the pendulum swings back and forth slowly, best at the point between ‘cheerful’ and ‘exotic’. Very quick changes of temperature will cause confusion and frustration on the body. Most people will get annoyed by sudden fluctuations between hot and cold especially if it is out of their control. But there is also a sense of fun and unpredictability associated with these quick changes. On the other hand, if the pendulum swings one way all the way towards ‘painful’, an emotional tension starts to build up due to how much a person can tolerate it. Then a quick drop towards a comfortable warm temperature will release that tension and produce a sensory pleasure. Thermoregulation of the body is being stretched (like a rubber) to the point of pain until released into a more secure position. This phenomenon is more related to nociception pleasure than thermoception.

While we are on the subject of warm temperatures, it is actually not as easy as it sounds to produce a perfect thermal comfort for everyone. Depending on the size of the body, layer of body fat, metabolic rate and even the climate in which the childhood upbringing took place, the comfortable temperature environment is unique to each person. There is also a daily cyclic variation in core body temperature which changes the thermal comfort. Basically, each of us has what I call a ‘temperature profile’ at any given moment. The temperature profile can change over time with age and the familiarity of new climates. Thus, a person will feel comfortable, safe and secure when the ambient temperature and humidity perfectly match the temperature preferences of the moment essentially allowing perceived thermal equilibrium to take place.

Back when I lived in Myanmar, one of my favorite weeks in the calendar was in April. This is the time of a very special event called Thingyan Festival a.k.a Water Festival. Over night, every street is being built with a concert stage mounted with high pressure water hoses of all sizes. The children are preparing water buckets and water guns to shoot at passersby on the street. I used to have a big water gun which I can use guilt free only at this time. It is a time where the women put down their hair, let loose and show off their assets because the clothes get drenched if you know what I mean. Same with the guys showing off their wealth and girlfriends. It is a time of celebration with music, dance and alcohol in the midday of summer. I have strong memories of this festival. My uncle owns a small truck with no roof which is perfect for touring around the city and visits the biggest concerts. There is a long queue of cars filled with people standing up in order to experience the biggest pressure water hose they can see. You know the one where the police shoot a firefighter water hose into a riot crowd to disperse them? In Thingyan Festival, we seek those bad boys for fun. Don’t get me wrong, it hurts a lot to be shot by such high pressure water. There is also the occasional ice water that some assholes have prepared to get an instant reaction out of the crowd. The traditional root of this festival is Buddhist in origin. Once every year, the royals, the monks and the common people partake in the water festival to cleanse their wrongdoings and be born anew for the new year ahead. It is a rather tame and dignified affair where they slowly shower each other with a golden cup of water. Not like crazy chaotic fun of the modern version.

