The Original Version – Chapter 6

Theorem V: Conscious Awareness and Conscious Experiences are the Special Signaling Patterns of the Consciousness Neural Process

6.1 Definition of consciousness

If we inspect our minds while we are not doing anything in particular, we will find that there are many mental processes going on simultaneously as resting-state mental processes such as thinking casually, experiencing light mood, perceiving non-significant sensations (inactive vision, soft sound, light touch, etc. from the idle surroundings), being aware of space and time, being aware of self and non-self, and being aware of these on-going conscious mental processes. When there is a strong enough stimulus, either external (a flash of light, a loud call, a sharp pain, etc.) or internal (a popping-up thought of an urgent task, a sudden reliving of an exciting incident, a pang of sorrow, etc.), there is a mental process or mental processes that register this stimulus, direct our attention to, and keep our concentration on that stimulus, and our mind will become less aware of the resting-state mental processes that are not related to the stimulus. For example, when we are watching an exciting movie, we may not be aware of the sounds in the surroundings, not register the pain in our back, and not feel the anger, sadness, or happiness that we had before. In some circumstances, some of these mental processes may even cease functioning for a while, such as when we are overwhelmed by strong emotion, we may be stunned and unable to think for a while, or when we are intensely concentrating on solving difficult problems, we may not experience any mood for that period of time. But, whether we are doing nothing in particular or concentrating on something, there is one mental process that is always working when we are conscious. This mental process functions to be aware of other mental processes and itself with the awareness of their occurrences and of what their phenomenal characteristics are like occurring. Simultaneously, it also functions to experience the phenomenal characteristics that occur from other mental processes and itself. Thus, according to the definition of conscious awareness and conscious experience in section 3.2., this mental process functions to create conscious awareness and conscious experiences. In this theory, this mental process will be called consciousness.

Definition. Consciousness is the mental process that functions to create conscious awareness and conscious experiences.

It is important to note that any awareness that does not have the awareness of what phenomenal characteristics are like occurring is not conscious awareness and is called unconscious awareness (see section 3.2), such as unconscious awareness of blood levels of various substances (e.g., sodium, oxygen, and hormones), in which the mind is unconsciously aware of these blood levels and unconsciously reacts to them but never has awareness of what their phenomenal characteristics are like. Consciousness does not function to create this kind of awareness (unconscious awareness).

Also, it is to be noted that the definition does not define that consciousness is the mental process that functions to be aware of and experience all mental processes. Some mental processes are not accessible to consciousness, and consciousness can neither be aware of nor experience them [1]. These mental processes are called sub-conscious or non-conscious mental processes and are not included in the definition. Mental processes that consciousness can be aware of and experience are called conscious mental processes (not consciousness mental process, which is one distinct mental process), and it is only these mental processes that consciousness functions to be aware of and experience. To be noted also is that, because conscious mental processes are mental processes that the consciousness can be aware of with the awareness of what their phenomenal characteristics are like occurring and that the consciousness can experience, these mental processes must have phenomenal characteristics. That is all conscious mental processes must have qualia.

It is important to be aware that, in the literature, the terms conscious and consciousness are ambiguous terms, and can have various meanings [2-10]. They can be used to describe different mental phenomena, such as

  1. a mental state of being awake and sentient (such as, he lost his consciousness in the accident and became conscious after a while),
  2. a mental state of being aware of something (such as, he is conscious of the girl’s presence and her scent, or he is conscious of the pain in his body),
  3. a mental process that creates awareness and an experience of something (such as, one scientist believes that what creates the awareness and experience of the vision, sound, emotion, and thought is the consciousness), and
  4. a “command center” mental process that integrates other mental processes and enables them to function together (such as, another scientist believes that what functions to direct attention to something, keep concentration on that thing, and distribute information of that thing to other mental processes is the consciousness) [11,12,13].

Neurologists and general doctors usually use the terms conscious and consciousness in the first meaning. General people usually use the terms in the second meaning. Philosophers and some neuroscientists usually discuss the terms in the third meaning, and the hard problem of consciousness [2,3,9,14,15] is the problem about consciousness in this meaning also. The terms in the last meaning are used mostly by neuroscientists, and the Global Workspace theory [11,16,17,18] and the Global Neuronal Workspace theory [19,20,21] are about consciousness in this meaning also. Even in the last meaning alone, the terms are still ambiguous – it depends on one’s opinion what functions (directing attention, maintaining attention, distributing information, creating awareness, making decisions, etc.) are to be included into consciousness’s functions [22]. Therefore, one should be careful what the terms mean at that point when one reads, writes, or discuss these terms.

