Experiencing the world
1.1 FIVE SENSORY PORTS
Organisms are exposed to external environmental conditions like heat, pressure, chemicals, sound, light and so on, along with internal environmental components in the form of biomolecules, fluids, and forces. In between two vastly different environmental contexts, organisms survive by maintaining good ‘terms and conditions’ with both. To receive and process external data, nature has endowed humans with a set of five sensory organs (eyes, ears, nose, tongue, and skin) that collect, convert and relay signals to the brain for further processing and response.
Organisms also exchange another form of data among themselves that does not come from outside but is generated within. These are thoughts and emotions that form a subtle layer of construction, beyond the physical structure.
Given that our experience of the world is a direct function of the five sensory ports that capture a specific specimen of data - partial reality is our default setting. Its resolution is set by a combination of physical laws and unique organism specific biological mechanisms.
When we see an object, we only capture its ‘front view’. We do not get a complete 360-degree perspective in one visual experience. The scope and depth of this ‘gallery view’ is determined by the optic resolution, which itself is dependent on the construction of eye itself. The same goes for the data capture and compilation process determined by the other four input sensory devices.
Specialized cells within these sensory devices compile the raw physical data into a neural format for onward transmission, processing, and response.
The compilation of incoming physical data to an internalized version of neural format indicates that if sensory organs work at their peak efficiency, they can capture more data and if something goes wrong, the reality is experienced at low resolution. In other words, human experience is a function of data capture and transmission.
In general, living organisms capture three types of data
(i) light waves reflected from an external physical surface and hitting the retina to generate a profile of an external object
(ii) Chemicals floating in the air colliding with the nose and tongue
(iii) sound and other forms of electromagnetic waves striking the body and generating a response.
Let us quickly walk-through sense organs to get a broad perspective of how information are managed.
(i) EYES | SENSE OF SIGHT: Humans are endowed with a visual system made of intricately designed components locked into a series of three dimensional structures to generate an estimated 576-megapixel vision. In the animal world, eyes come with unique image capture mechanisms and resolutions.
An eagle soaring high in the sky can detect a rabbit more than 5 km away! Likewise, hawks, cats, and owls have far more powerful eyesight than humans. Key components employed to generate visual perception appear in the form of (i) cornea, lens, and retina supported by (ii) muscles, nerves, blood vessels, and (iii) space filled up with a gel-like substance that provides the much-needed lubrication and refraction.
The optical power of the eye lens is a collaborative effort of several components and does not remain constant throughout life. The optical power is determined by the lens surface curvatures, refractive index changes at aqueous / vitreous interfaces, and (an age-correlated) refractive index gradient distribution within the lens itself.
The retinal image is a collective contribution of cornea (providing 80% of the refracting power, refractive index 1.376), aqueous humor (refractive index 1.336), followed by a transparent crystalline lens providing 20% of the refracting power, followed by a large chamber of gelatinous vitreous humor with a refractive index of 1.337. The retina is the innermost, light-sensitive tissue of the eye that generates an inverted image from incoming light rays and sends the information to the brain for further analysis and interpretation. The retina contains millions of light-sensitive cells (rods and cones) that get activated when light rays hit the membrane.
In human eyes, there are more rods than cones. If there were more cones than rods our ability to detect color differences would have been very low.
Even though eyes in humans and eagles are near the same size/weight, eagles can detect a tiny object several kilometers away as their vision is 4-5 times better than human eyes.
Depending upon how much light passes through the pupil and strikes the lens, an image is created on the retinal screen (loaded with photoreceptor cells). With age, numerical and qualitative issues emerge with pupil, lens, gel-like substances, and retina affecting the quality of visual perception. Thus, the perception of reality that was already incomplete, gets further reduced.
(ii) EARS | SENSE OF HEARING: In humans, an ear is a sensory organ that enables hearing and balance. The human ear is composed of three parts: external, middle, and internal. The external ear is what’s visible from the outside as a cartilaginous structure. It narrows down into a funnel ending up in a tympanic membrane or the eardrum. The tympanic membrane sits at the edge of the outer ear and middle ear. Next in the sequence is the middle ear cavity which resembles a rectangular room hosting three small bones and specialized cells.
The inner ear is the main sensory organ and part of the central nervous system. It is responsible for transducing mechanical sound waves into electrical impulses for onward shipment to the brain. The Inner ear is also responsible for balance and orientation.
