From Dust to Descartes Page 2
In reality, we never experience anything except combinations of firing neurons from which we learn to infer facts about the external world.30 We never really ‘see’ the wind, just its effect. But as long as the response is consistent and distinct, as long as a given external condition always produces the same internal response, it doesn’t make any difference. Just as it makes little difference if a message is transmitted by Braille, Morse Code, sign language, or smoke signals as long as the same information is conveyed. Again, the important thing is that the mental impressions be consistent and distinct. What they are is less important. For example, in one experiment, a subject put on goggles whose inverting lenses caused him to see the world upside down. Although at first he was extremely disoriented and his vision confused, he eventually learned to deal with his new inverted world as adeptly as he dealt with his old one. In time, his visual field actually flipped over and the world appeared exactly as it did without the goggles.31 Thus, two different sets of internally consistent retinal images ultimately produced the ‘same’ mental impression.
Sensation begins with a reaction to the presence of something in the external world. Through chemical/physical reactions (a series of if event X then event Y relationships), physical energy (light, sound, etc.) is taken from the environment and translated into a consistent but internalized code32 of neuron firing patterns. Human sensation is much more, but at this stage we aren’t assuming any awareness only conditional reactions. The mechanics (although not the experience) of taste, smell, touch, hearing, and sight can each be explained by sophisticated and changing patterns of sensory input. There are no internal pictures, no internal smells or sounds, just reactions to the external world which act as representations of it.33
Detection And the External World
Our capacities of sensation are limited by what our neurons can detect. Photoreceptors in our eyes are triggered by light with wavelengths of 650 and 450 nanometers (red and blue), but not by infrared or ultraviolet light, which have wavelengths of 750 and 350 nm. We are equally blind to X-ray, radio wave, or microwave “light”. Red, microwave, orange, radio waves, and blue “light” differ from each other only in wavelength and energy. Yet we see some and not others.
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Of the myriad of things going on in the soup of interaction we call the universe, our bodies are capable of picking out only certain interactions and these at only certain levels of precision, particularly those which have had some survival advantage in our evolutionary history. We have photoreceptors to detect certain differences in the wavelength, energy, and concentration of light (vision), contact chemical receptors of water-soluble materials (taste), distance chemical receptors of vaporous substances (smell), mechano-receptors of vibrations in the air, liquids, or solids (hearing), and mechano-receptors of differences in pressure, temperature, and muscle tone (touch). We know that other animals have many of these same capabilities to greater or lesser degrees of sensitivity. Bees, for instance, can detect ultraviolet light, but don’t seem to be able to see red. Dogs can smell with a precision comparable to our ability to see, but are thought to be colorblind. The sonar capabilities of bats and dolphins allow them to use sound to ‘see’. The possibilities go far beyond our five senses. Some fish, birds, and insects, for example, use electro-receptors to detect electric fields when hunting prey or magnetic fields to aid in navigation. There may be any number of events occurring in the universe of which we have no way of knowing. When we do manage to extend our awareness beyond the boundaries of our innate sensation (infrared, sonar, and radar, for example), it is only by relating them to events within those boundaries. There are an infinite number of ways of sensing and dividing the world. How we do so is primarily a function of our biology.
Nothing up to this point is particularly controversial, but it is essential to understanding the rest of the paper. The only knowledge we have of the external world are our internal reactions to it. Sensations more accurately are changes in the organism rather than the external world. To borrow an expression, “It’s all in our heads.”35
“There is more to seeing than meets the eye.” 36
Our ability to detect certain aspects of the external world, at particular intensities, can be a complicated process, and we still cannot explain all the details. The focus of this paper is not the intricate details of sensation, but how and why we are aware of its results in a way that cameras, bars of iron, amoebas, and insects are not. At this point in the development of consciousness, all we are going to ask of sensory apparatus is that it be able to consistently produce different signals indicating the presence or absence (on/off) of certain external conditions, nothing more.
For the purpose of our argument, let’s imagine a substance, the brain, which instead of having the chemical property of changing its external surface in the presence of oxygen (like iron) changed, through a different, but no less mechanical, chain of chemical reactions, its internal structure in the presence of light or electromagnetic radiation -- like water, which changes its internal structure as a function of heat; carbon which becomes coal or a diamond depending on the pressure; or a plant, which changes its internal processes as a function of light. Furthermore, let’s assume that in this particular substance,
-- Electromagnetic radiation between 400 and 700 nm and with differences in wavelength of between 1-6 nm; edges at various degrees to the horizontal; movement in various directions, various shapes (rectangles, stars, etc…), along with the position of objects in the visual field. (as in Sight)
-- Vibrations in air, liquids, or solids between 15,000 and 20,000 hertz; the start or end of these vibrations; the rate of change of their frequencies; whether those frequencies are rising or falling (as with Hearing)
-- Various airborne and water-soluble chemicals. (like with Smell and Taste)
-- Changes of pressure or temperature in the body’s outer layer as well as changes in various internal systems (energy levels, position of limbs, body movement, etc.) (as in Touch)
each produced distinct internal configurations. What have we got? Still not much more than a rock. A peculiar one, but a rock nonetheless. Throughout this text, I will use sensation, sense, see, etc. interchangeably with “detection” to suggest nothing more than a chemical reaction that takes place only in the presence or absence of particular substance or external condition. Yet, this cannot be the complete explanation of what it means to “see” color or “hear” a sound. We can build machines and tools such as cameras, recorders, mouse-pads, smoke alarms, and litmus paper that can “sense” in this very limited way, and, in some cases, much better than we can. Our instruments, for example, can detect and distinguish electromagnetic radiation all along the spectrum, not just the limited range of visible light. But we don’t think of them as “seeing”. (Also, the photoreceptors triggered by an optical illusion remain the same, but our perception of the image changes.) This mechanical, causal explanation of sensation in terms of stimuli detection is not enough to explain what it means to consciously ‘see’ blue, ‘taste’ a dessert, or ‘feel’ hunger. There must be something more going on when I see an awe-inspiring landscape than just the mere fact that I am looking at it.