In this theory, the term consciousness will be used to mean a mental process that creates conscious awareness and conscious experiences because it is the only function that differentiates sentient beings from non-sentient beings and differentiates us from artificial intelligence. Without conscious awareness and conscious experiences, even the most highly integrated and very capable brain will function just like a present-day computer or robot. For other authors, the opinions may be that the term consciousness should also include some other integrative/command functions as described above, but then again, the opinions may vary on how many and exactly which of those integrative/command functions are to be included. Therefore, as the term consciousness as defined above suffices in discussions in this theory, it will be used as a working definition in this theory. This definition can be considered the minimum definition of consciousness; the wider definition is possible but not needed in this theory.

6.2. Consciousness neural process

As consciousness is a mental process, it cannot occur spontaneously by itself but must be part of some neural process (Theorem I). In this theory, this neural process will be called the consciousness neural process. From its properties, it can be predicted that some important characteristics that a consciousness neural process and its circuit must have are as follows:

  1. It must be an extensive network that connects with all neural processes that have qualia so that awareness and experiences of all qualia are possible. These neural processes are important neural processes: all external sensory perception neural processes, many internal sensory perception neural processes, language neural processes, all cognitive and executive neural processes (thinking, reasoning, planning, deciding, etc.), emotion neural processes, volitional movement neural processes, etc. But it is not connected to or not connected in the way that conscious awareness and experiences can occur with lower mental processes, which perform more basic functions, such as mental processes in the basal ganglia, brainstem, or cerebellum, so there is no conscious awareness and experiences of these processes.
  2. It must be able to read and/or synchronize with neural processes that have qualia so that it can get into the signaling states that signal the awareness and the experiences of the qualia. This is a must because it is only in these signaling states that conscious awareness and the conscious experiences of the qualia occur.
  3. It must have its signals fed back to itself so that it can be aware of itself and its function.
  4. Its signaling pattern must be a special signaling pattern (SSP, see section 5.1.2.) so that the quale of the conscious awareness and experience can happen.

As far as one can conclude from the evidence at present, it seems very likely that the Default Mode Network or Resting State Network [23-28], which includes the medial prefrontal cortex, posterior cingulate cortex, precuneus, hippocampal formation, parahippocampal cortex, retrosplenial cortex, posterior inferior parietal, temporoparietal junction, and lateral temporal cortex, with anterior medial prefrontal cortex and posterior cingulate cortex as the hubs, is the network of consciousness neural process when the mind is not concentrating on any specific task. This network overlapped with the network of Global Workspace theory proposed by Baars [11,16,17,18] and that of Global Neuronal Workspace hypothesis of Dehaene [19,20,21], which include the cortico-thalamic (C-T) core and a network of neurons with long-range axons densely distributed in prefrontal, fronto-parietal, parieto-temporal, and cingulate cortices. This network is found to be the consciousness neural process network when the mind is in the mode of attending to a certain specific stimulus. So, the exact neural network of consciousness, in general, is likely to be some form of a combination of the two networks, such as that proposed by Song [29].* It should be noted that the functions of the two networks are not mutually exclusive, that is, the two networks do not work alternately in the way that one is shut off completely while the other is working. For example, when the Global Workspace or the Global Neuronal Workspace is functioning, such as when attending a visual stimulus on a computer screen, the Resting State Network or Default Mode Network is still functioning, as evident by the fact that the subject is still aware of the background vision, the ambient sound, one own self, etc., although the awareness of these background stimuli becomes less intense and less acute. It is not that, while the mind is attending something, it is not aware of anything else at all, and everything else blacks out.

(* Presently, there are several other significant theories of consciousness [11,22, 30-44] which deserve much consideration and have been instructively reviewed [45,46 ], but it is not the intention of this Theorem to discuss this matter in details.)

To be noted is that consciousness is a conscious mental process, i.e., it can be aware of itself and can experience itself. And although consciousness appears to be of paramount importance in making us conscious, it is just one mental process among myriad other mental processes. Although it seems to be special in that it can create the phenomenon called conscious awareness and conscious experiences, other mental processes have their own special functions that are no simpler than creating conscious awareness and conscious experiences, such as creating visual perception from visual stimuli, creating emotion, creating language abilities, and creating intelligence that can solve difficult mathematical problems or unravel mysteries of the nature. Physically, consciousness is no different from other mental processes – it is just part of a neural process: the consciousness neural process. And it follows physical rules and has properties similar to all other mental processes, as described in section 1.1. Thus, although of paramount importance, consciousness is not an exceptional mental process in any physical way.