Pressure waves enter the outer ear leading to the vibration of the tympanic membrane. This triggers a series of events in the middle and internal ear resulting in the transfer of signals to the brain through the auditory nerve that interprets the incoming signals as sound. Ears are like reception counters for sound waves to be received, compiled, and transmitted through an internal “message-passing interface”.
Sound is measured in terms of decibels and frequency. Decibel refers to the loudness of the sound or the level of pressure it creates. The frequency denotes the vibration of the sound wave per second i.e., the number of times a wave repeats itself per unit of time. For example, a 100 Hertz (Hz) sound wave means that a wave is undergoing 100 repetitions per second
The normal human hearing range is 20 Hz - 20,000 Hz, with the sensitivity gradually declining with the age. Anything above 20,000 Hz is ultrasound and anything below 20 Hz is subsonic. Ultrasound waves come with a frequency of more than 20 kHz and cannot be ‘heard’ by human beings. Ultrasounds are used in echocardiography to construct images of the fetus during pregnancy, detection of cracks in buildings, measure the depth of the sea, and so on.
The comfortable loudness range exists between 0-100 dB beyond which it can get irritating. At 140 dB and above, the sound may damage the auditory system. Every day we experience a range of sound decibels e.g., normal breathing is 10 dB, a soft whisper is 30 dB, normal conversation is 30-70 dB, motorcycle sound and hair dryers are in the range of 95-100 dB, rock concerts are about 110 dB and jet engine sound is 140 dB.
Animals can capture a range of sound wave frequencies e.g., a chicken has a hearing range of 125 Hz - 2 kHz, an Elephant has a hearing range of 17 Hz-10.5 Hz, An Owl’s hearing range is 200 Hz - 12 kHz, a Dog’s hearing range is 64 Hz - 44 kHz range while Beluga Whale demonstrates a subsonic range capability (1 kHz - 123 kHz).
Animals hear sounds that are not registered by the human auditory system. Cats, dogs, and bats have an extremely sensitive hearing mechanism that surpasses humans in terms of sophistication. The ability of bats to catch flying insects in the air at full speed at pitch darkness is due to their advanced echolocation mechanism.
Given the human ability to capture sound data within 20 Hz - 20,000 Hz range, the “humanized” version of the sound wave spectrum is only a fraction of the sound waves and sensing possibilities that exist out there. Our perception of sound wave extract is yet another example of partial reality.
(iii) SKIN | SENSE OF TOUCH: The skin is the largest organ of the body that provides a firm cover and texture to the underlying bone, muscles, nerves, blood vessels, and so on. In absence of an opaque skin, we would have looked like a network of mechanical devices.
The semi-permeable skin of a human adult covers an area close to 20 square feet and delivers key functions of protection (from microbes), regulation (of body temperature), and sensation (touch, heat, and cold).
Three distinct layers of tissue make up the human skin. The top layer, Epidermis, provides a waterproof barrier creating a certain skin tone and texture. The middle layer dermis, beneath the epidermis, makes up to 90% of the skin’s thickness. It is rich in collagen, and elastin, providing a template for hair growth, sweat, and oil secretion. The deeper subcutaneous tissue (hypodermis) is the fatty layer that connects skin to muscles and bones.
Data indicate that one inch of skin comprises approximately 19 million skin cells, 60,000 pigment cells, 1000 nerve endings, and 20 blood vessels. On average 40,000 old skin cells are shed every day leading to the growth of new skin every month.
An evolutionary comparison of the skin shows that animals have the best sense of touch in the world. A catfish does not have scales and is endowed with tiny hairs that act as super sensors. A duck-billed platypus locates its prey by monitoring the electrical pulses in water. Snakes detect infrared (thermal) radiation emitted from the bodies of animals they prey upon.
The Jewel beetle uses a rich bed of sensory cells on legs that can detect even fire, several kilometers away. Likewise, the abdominal skin of cricket helps them determine small changes in the airflows and navigate accordingly. Even a tiny single-cell organism like paramecium has a rich cover of cilia that help them move towards the food source and away from danger.
In the human womb, the fetus can sense its surrounding through the skin as early as eight weeks. The data shows that our experience of the sense of touch is highly diminished in the animal kingdom. Added to this natural restriction, is our obsession with skin care products that further decreases sensitivity.