Moral cleansing rituals are remarkably common across civilizations and religions. Before we talk about moral cleansing, you first need to understand the dynamic feedback loop between disgust and immoral behavior. The brain areas like insula associated with disgust are activated to protect you from unhygienic situations that can potentially cause disease. The disgust emotion also activates the gag reflex when you accidentally eat spoiled food. It works together with the enteric nervous system to expel the food if it is threatened with poison. This complex feedback loop is repurposed in the human species. Since humans were evolved in complex social environments, specific rules of the social game are learned during the upbringing. These moral rules are taught by the elders, enforced by law or implicitly negotiated between people across time. Without them the social game cannot function and we will all be reduced to animal instincts. It is absolutely fascinating when breaking the moral rules also activates the disgust emotion parts of the brain and the gag reflex. For example, you are a Muslim and your best friend who is also a Muslim falls in love with someone who belongs to a different religion and who loves the taste of pork. Or you are a Hindu but you like the taste of beef. Or you were manipulated when you are drunk. Or you indulge yourself with recreational drugs leading to addiction and loss of livelihood. Or you were jealous of a close friend who became successful all of a sudden. Personal failures, guilt, regrets and moral rule breaking build up tension in the emotional parts of the brain like amygdala, insula, hypothalamus etc. This happens not only for the one who break the moral law but also their neighbors who are observing them. Moral cleansing ritual is the solution to release such tension. Every religion has them. If you are a Christian, you are familiar with Baptism. If you are a Jew, you are familiar with immersion ritual of Tevilah. If you are a Muslim, you are familiar with daily cleansing rituals before prayer. If you are a Hindu, you are familiar with Kumbh Mela pilgrimage where millions of people visit the sacred Ganges River and bath in it. Ancient Egyptians had similar rituals involving the River Nile where the priests recreate the mythological drama of the Gods. Wherever there is a central river that guides the people of the land, you can bet that there is a cleansing ritual that is associated with the river. It is also likely that the people worshipped the river deities to protect them from flooding. Even the secular societies such as the Scandinavian countries have cleansing rituals like going to the spa and bath houses with family members. The ancient Roman civilization is famous for having a communal bathhouse in every town they have built. Bath, a town in Britain was named after the Roman bathhouse that is central to the formation of the town. I have visited it myself. The Romans used the bathhouses for both recreational and religious purposes. They were very meticulous with the actions of undressing, bathing, resting, massaging, courting, socializing, and making business deals. From a religious perspective, the cleansing ritual allows a person to be born anew like a spiritual rebirth where he is purified from the moral filth that he has accumulated throughout the year. Thermoception sense is the foundation for the feeling of rebirth to form in the mind. It gives the person a second chance to enter the social game where past crimes are forgotten and forgiven especially when the cleansing ritual is done in a group setting. The ritual creates a deeper bonding between the people who have shared their sufferings together.

These miracles are possible because of parasympathetic nervous system. Let me explain. The hypothalamus and the brain stem control the automatic nervous system which in turn controls the various function of the body and the inner organs. ANS reacts dynamically to the outside stimuli and the inner homeostasis of the body. There are two different modes of activation: sympathetic nervous system and parasympathetic nervous system. Parasympathetic nervous system responds to restorative environments and causes the freezing instinct under predatory threat. When the body relaxes, PNS enhances the efficiency of digestion along with slower respiration rate, slower heart rate, lowered blood pressure, constricts the pupils and increase the tear production. Parasympathetic activation is highly important in placebo medicinal and psychological prescriptions. Sympathetic nervous system on the other hand responds to high arousal or stressful stimuli and causes the fight and flight response when under threat. As soon as you feel vigilant, SNS inhibits the digestive system and redirect the energy to the muscles for immediate emergency response. It increases respiration rate and the breathing becomes short and fast. The heart rate is greatly increased along with the blood pressure to respond to the threat. It takes in more sensory information via dilating the pupils. Even the sweat glands are stimulated for high intense activity. Thermoception therapy can easily activate either one of the nervous responses. However the maximum pleasure is reached when a balance between parasympathetic and sympathetic reaches a stable equilibrium. This is when the highly engaging flow state is activated.