Conscious alertness and awareness

Functionally, it has been found that the network of consciousness neural process requires another neural network – the ascending reticular activating system (ARAS) – for its alertness or the level of its function. The ARAS is the neural network in the core of the brain extending from rostral pons to both thalami, and from there it sends extensive axonal projections to the cerebral cortex, including the consciousness neural network [48-51]. There can be no consciousness if there is no stimulation from the ARAS, even if the consciousness neural network is intact and able to function, such as in cases of extensive brainstem hemorrhage, infarct, and trauma. And the level of conscious alertness depends on activation from ARAS – the more activation, the higher level of alertness. This results in various conscious states, such as (from lower to higher level of alertness) physiologic sleeping, drowsiness, normal alertness, and heightened alertness.

On the contrary, if the ARAS is working normally but the consciousness neural process is not, there can be alertness without, with minimal, or with some awareness. The degree of impairment of awareness depends on how much the consciousness neural process is dysfunctional. For example, in cases of damages to the consciousness neural process from diffuse cerebral hypoxia, extensive bilateral cerebral infarcts, or diffuse cerebral cortical injury, the results can be various abnormal conscious states that range in severity of abnormal conscious awareness, depending on how much the consciousness neural process is impaired, such as (from mild to severe) acute confusional state, akinetic mutism, minimally conscious state (MCS), and vegetative state (VS) [52-58]. In the latter two categories, which are severe cases, the patients can open eyes and have some reflex responses, such as blinking, chewing, and yawning, but show no (in VS) or minimal (in MCS) signs of conscious awareness of self and the environment (by clinical testing or by special investigation such as EEG, evoked potentials, fMRI, etc.) [56-62].

Both of the two kinds of variable abnormality in consciousness show that consciousness is not an all-or-none phenomenon, but is a graded phenomenon, depending on both the strength of stimulation from ARAS and the functioning quantity of the consciousness neural process.

6.3. Theorem V

As proved in section 5.2., conscious awareness and conscious experiences are neither new physical entities nor novel non-physical entities – they are just special signaling patterns of the consciousness neural process. To briefly summarize how they occur: when the consciousness neural process reads the signaling pattern of a quale (such as a visual quale), it will process the received signals in its circuit and, when finished, will be in the signaling state that signals conscious awareness and a conscious experience of a quale. The signaling pattern of this signaling state is the special signaling pattern (SSP) that is the conscious awareness and the conscious experience of the quale. Because the SSP is the conscious awareness and the conscious experience of the quale, the conscious awareness and the conscious experience of the quale must inevitably occur. Thus, the consciousness neural process creates conscious awareness and a conscious experience by creating the special signaling pattern that is the conscious awareness and the conscious experience. But how can the special signaling pattern be the conscious awareness and the conscious experience? The answer is, because it is evident that it can be (as can be seen in billions of human nowadays and in the past), it must be basically possible for the special signaling patterns of the consciousness neural process to be the conscious awareness and the conscious experiences of qualia. It is a brute fact: some signaling patterns – the special signaling patterns of the consciousness neural process – can be conscious awareness and conscious experiences of qualia. This theory states this as theorem V:

Theorem V: Conscious Awareness and Conscious Experiences are the Special Signaling Patterns of the Consciousness Neural Process.

If we consider the matter in general, this is not very surprising or improbable because there have been myriad kinds of neural processes with myriads kind of signaling patterns for various neural functions in various parts of the nervous system since the nervous system appeared in this world hundreds of millions of years ago. The nervous system has evolved neural processes with specific signaling patterns to perform numerous kinds of diverse activities: to maintain basic, vital functions (to control  breathing, heart rate and rhythm, blood pressure, body temperature, etc.), to keep various blood constituents (water, electrolytes, sugar, lipid, hormones, etc.) within normal ranges, to process sensory signals (light, sound, chemicals, etc.), to do cognitive functions (analyze, memorize, recall, decide, do language function, etc.), to control the functions of its effectors (smooth muscles, striated muscles, endocrine glands, etc.), and so forth. All of these need evolved specialized neural processes with specific signaling patterns of their own. The consciousness neural process is just one neural process with the evolved specialized function of creating conscious awareness and conscious experiences. It is just the fundamental nature of this universe that this is possible: some evolved SSPs can be conscious awareness and conscious experiences, and some neural processes – the conscious neural process – can evolve to create these SSPs.