(iv) NOSE | SENSE OF SMELL: The sense of smell is called Olfaction. The process of smell perception starts with specialized nerve receptors located within the nasal cavity. When we inhale or sniff, some airborne chemicals bind to the receptors triggering signals that travel through the olfactory nerve, to the olfactory bulbs. The human olfactory experience presents itself with a huge variation. Reports suggest a combinatorial involvement of 400 olfactory genes with distinct genetic variability. Interestingly, some of the recent work suggests that human olfactory sense may be slowly fading.
The nose is a terminal part of the respiratory system that facilitates the passage of air into the body, filtering the debris (including allergens), generating a sense of smell, and warming and moistening the air before it enters the lungs.
The nose is made of bone and cartilage to form nasal cavities and soft muscular skin to form the wall of the nose, sinuses to keep the nose moist, hair and cilia to trap dirt and particles, and nerve cells to register a certain smell data (in the brain).
For many years, scientists believed that humans were not very efficient in detecting odors (in comparison to animals). This was because more than 1000 different kinds of smell receptors were found in mice and rats, compared to humans with around 400 receptors. However, some recent studies indicate that humans can detect at least 1 trillion different odors.
Interestingly, the human language does not have words for a trillion smells!
Though humans come with a wide range of odor sensitivities, animals have a wide range of sensitive odor-sensing capabilities that far exceed the human olfactory sense.
Interestingly, Sharks dedicate a significant portion of their brain to smell detection. It has been reported that bears can detect the smell of a dead animal tens of kilometers away. Polar bears can detect a seal through 3 feet of ice using their strong sense of smell. Elephants can perceive water from a very long distance even when the water body is completely detached from the view. Snakes have a highly developed sense of smell and use their tongues both for taste and smell.
Data indicate that dogs’ sense of smell is at least 10,000 times more sensitive than humans and may detect human odor days after the person has walked that area. Dogs are trained to sniff out explosives, drugs, and even disease conditions. In dogs, the olfactory bulb is highly developed and approximately third times the size found in humans.
Unlike other senses, the olfactory nerve does not send the data directly to the thalamus part of the brain. Instead, the data feeds are routed to brain areas for creating emotions and memories. No wonder smells generate emotions in addition to memory. Just like fingerprints, every person has a unique odor/scent. The sense of smell varies from person to person, based on their genetic differences, dietary habits, and sophistication of the sensory apparatus.
(v) TONGUE | SENSE OF TASTE: The tongue is a thick and moist muscular organ fastened to bones of the oral cavity by ligaments. Its principal functions are mastication, swallowing, and speech. The tongue is enriched with tiny projectiles (papillae) that pack thousands of taste buds for detecting flavor. Each taste bud has 50-100 taste receptor cells that specifically respond to a certain input. The taste buds are connected to the nerves that pass signals to the brain and generate a sense of taste.
Traditionally, four distinct regions of the tongue (particularly tip and edges) have been known to be involved in generating tastes like sweet, salty, sour, and bitter. Recently, it was found that there is a fifth basic taste - Umami (as in Monosodium Glutamate, MSG). Also, it was reported that regions are not distinct/isolated. There is an overlap, and some regions are more sensitive than others. Essentially, unique receptor proteins are differentially activated based on the type of chemicals that come in contact.
In the animal world, it has been found that they have an incredibly superior sense of taste to humans. For example, Fish may be 25 times more sensitive than humans in perceiving taste and can detect a drop of blood kilometers away. A catfish can have more than 100,00 taste buds compared to 10,000 of a human tongue. Interestingly, birds have very few taste buds. For example, chickens are reported to have only about 30 taste buds while cows seem to have over 25,000 taste buds. Many taste buds in herbivores like cows helps them in identifying if a particular plant is toxic.
A quick numerical count of taste buds may be an indication of the resource allocation. However, animals with the highest number of taste buds does not indicate that they can taste the largest variety of chemicals. It is the diversity and density of taste receptors that determines the heterogeneity of taste experiences. The evolution of taste buds has supported optimal survival of an organism in a certain environmental niche.
In general, animals see, smell, and taste the external world differently than we do. Sensory organs create a unique internal example of the physical and chemical world outside the body.
Interestingly, our senses are always outbound, not inbound. For example, we do not hear our own heartbeats. We do not hear strong muscle contractions of the stomach or the sound of the blood flow through veins and arteries. Even abdominal sounds are heard only when they get louder for the ear to pick up. Nature has designed humans to hear external sounds but not internal sounds. To perceive what’s within, a set of five senses are not useful.