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Venus’s Flytrap- Common in damp, mossy areas of a small region of the Carolinas.
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Reaction
Reflexes & The Evaluation of Sensation
Beauty is in the eye of the beholder.
One thing that is missing from the preceding explanation of sensation is meaning, which is something that we bring to the world, not something we find in it. “Our very sense perceptions are altogether permeated with [evaluations] (useful or harmful, hence acceptable or unacceptable) … Even [some] insects react differently to different colors, one preferring this, another that.” 39 Sensation means nothing outside of a context. We do not merely sense the world. We sense what it means to us.40 In fact, organisms never just detect things. They react to them showing different levels of attraction, avoidance, or indifference. Although, we have begun another chapter to talk about it, there is no real distinction between detecting and reacting. Iron reacts to oxygen as much as it “detects” it. A bacteria or plant does not simply detect light, but rather its presence is just the sine qua non or initial link for a chain of chemical reactions that eventually results in the creation of chemical energy. Likewise, the pressure of an insect or small animal on the hairs of Venus’s Flytrap triggers the closing of the surrounding leaves and the beginning of the digestion process. With insects and reptiles, the reactions to stimuli (detected phenomena) are more complicated (because there are many more interacting chemical reactions), but no more sublime: a certain sensation sets into motion a sequence of bio-chemical reactions that eventually trigger a certain reflex, like pulling your hand away from a hot iron.
“Every [organism] in order to develop, maintain, …and reproduce itself, must perform a number of …functions such as respiration, ingestion of food, construction of new tissue, excretion, defense against assault and disease, … copulation, and so forth.” 41 This requires that the individual have certain dispositions or tendencies toward certain sensations42 as well as towards stimuli that may aid or inhibit these functions. Take fear, for example. Although it is doubtful that animals instinctively fear specific things such as bears or eagles, they (and in many cases we also) are pre-wired to have fear responses to the detection of certain stimuli such as large size “(as in the case of large animals); large span (as in flying [predators]); type of motion (as in reptiles); certain sounds (such as growling)…A baby-chick does not know what eagles are, but promptly responds with alarm and by hiding its head when wide-winged objects fly overhead at a certain speed.”43 Sudden cha
nges in sensation automatically place the organism in an orientation/surprise mode with its various fight or flight responses.
Robert Plutchik identifies eight primary behavior patterns or orientations toward stimuli which are necessary for survival and under which we can classify the various innate reactions to sensation.44
Incorporation. The acceptance of certain external stimuli.
Rejection. Behaviors involve ridding the organism of something that has been incorporated (such as spitting out poisonous food) or with decreasing or eliminating stimulating conditions.
Destruction. The elimination of barriers to the satisfaction of other drives. In simple organisms, this may be fused with the incorporation drive as the organism breaks shells or other outer coverings to obtain the food within.
Protection. The retreat from certain stimuli.
Reproduction. These behavior patterns involve maintaining or increasing the stimulating conditions.
Deprivation. State associated with the loss of incorporated or pleasing45 stimuli.
Orientation. Behavior patterns triggered by contact with a new or unexpected46 sensation. It is usually transient and exists only until the stimulus has been evaluated in terms of one of the other seven behavior modes.
Exploration. State in which an organism explores its environment. The exploration may involve any of the various sensations (vision, smell, tactile sensation) and the actions associated with this state tend to be spontaneous and continuous. It can almost be thought of as the default state, what the animal does if there are no other, overriding reactions. Many animals move their heads or eyes from side to side while Paramecia just move back and forth. In more evolved animals, the exploration may be more active especially in childhood.
These modes may be exhibited at various levels of intensity. At the lower levels, they are not so much an organism’s exhibited pattern of behavior in response to a stimulus, as much as they are the readiness, drive, or disposition for such a behavior pattern.47 It’s an orientation towards rather than a necessarily overt reaction to a sensation. The best way to look at it is that these states are the body’s preparing itself to employ the reflexes appropriate (evolved) to the sensation or situation. It is a shifting of an organism’s energy towards examining, maintaining, increasing, or eliminating a sensation. For example, with a lower level protection response, the heart may begin beating faster in preparation for the possibility of flight.