The parasympathetic nervous system activates during periods of relaxation. Like when you are watching TV, taking a nice long bath, listening to music while closing your eyes, sunbathing, reading a book while listening to the sounds of the sea. Taking the time off with loved ones or for yourself is very beneficial for the psyche. Having a ME time should be scheduled into the day and should be treated as important for the sake of avoiding a mental illness. The feeling of safety, comfort and coziness are essential for it to activate. This is why you can only relax when you feel at home and allow you to forget about the stresses of day. Unfortunately, our work obsessed culture has forgotten how to take a break. As a result, the 24 hour work day due to the constant connection of messaging and social media, the workers sympathetic nervous system is always active which make them feel a low level of stress and vigilance. The exhaustion levels can build up and up until a full-blown burnout is inevitable. The human body is not a machine. There is a limit to constant performance. The balance between sympathetic and parasympathetic activations are lost. There is a mistakenly belief that one should relax only during a vacation. Being at work means to feel the stress from constant performance evaluations. Things could be better. The benefits of parasympathetic activation during relaxation are too many to count. First of all, the immune system is activated only when you feel at ease. The white blood cells count jump in the bloodstream during the parasympathetic activation. This means that the body is prepared to defend against any kinds of illnesses. Secondly, being relaxed lead to a deeper sleep state at night which leads to feeling rested when you wake up in the morning. Having a good amount of sleep give you energy and motivation for throughout the day. Thirdly the parasympathetic activation allow the default mode network to emerge in the brain. When you are feeling relaxed and intentionally bored, the mind can wander to interesting and creative directions. This is why you get creative ideas when you are in the bath for example. New accidental discoveries and solutions are generated when you are not working. This is something the controlling managers can’t fathom. More work is being done by not working. When the active attention is allowed to rest, the subconscious parts of the brain can freely process the complex problems in the background. On the outside, you look like a lazy person doing nothing of productive value, but in the brain new neural connections are being made. The productivity levels after a good long relaxation can jump to a higher threshold compared to the steady grind of constant work with no breaks. Crunch work culture and overtime working hours are detrimental to the creativity of the workers. The intentional activation of parasympathetic nervous system should be a part of the management of the staff rota. The money saved by allowing relaxation is astronomical because the worker is less likely to be sick, more likely to be motivated, more likely to come up with creative ideas and more likely to stick with the company who cares about their well-being. It is far more costly to hire and train a new recruit than making the current skilled workers happy and loyal. The thermoception pleasure from relaxation is essential in achieving this outcome.

Even the video games understand the benefits of relaxation. A common game mechanic to measure the health levels of a character is called HP or Health Points. The health points determine how long you can last in a fight. When the health points reaches zero, a death screen pops up to communicate to the player that they have failed in an encounter and must restart from the nearest checkpoint. This is where the concept of healing comes up to restore the lost HP so you can keep going for longer in the game. Some special items or potions can restore the HP and they are common themes of every action game. In Genshin Impact, the players can cook a variety of cuisines from different regions. Every food has different bonuses like restoring health, stamina or buffing the attack value. Or in the Yakuza games, the player can go to a restaurant and eat food to regain the lost HP. But some games go an extra mile and design relaxation mechanics to restore the HP. In Death Stranding for example, the players are encouraged to seek out hot springs in the area in order to restore energy and HP from a long delivery journey. In Ghost of Tsushima, the hot spring mechanic increases the maximum vitality of the character. Meaning you become more healthy by going to a hot spring in different parts of the island. Moreover the character can reflect on what has transpired in the story to make better decisions in the next story arc. So the game is indirectly teaching the player that relaxing with thermoception pleasure and self-reflection leads to better outcomes in life. In the Dark Souls games, the player has to navigate a fantasy like world filled with dangerous traps and monsters. There are bonfire points hidden throughout the map. They are essentially a checkpoint for the player to relax and save their game. Since the souls games are famous for crushing difficulty and relentless enemy AI, the bonfire serves as a counter relief to constant aggression. Moreover the character is allowed to level up only at the bonfire points. If they explore too far into the unknown and ended up dying, they will lose all progress (souls) and revive at the nearest bonfire. After that, they are given one last chance to recover the lost progress by dashing straight to the location they died. If they die again on the way to it, then they lose all of it forever. In Final Fantasy 15, the main character travels on a road trip with three of his best friends. They will fight monsters and robots in order to solve the mysteries of the world. Things are relatively safe in daytime but when the night comes powerful demons can appear on the road itself to attack the group. So the player is encouraged to seek shelter at night by going to a camping spot or an expensive hotel. You can restore your HP and level up when you relax and spend time with your best buddies. Additionally, one of the best friends has the ability to cook tasty meals for the group. These foods give various in-game attribute bonuses just like in Genshin Impact. A good game cleverly design various stresses (that activates sympathetic nervous system) and relaxation (that activates parasympathetic nervous system) to motivate the player appropriately. A delicate balance is required. If there is too much stress, the player find the game too difficult to play and they will rush towards a relaxation spot. If there is too much relaxation and less penalty for failure, the game is perceived to be too easy. But if the balance is just right, an engaging flow state is achieved that motivate the player for hours and keep their mind immersed into the fictional world. Real life projects should follow a similar design philosophy to motivate the people for longer.