The degree of our experience depends upon the design and performance of five sensory ports i.e., their ability to catch the input, convert physical data into neural format, and deposit biological data into the brain for further storage of, analysis, and response. As shown above, animals are far more advanced than humans in all five sensory departments i.e., the data they perceive is far more detailed than the data interpreted by humans. It is not only animals vs. humans but also a huge variation found among humans i.e., no two human experiences are identical in perceiving reality. Turns out that the ‘mighty’ human sensory experience is just a tiny extract, a tip of the iceberg!
Human interactions form the core of any society. Interactions mostly show up as audio-visual and emotional data. Though emotions and thoughts are distinct entities, they almost always appear together.
When a person laughs, it’s precursor is a thought. However, during laughter, there is no thought … it’s only a thought-free (emotional) intensity. Thus, thoughts and emotions are different entities that show up together as a team and are influenced by five sensory ports. Nevertheless, human beings experience two more levels: virtual reality & absolute reality.
1.2 VIRTUAL REALITY
Sleep is a subconscious state of mind that is characterized by shutting down the voluntary responses. It is a reversible physiological state that is frequently characterized by dreams.
Though one may think of sleep as a resting phase for the human body, interestingly the brain and spinal cord work at their peak efficiency when the external inputs go down to zero!
Dreams are neural movies that are played on a virtual canvas of mind waves. The sleep state is a virtual manufacturing platform beyond time and space. It is an interesting passage into the infinite universe of consciousness.
During dreams, one becomes the creator of an emotional audio-visual movie with distinct composition, context, and response. Dreams are the most sophisticated virtual reality experience that humans create in almost every sleeping cycle. Interestingly, in dreams, the concept of space and time gets dissolved.
By closing the eyes, the finite leads to an infinite experience.
Dreams are personalized videos of the mind that create a remarkable and profound sense of ‘reality’ during sleep i.e., the writer, director, and producer is US. Upon closing the eyes and nodding off, one generates an emotional movie on the canvas of the mind with a great sense of vividity and vivacity. In dreams — spaces, species, and sentiments are intertwined, exist in parallel, and often beyond logic.
Dreams are transitory virtual experiences and are mostly forgotten on waking up. Data indicate that people dream more than once per night with blind people dreaming more than sighted people. There are no clear explanations of this interesting observation. During a dream state, if immense fear and distress are created leading to pain or choking, it’s called nightmare.
Several questions arise when one moves from the conscious to the subconscious world.
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Are dreams standard creations of the human mind or do they have some purpose/application?
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During dreams, is one just recycling the old data, generating new data or engaged in both the activities?
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How many people view dreams in color or black/white?
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How do real-life experiences impact the content of dreams?
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Do animals also dream? If yes, do they show the same REM-like stages found in humans?
Dream researchers are grappling with the fundamental question of how a ‘real’ experience is created by the brain out of seemingly no physical substance. While nobody has a clear idea of how electrochemical data and computational power of the brain generate emotional movies on sleep, data indicate that the hippocampus, a structure deep inside the brain, plays a key role in this process. A significant reduction of sensory inputs (on closing the eyes) enables the brain to create objects, actions, and perceptions into a rich experience.
Moving from the virtual world to the real world, one looks for molecular signatures of human experiences, to describe and control the process for future applications. Scientists move from gross anatomy to molecular biology in search of answers.
One of the time-tested methods that has helped scientists to study genes and proteins. Essentially, the trick is to either drastically lower gene expression (downregulation), tamper the sequence to make it non-functional (genome editing) or remove them altogether (knockout) to determine their function.
Using this approach, researchers have tried to find molecular or tissue level correlates of the dream states. Interestingly, people with damaged or missing hippocampus have reported difficulty in imagining spatially coherent scenes and stories in dreams. Directions like the front, behind, right, and left are largely omitted from their dream descriptions.
The discovery of rapid eye movement (REM) has led to the identification of several distinct states in sleep.
Stage 1: Eyes closed, easy to wake up. Thoughts are getting reduced. Breathing is regular.
Stage 2: Light sleep. Body temperature drops, and heart slows down. The body prepares itself for deep sleep.
Stage 3: Deep sleep. Body temperature and heart rate are at their lowest. Characterized by slow delta waves, the body repairs itself, boosting immunity. Dreams appear.
Stage 4: REM Sleep. Brain activity is intense, resembling the fully awake state. Loss of muscle tone, irregular breathing, and increase in heart rate.
Dreams appear. Rapid Eye Movement (REM) sleep is known by several names like active sleep, rhombencephalic sleep, and dream sleep. Neurons in the brainstem (junction of brain and spinal cord) produce chemical transmitters called norepinephrine and serotonin, to keep a person awake.