Relating these prototypic behavior patterns to higher vertebrates, the destruction pattern is associated with anger; “the protection pattern with fear, the rejection pattern with disgust, the deprivation pattern with sorrow, the reproduction pattern with joy, and incorporation pattern with acceptance. The orientation pattern would be most closely related to [surprise] and the exploration pattern with something like [attentiveness or] curiosity…” 48 Human emotional reactions are not so simple as stimuli-reflex, but our most basic, instinctual reactions to stimuli are thought to have their origin in much simpler creatures. As a form of shorthand, this book will use the word “emotion” only to refer to the eight instinctual reflex patterns outlined above, because as we explain human emotion and its subjective experience, we will build upon these simple reactions. We will revisit the uniqueness of human emotion in Parts II and III.
Approach/Withdrawal. This conceptualization of the emotions is even more simple when it is thought of in terms of four bipolar approach-withdrawal mechanisms: fear being the opposite of anger, joy of sorrow, acceptance of rejection, and attentiveness/expectation of surprise.49
(Plutchik’s analysis postulates eight primary emotions. Other researchers, like neurologist Antonio Damasio, have suggested five: Happiness, Sadness, Anger, Fear, and Disgust.50 It is easy to imagine there being only four or even two (attraction and rejection). For our purposes, ascertaining the exact number of primary emotions is not necessary. As we will see later, any set of categories or classifications is constrained to some extent by language and culture. The main point here is simply that organisms are born with some finite number of instinctual reactions to the stimuli that they are able to detect. Nonetheless, for convenience, we will continue to use Plutchik’s categories and framework as we explore other issues.)
Survey of research on basic emotions.51
Nothin’ Personal, Just Business
Whether it be an initial reaction of desire, aversion, or indifference, “emotions” evaluate sensation by preparing the organism to react towards stimuli “in a way that has been most adaptive in the history of [its] species.”52 “[I]n the case of fear, [the reaction is] protection from the stimulus; in the case of anger, destruction of the stimulus; and in the case of [acceptance], encouragement or enticement of the stimulus”.53 So for every possible sensation there exists a set of instinctual emotional reactions unique to each species and individual. Yet, this ‘reptilian’ level of awareness is still no more than action-reaction, stimuli-reflex. When a snake attacks, it needn’t have any conception of attacking to eliminate a threat or even to eat. In fact, under this view, there is no conception of anything at all, just an evolved, preprogrammed attack response to, say, the sensation of being stepped on [rejection]. Whereas, in the sun, the cold-blooded creature’s instinctual incorporation/reproduction response would be to remain immobile in the absence of any overriding sensation. Responses to internal stimuli could be thought of in comparably mechanical terms: a lack of oxygen increases the rate of breathing. Nerve cells triggered by an empty stomach may cause the reptile to enter exploration mode. Once its infrared sensitive neurons detect the small, warm mass of a mouse, an attack [destruction] mode, is immediately followed by the incorporation responses (to the ‘feel’ of the prey) of eating. An increase in blood density accompanied with dryness sets the organism searching for liquid.54
The above discussion shows how various sensations produce unique changes in an organism’s general orientation (inclinations, priorities, energy, attention)55 towards its environment. Simply put, an organism has states or modes in which various reflexes cause it to act in a certain way. Even so, reflexes are not self-awareness and alone do not involve much consciousness. Organisms from bacteria and insects to fish, reptiles and, in a very rudimentary way, even simple robots can achieve as much: reacting to a given set of conditions in a certain, predetermined way. Conceptually, it’s the same thing as flipping a switch to turn on a light, putting a car in drive, reverse, or neutral, or setting the central heating system to maintain a certain temperature by going into heating mode if the temperature falls below a certain point and into cooling mode if it rises above another. Although recognizing a snake as something to be afraid of or savoring your favorite dish requires more than just detection and reaction, for now it is only necessary that our organism have eight basic modes of operation corresponding to eight different ways of reacting to or orienting itself towards possible sensations: Incorporation, Rejection, Destruction, Protection, Reproduction, Deprivation, Orientation, Exploration. Each of these modes of operation should have various levels of intensity or activation and be capable of coexisting (at least at the lower levels of intensity). These initial reflex reactions should be predetermined and instinctual according to the organism’s environment and the sensations it is likely to encounter. For instance, rejection reactions for sensations likely to damage the organism (e.g. poisons, the puncturing of the protective tissue, extremes of temperature, sound, intense light) and incorporation/reproduction responses to certain sounds, tastes, colors, and other sensations that are beneficial in some way (food, rest, caresses, etc.). Human newborns, for instance, have reflexes for sucking, grasping, looking, turning the head, orienting themselves in the direction of a sound, and instinctively prefer [incorporation; reproduction] human cuddling, voices, and faces to non-human stimuli.56