The physical question of “By what neural circuits and by what neural mechanisms can the consciousness neural process create conscious awareness?” is being studied by many neuroscientists, and the answers are emerging, such as joint parietal-frontal-cingulate activation, cortico-cortical or thalamo-cortical γ-band oscillations, cortical neural synchronization or top-down recurrent, reentrant, or resonant activities between neural processes underlying conscious perception [50,63-72,79], the attractor activity in networks of pyramidal cells in the cerebral cortex [73,74,75], or the operational architectonics [76,77,78]. As the issue is very complex and lengthy, I would like to refer the readers to some of the references [5] that are quite revealing for more information.

6.4. Effects of consciousness 

Like qualia, which are proved in section 5.4. to have some physical effects, consciousness has some physical effects. This can be proved as follows. Consider two integration-center mental processes in Figure 6.1. The integration-center mental process A functions without consciousness, that is, it receives information from various mental processes, analyzes them, distributes appropriate information to appropriate mental processes, enhances and maintains input from a certain mental process while suppressing input from unrelated mental processes, etc., all without consciousness – no conscious awareness and experiences occur in its operations – like the cerebellum or present-day computers. On the other hand, the integration-center mental process B performs identical functions too but with consciousness – conscious awareness and experiences of its processes and other mental processes occur in its operations. As these two mental processes involve different phenomena with different description, they have different information. Because they have different information, they require different signaling patterns (because signaling patterns of neural processes are the neural processes’ information, see D6. -D8. in Chapter Introduction and Definitions) in their neural processes. Consequently, the physical effects on other neural processes must be different, at least because of the differences in processing different signaling patterns.

Figure 6.1

So, the integration center without consciousness will have different effects from the one with consciousness. At present, there is not enough evidence to state conclusively what these different effects are. But as evolving the integration center by adding a new feature (in this case: consciousness) must cost a being some resources (material to build the circuit, energy to maintain the process, time to handle additional signals, etc.), if the new feature (in this case, consciousness) does not yield any benefits to the being, it will be a disadvantage for that being. This will be true for its species as a whole, too. Its species is expected to be losing from this disadvantage and will become extinct in competition with the species that is similar but does not have consciousness. But this kind of extinction has not happened to human beings, who definitely possess consciousness, and to many high-level animal species that probably have consciousness [80-87]. On the contrary, these species seem to be thriving and dominating in the evolutionary process. Therefore, it can be deduced that consciousness must yield some beneficial effects to the beings that possess it. Similar to effects of qualia on perception, it is probable that consciousness augments the functions of the integration-center mental process to become more effective [88].

But why does it have to be consciousness to gain these augmented effects?

This question is similar to the one regarding qualia, which has been answered in section 5.4.3. The answer in the case of consciousness will be very similar. It will be repeated here again with some modifications and in an abridged form. (If already content with the answer in 5.4.3., the reader may just as well skip the next three paragraphs to the next question.)

Before augmentation the functions of the nervous system by creating consciousness emerged, the nervous system had been augmenting its functions with other means all along since it appeared on this planet – by developing more and more complex and more and more capable nervous system – notwithstanding the absence or presence of consciousness. Even after consciousness had emerged, other parts of the cerebral cortex that function without consciousness did not stop evolving: they have been continuing to evolve to be more complex and more capable [89], resulting in higher intelligence, more language facilities, more manual skill abilities, etc. Even the cerebellum and other parts of the brain have proved to continue to co-evolve with the cerebral cortex [90,91,92] (which is the seat of consciousness) all the time, even if they do not have consciousness.

Creation of consciousness is just one possible path in the nervous system evolution. Consciousness emerged in this world simply because, at a certain stage in the nervous system evolution, it was possible – the neural processes had advanced enough to evolve the new kind of neural processes that was capable of creating consciousness. After consciousness began to appear in this world, it has been selected to persist up to the present time, possibly because it yields some advantages to the animals that possess it. That is why today it still exists in humans and probably in some other animals too [80-87]. And consciousness emerged to no other causes than evolution; that is why it took more than two billion years after life had appeared on earth and hundreds of millions of years after the nervous system had emerged before it could evolve into existence.

It remains to be seen whether creating consciousness is the end of this evolutionary path or whether neural processes with consciousness can evolve further into new kinds of neural processes with new capabilities that are even more phenomenal than consciousness. To augment its functions, the nervous system has been evolving many kinds of neural processes all along. The generation of consciousness is thus not the necessary path, the most effective path, or the final path, but just one possible path, in augmenting the nervous system functions.