Neurons located at the base of the brain are responsible for moving a person into a sleep state by turning off the incoming signals.
Dreams have been found to be associated with a parieto-occipital ‘hot zone’ where there is a decrease in low-frequency EEG activity. The high-density Electroencephalography allows a clear distinction between the REM and NREM states during dreams. By monitoring the posterior cortical regions of the brain (real-time), it’s possible to predict whether a person may be going through a dream state. Studies show that up to 70% of Non-REM sleep may consist of dream experiences.
Given that dreams are ‘real’ in our experience and affect our perception, a formal study of dreams may be introduced in sociological sciences leading to a research project on developing Dream dictionary (based on evidence, logic and reasoning).
Moving further, several questions are waiting to be answered in dream science e.g., can one move into the dream state (consciously), without losing wakefulness i.e., if one takes control of all the five senses and shuts down transmission of incoming signals, would it be possible to create dreams with eyelids open? How far does the boundary of sleep extend, beyond which an uncharacterized territory of life energy shows up? The science of sleep is structured over a fascinating space that is bound to generate novel and mesmerizing discoveries of our life operating system.
Additional Reading
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Poe GR et al. Experience-dependent phase-reversal of hippocampal neuron firing during REM sleep. Brain Re. 2000: 855, 176-80
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Siclari F et al. The Neural correlates of dreaming. Nat Neurosce 2017: 20 872-8
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Wamsley EJ. How the brain constructs dreams. Elife 2020: 9: e58874
1.3 ABSOLUTE REALITY
A reductionist view of the human body takes a person from the phenotypic description down to the periodic table of elements. Data indicates that 28 elements may have been used to construct the human body. Interestingly, all these elements come with 99.9% space. The tiny atomic ‘bubbles’ pile up in large numbers to build molecules, cells, tissues, and organisms. Interestingly, the atomic ‘boundary’ that we see in textbook diagrams is a ‘construct of convenience’, as there is NO border in the real sense.
The question is: What is the space itself made of? Is there something beyond space and time or is it the final frontier of human pursuit?
The space that we know, is the cosmic ‘connective tissue’ that hosts air, dust particles, and waves (soundwaves, radio waves, light waves, microwaves, gravitational waves, etc). To get a real sense of space, one needs to subtract physical components and understand space as existence or nothingness (no-thing).
It is intriguing how nothingness, the core of existence, leads to somethingness.
The theory of relativity is built upon the famous e=mc2 equation developed by Einstein. The equation indicates that if something moves fast enough, it becomes nothing (energy).
Few questions emerge from this equation:
1. Can one 'slow down' nothingness to synthesize ‘something’? 2. Does the equation suggest that nothingness (energy) is moving at the speed of light or perhaps faster?
Furthermore, on moving from ‘relative to absolute existence’, one wonders ...
1. What is nothingness made of?
2. Where does ‘life energy’ come from?
3. What is the composition of life energy?
4. What happens to the life energy at the death of the Universe and the birth of the next one?
Moving towards “absolute existence” generates more questions, requires new tools of investigation and is an unchartered space. Assuming that life on this planet is a derivative of solar energy, it would be useful to know:
How is soular energy different from the solar energy? Does the Universe run on a fixed soul budget or do brand-new souls get cooked into physical existence every moment?
Currently, we have a baby-step understanding of consciousness. Science has to go beyond interesting neural correlates at the phenotypic level and understand “life operating system” with / without the body envelope. Developing analytical tools to visualize life energy and its dynamics, within and outside the body, is the need of the hour. Scientists need to build a periodic table of the Life Operating System!
An absolute experience untainted by sensory data, is beyond inputs received from sensory ports. The world of thoughts made of memory and imagination needs to be subtracted to reach an absolute experience. Using mind as a lab, reductionism as an approach, and intensity as the key, people have reported an experiential description of nothingness using tools of prayer and meditation. However, from a scientific perspective, the existence of the superconscious state / nothingness is still an interesting logical derivative.
To take absolute experience into the classroom setting and make students future ready, curriculum upgrades in sociology would be required that deal with the fundamental building blocks of the human body (beyond biomolecular description).
Physical Sciences have largely dealt with the layer of the gross body. Social Sciences and humanities have almost entirely been built on the chassis of thoughts and emotions. It’s time for ‘Life energy’ to find its presence in the training programs and research projects and make the learning complete.