Going back to the cleansing ritual we discussed earlier, there is another kind of cleansing ritual that is just as effective as using water. When the moral filth has accumulated to a point where no amount of water can be used, a special ritual will be used to completely vaporize the outer frame in order to release the pure soul back to where it belongs. I am of course referring to the witch burning rituals. The witches were inheritors of ancient knowledge and fertility goddess rituals were still practiced in the countryside in much of Europe even though Christianity was the dominant religion in the Middle Ages. In addition, the knowledge is solely passed from the grandmothers to mothers to daughters. For hundreds of years, Christianity has tolerated their presence because they serve an important outlet for women to deal with puberty and childbirth. As Christianity becomes more fundamentalist and extreme, the male priests start to perceive these witches as a challenge to their absolute authority. Moreover, a woman’s body is perceived to be dirty and if a woman has consorted with a devil, their bodies are filthy beyond hope. So in order to completely destroy an entire religious system of the witches, the Christian authority rounded them up including, grandmothers, mothers and daughters and burned them all. In other words, it is a form of ethnic religious cleansing. By burning their dirty bodies, it is believed that their souls will become pure once again. Such an barbarous act were carried for at least 200 years until the ancient knowledge and crucial female rituals were lost.

Extreme heat has been used in rituals to cleanse ones body and soul, a counter ritual to using water to cleanse oneself. They pop up in various religion around the world like Shia Fire Walking, Bhutan Fire Festival, Christian Witch Burning or countless fire rituals in Hinduism and Buddhism. When I was young, there was a Shia mosque right in front of my house. Once a year during the Mourning of Muharram, the whole mosque becomes filled with people doing Shia rituals like self flagellation, fire walking and many others. Firewalking is the most curious ritual I have ever seen in my life. I mean don’t their feet get burned, it’s so dangerous. Technically its not really walking on fire but on coal embers. Plus they pour water on the feet before walking on it so the feet don’t get burned due to the water absorbing the heat first before reaching the feet. After participating in these rituals, both the adults and the young become very absorbed in their sensory stimulation which generates brotherhood and religious fervor. If you are atheist it would be hard to imagine such a scene but it is a wonderous sight what human beings are capable of. Looking at these rituals from the thermoception pleasure model, it is clear that creating the stress of extreme heat and releasing back into normal temperature builds up the tension and pleasurable release. This release can be used for creating group cohesion, religious feelings and becoming a part of something bigger than oneself.

Before we depart, I would like to spend a little time on the spiritual significance of thermoception. In the beginning of this article, I have hypothesized that thermoception is probably the first sense that life has evolved in order to detect the difference between inner environment of the cell and outer immediate environment. Only then can these early life forms be aware that it is alive. The spiritual significance of this fact is profound. You have also seen from the list that some cultures believe thermoception pleasure help in cleansing their sins like fire festival or water festival. Consider also the case of heaven and hell. Humans who live in different continents have independently came up with this concept. According to the Savannah hypothesis, human bodies especially the brain have genetic and subconscious psychological preference for the savannah climate and vegetation. Young infants look longer at landscape photographs of the savannah than any other biomes. Many descriptions of heaven such as an abundance of beautiful plant life, water streams, moderate temperatures and plenty of light all point towards our universal preference for the Savannah climate. Even if the heaven is located in the sky, these climatic elements are still present. On the other hand, hell is universally depicted as either too hot or too cold. Hell is eternal burning in the underworld or in the case of Viking hell, a cold uninhabitable wasteland where the Frost giants live. From the perspective of the thermoception pleasure model, hell is located at the painful end of the cold and hot spectrums. The underlying commonality between heaven and hell is thermal comfort. Humans have subconsciously decided across the world that heaven, if it exist has perfect thermal comfort suited to the human body while hell possesses inhospitable temperatures for the human body. This is how fundamental thermoception is to the human condition.

Thermoception Pleasure Model

Further Reading

© PEL COnsulting

Info

Action