Then, why not augment all mental processes’ functions with consciousness? Why augment only some mental processes?

This question is similar to the question regarding qualia in section 5.4.4., which was answered concisely there. The answer in this chapter will be a detailed answer.

As noted in section 3.4, mental processes that have conscious awareness and experiences are mental processes that involve the final-stage perceptions of all external sensations and some internal sensations, cognitive perceptions (of space, time, self, non-self, etc.), cognitive and executive functions (thinking, recalling past events, planning, deciding, language dealing, etc.), emotion, and volitional motor control. The other mental processes, which comprise the majority of all mental processes, do not have conscious awareness. For example:

– No conscious awareness and experiences of blood levels of O2, CO2, Na, K, other electrolytes, various hormones, and other blood constituents even if some mental processes (unconsciously) sense these levels in details and react to them all the time. We never have conscious experiences of what it is like to have these blood constituents at various levels (such as what it is like to have blood sodium level at 135, 145, 155, etc. mEq/L) until they are significantly out of their normal ranges. Then we will experience feelings of sickness not because we have sensory organs to consciously sense the abnormal levels but because various cells in the body become dysfunctional and because the nervous system can have conscious awareness of these non-specific abnormalities in the body.

– No conscious awareness and experiences of blood pressure in our arteries even if some mental processes (unconsciously) sense this pressure in details and react to it all the time. We never have conscious experiences of what it is like to have blood pressure at 120/80, 160/90, 210/110, etc. mmHg, until it far exceeds the lower or the upper limit, then we can sense something wrong. But, then again, we feel it not because we have the sensory organs that can consciously sense it but because some cells in the body become dysfunctional and because the nervous system can have conscious awareness of these non-specific abnormalities in the body.

– No conscious awareness  and experiences of the functions of basal ganglion in controlling the posture, muscle tone, etc. and no conscious awareness and experiences of the cerebellar functions in coordinating and fine-tuning motor movements, either. We never know what it feels like to control these aspects of motor function: to contract this one myofibril or that one myofibril appropriately, to contract all the involving agonist and antagonist muscles correctly, to contract an intrafusal muscle fiber appropriately, etc. All we know is we consciously control the purpose of motor movement in general, and the details in controlling the movement, which involves a lot of muscles of all types all over the body simultaneously, occur unconsciously by the functions of the basal ganglion, some brainstem nuclei, and the cerebellum.

– No conscious awareness and experiences of the functions of the autonomic nervous system, gastrointestinal nervous system, and many low-level mental processes in the brain. We never feel what it is like to control the contractions of our pupils or our guts, what it is like to secrete sweat or hormones, or what it is like to analyze raw visual data at the primary visual areas when the correct image with correct shape, color, brightness, movement, etc. has not yet been formed.

Still, without conscious awareness and experiences, these mental processes can communicate and carry on their functions in concert with each other effectively. Therefore, analyzing information and distributing information between mental processes do not require consciousness. Even attention and concentration (or directing mental processes to and keeping mental processes on some stimuli) must be able to be done without consciousness as well because, evidently, they must be occurring in the cerebellum and other brain structures too so that they can select and hold on to their tasks until they can finish their processes. Now, the obvious questions are: why do these mental processes not need consciousness in their functions; what is the difference between them and mental processes that have consciousness?

It can be noticed that all of the above examples of mental processes without consciousness are mental processes that are related to internal functions of the body, early-stage processing of external information (such as processing raw signals that arrive at the primary sensory areas), or routine/programmed functions (such as basic motor movement or well-learned movement). The variation ranges of these internal parameters, such as levels of blood constituents, arterial blood pressure, muscle spindle tension, the speed of muscle contraction, etc., are limited. The body will try to maintain these internal parameters within normal ranges. If these parameters exceed the normal ranges too much, the organism will die. Thus, a living organism will face only limited values of these parameters and never has to cope with unlimited values of these parameters. The same is true for external parameters also. The variation ranges of specific external signals, such as light, sound, touch, etc., that reach the brain are limited. If external parameters exceed sensory organ limits, such as wavelengths above or below visible wavelengths or sound frequency above or below audible frequencies, they will not be registered by the sensory organs, and their signals will not be sent to the brain. Thus, external sensory signals that are presented to the brain are limited within some ranges. As the number of values to be dealt with (both internal and external situations) is limited, separate or partially separate hardwiring of the nervous system to manage these parameters is sufficient. And it is evident that this kind of hardwiring is possible – the early-stage sensory perception of all sensory modalities, the cerebellum, brainstem, basal ganglion, thalamus, the autonomic nervous system, etc. have evolved complex neural circuits to do what they are doing efficiently. There is no need for each of these systems to become conscious. If unnecessary conscious awareness exists in these systems, it would be a disadvantage to the being because it would have to waste its resources to build, to maintain, and to operate such a surplus process.

In contrast to the situations in the previous paragraph, the outside world poses unlimited challenges to an organism. The organism receives information of these challenges through its external sensory organs (i.e. eyes, ears, skin, echolocation organ, magnetism sensing organ, electricity sensing organ, etc.). Although, via any sensory organ, an organism can receive any single sensory stimulus in some limited physical ranges only (such as in limited visible light spectrum or limited sound frequency spectrum, as discussed above), the whole sensory input via any sensory organ is a composite of innumerable separate stimuli in almost indefinite combinations. This complex composite, which the brain has to interpret, can thus vary in details virtually infinitely (such as virtually infinite possible images and virtually infinite possible sounds). Moreover, the different situations arising from the combination of these complex composites of all sensory modalities are practically limitless. For example, the situation with a visual image of a tiger charging with roaring sound is different from the situation with a visual image of a ripening apple with a sweet smell, and there is an infinite number of such different complex situations. So, hardwiring the brain circuits to respond specifically to each of these virtually limitless situations must require a very, very huge brain or is biologically impossible at all.

Another way to cope with this situation is to evolve a broadly adaptable nervous system that does not depend on fixed hardwiring of neural circuits alone, but is also able to make use of information gathering and processing: gathering encountered information, extracting the essence of each information, storing it, retrieving it, and dealing with it cognitively (i.e. by processes of forming possible scenarios, retrieving experiences in the past, comparing available choices, using rules that have been learned, etc.). This is similar to the computer, which has fixed limited hardware modules but can do versatile operations (text processing, data managing, drawing and painting, video recording and playing, simulating scientific processes, etc.) by using software programs (these are learned processes in living beings) and data files (these are memories in living beings), without having a separate hardware module for each operation. The main board of the computer would be very much bigger if there had to be separate hardware modules for all the separate operations.

Thus, the cerebral cortex has evolved to be a broadly adaptable system that does not depend on fixed hardwiring of neural circuits alone but is also able to make use of information gathering and information processing. But this system requires an integration center that can coordinate signal communications between several cortical areas:  those involved in the final-stage perceptions of all external sensations and some internal sensations, cognitive perceptions (of space, time, self, non-self, etc.), other cognitive and executive functions (thinking, recalling past events, planning, deciding, language dealing, etc.), emotion, and volitional motor control. It can certainly operate without consciousness, as is evident by the fact that the computer and the cerebellum can also do this kind of integrations without consciousness, but as shown in section 6.4., the integration center without consciousness will have different effects from the one with consciousness, with the one with consciousness have potentials to add something beneficial effects to the system. Thus, creating consciousness in such a vital system, with conscious awareness of all important mental processes, can yield critical advantages to the organism. It can enhance perception, cognition, emotion, memory functions, volitional motor functions, etc. It is likely that because perceiving the situation in the outside world effectively, analyzing them and forming responses to them effectively, and executing purposive motor movement effectively are the most crucial mental functions of the being, it is beneficial and advantageous to augment the mental processes that perform these crucial functions with a novel function: consciousness. This is why consciousness evolved to occur in these mental processes and this is why some mental processes have consciousness while some do not – consciousness in some mental processes is beneficial and can yield advantages while consciousness in some mental processes is unnecessary and can create disadvantages.

6.5. The hard problems of consciousness

The hard problems of consciousness can be answered similarly to those of qualia (see section 5.5.) because consciousness is just another mental process that has qualia. The hard problems of consciousness are basically the hard problems of its quale because other aspects of consciousness, such as what the exact neural circuit that can function to create consciousness is, are “not hard” in the sense that they can theoretically be found out eventually by scientific investigations. Without its quale, the consciousness neural process is just a complex neural process that is not functionally different from complex integrated circuits of computers or robots nowadays. However, there are some differences in the answers to the hard problems because consciousness is a mental process, but qualia are mental phenomena. So, the answers have to be adjusted as follows:

6.5.1. Why does consciousness exist?

Consciousness exists in this universe because it is fundamentally possible to have consciousness in this universe. And it exists in the nervous system – in the consciousness neural processes – because, in this universe, it is fundamental in the neural process’s nature that some kinds of them can create conscious awareness and experience. Whether consciousness exists in other processes, such as electronic processes of electronic circuits in computers or robots, or in other processes, such as weather systems, population systems, or dynamic energetic processes in the star, remains to be investigated.

6.5.2. Why does consciousness occur?

Consciousness occurred because, at some evolutionary stage about 520 – 315 million years ago (see footnote 3 in 5.5.2), it was possible for the nervous system, which was advanced enough then, to evolve new neural processes that were capable of creating conscious awareness and experiences Thus, consciousness occurred simply because it was evolutionarily possible for it to occur.

Consciousness still occurs today because there are neural processes that are capable of producing them functioning. Evidently, that these kinds of neural processes still exist today means that they have been preserved in the evolutionary process since they appeared in this world. This, in turn, implies that the consciousness (which these kinds of neural processes produce) must yield some beneficial effects that increase the chance of survival of the species that possess it. Thus, consciousness still occurs today because it must somehow help increase the chance of survival of the species that possess it.

6.5.3. How does consciousness occur?

Consciousness occurs by the functioning of a specific neural process (the consciousness neural process). Specifically, consciousness occurs by this neural process circulates its signals in a specific pattern – the special signaling pattern – which, by its fundamental nature, can be conscious awareness and experiences. The exact characteristics of this kind of neural process and its special signaling pattern are being actively investigated by neuroscientists. Some of them have already been discussed in section 6.2. above.

6.5.4. When does consciousness occur?

As discussed in 6.5.2., consciousness occurred in this world around 520 – 315 million years ago when the nervous system was advanced enough to evolve the neural process that was able to produce conscious awareness and experiences – the consciousness neural process. After that, consciousness occurs whenever the consciousness neural process functions.

6.5.5. Why can there not be just nervous systems without consciousness?

There can be just nervous systems without consciousness, and this had been the case for a long time – hundreds of millions of years – since the nervous system had appeared on this planet to the time that evolving neural processes became advanced enough to produce conscious awareness and experiences. When that time came, consciousness emerged simply because it was possible, and it persists in the evolutionary process probably because it yields some beneficiary effects to animals that possess it.

6.5.6. (a) Why can the consciousness neural process not produce conscious awareness and experience but still preserve the same particular effects?

(a) Because it cannot do that – those particular effects result from conscious awareness and experience themselves. When the consciousness neural process produces conscious awareness and experience of something, it produces some specific SSP, which is the conscious awareness and experience of that thing. This specific SSP is what yields those particular effects to other neural processes. Therefore, the consciousness neural process cannot have those particular effects without producing this specific SSP, which is the conscious awareness and experience.

6.5.6. (b) Why does nature not augment the nervous system with a neural process that is identical to the consciousness neural process in physical effects but that is without conscious awareness and experience?

(b) Because that is not possible. Like the situation in (a), to be identical to the consciousness neural process in physical effects, it must produce the SSP because the SSP is what that yields the particular effects. But if any neural process produces the SSP, conscious awareness and experience must occur, unavoidably.

6.6 Consciousness in other beings, other entities, or other mental states

Do animals have consciousness?

Because similar neural processes have similar information processing parts and because the information processing part of a neural process is the mental process, similar neural processes have similar mental processes. Therefore, any animals that have similar neural consciousness processes to those of humans have similar consciousness mental processes – or, in short, similar consciousness. Animals that have similar brain structures and processes to ours, such as mammals (chimpanzees, elephants, dolphins, dogs, etc.) are likely to have fairly similar consciousness to ours. Animals that have less similar brain structures and processes to ours, such as reptiles or amphibians (crocodiles, frogs, etc.) are likely to have less similar consciousness to ours. Animals that have very different brain structures and processes from ours, such as arthropods (ants, bees, flies, etc.) or cephalopods (octopus, squid, nautilus, etc.), may have different kinds of consciousness from ours (if they do possess it at all) [47,85-87]. This can be definitely answered if the kind of neural circuits and signaling patterns that create consciousness in humans and the probable consciousness neural circuits and their signaling patterns in other animals can be identified and compared.

Do computers and robots have consciousness?

As computers and robots have parts that function similarly to parts of the nervous system of animals – sensors (mouse, keyboard, camera, microphone, etc.), central processor and controller (computer motherboard, robot mainboard, etc.), and effectors (display monitor, speaker, robotic arm, etc.) – and they use electrical signals in processing information and communicating between these parts and thus have electrical signals representing various kinds of information circulating in their circuits, it is logical to speculate that there might be qualia phenomena occurring in their systems because some of their signaling patterns might be qualia like some of human neural processes’ signaling patterns – the special signaling patterns. At present, it cannot be answered definitely whether qualia occur in their signaling processes because we still do not know what kind of signaling patterns can be qualia.

However, if qualia do occur in the computers and/or robots, they definitely have no physical effects on any of their circuits because, evidently, all their circuits still work in the expected way that they are designed to do. It has never been found that the circuits in the computers and robots do any operations that are not pre-designed in them. And it is definite that present-day computers and robots do not and cannot have conscious awareness and experiences of qualia (even if qualia occur in them). This is because to have conscious awareness and experiences of qualia needs specific, dedicated circuits to perform these specific functions and manage the new information that occurs in the process. But there are no such circuits in the present-day computers and robots; all the circuits in their motherboards or mainboards are built to do some specific tasks else that are already predefined, such as the summation of two digits, the computation of transcendental functions of some digits, and the generation of signals to control other parts: screen monitor, disc drive, mechanical motor, etc. None is built to be aware of and experience qualia that may occur in their circuits, and none is built to be aware of and experience itself either. Therefore, it is definite that present-day computers and robots do not have consciousness, that is, do not have conscious awareness and experience of anything. Similarly, this conclusion is true for all other electronic devices or any device that processes information of the present day: a thermometer, a mobile phone, an industrial robot, an automated industrial machine, etc. This is in agreement with some theory of consciousness such as Integrated information theory (IIT) [93,94,95].

Although some principal characteristics of a neural circuit that can generate consciousness are obvious, as outlined in section 6.2., the exact details of the circuit are not yet known at present. Theoretically, if they are known and if the possibility of having consciousness is not restricted to only biological processes but extends to electronic processes, then computers and robots that have consciousness can be built. This is in accordance with the principle of organizational invariance of Chalmers [96]. And some theories of consciousness, such as Integrated information theory (IIT) [93,94,95], have already proposed interesting ideas about these kinds of consciousness.

When we are asleep in NREM stages, under general anesthesia, or in a deep coma, do we have consciousness?

Obviously, under those conditions, the consciousness neural process is not functioning at the alert level, and there is no signaling pattern that is alert consciousness; thus, no alert consciousness mental process occurs, and we, therefore, do not have alert consciousness in such conditions. However, although the consciousness neural process is not functioning to produce alert consciousness, it is not dead and is still functioning at the sleep or depressed level, and the state of no alert-consciousness will be only temporary if there is no fatal condition involved. So, physiologically, consciousness can function at various levels, not only at the alert level. And it can be considered that we still have consciousness, but not at the alert level, when we are asleep in NREM stages, under general anesthesia, or in a deep coma.

When does consciousness appear in a being?

Consciousness does not come suddenly once the brain begins to form in a fetus, nor does it come when an infant is born. As consciousness is a mental process that occurs from the consciousness neural process, it will appear when the consciousness neural process circuit is mature and begins functioning. Obviously, it cannot appear all of a sudden in the fetus but develops gradually as the consciousness neural circuit and process mature little by little. This is true for a person who slowly wakes up from sleep or gradually recovers from general anesthesia, cerebral concussion, hypoglycemia, etc. – consciousness returns gradually, not reappears suddenly like the electric light that is switched on. Consciousness is a mental process that can function not in an all-or-none manner but in various graded levels, as discussed above.

6.7. Predictions

  1. It will be found that the consciousness neural processes have connections to all neural processes that have qualia and that it has its signals fed back to itself.
  2. It will be found that the signaling patterns the consciousness neural process, when it functions to be aware of and experience something, are of special signaling pattern types.
  3. As conscious awareness and conscious experiences are special signaling patterns of the consciousness neural process, all predictions that are valid for the special signaling pattern of the consciousness neural process in any event or experiment will also be valid for conscious awareness and conscious experiences. For example, if the predictions in an event or experiment involving the special signaling patterns of the consciousness neural process are that the special signaling patterns will disappear, reappear, change, etc., the same predictions will be true for the conscious awareness and conscious experiences too.
  4. Conscious awareness and conscious experiences can be created, manipulated, measured qualitatively and quantitatively, monitored, or destroyed by performing the respective action to the special signaling patterns of the consciousness neural process.

6.8. Remarks

This Theorem will be invalidated if there is evidence showing that there are properties that conscious awareness or conscious experiences have but special signaling patterns of the consciousness neural process cannot have.


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