Mind Operational Semantics and Brain Operational Architectonics: A Putative Correspondence

INTRODUCTION

Despite allowing for the unprecedented visualization of brain functional activity, modern neurobiological techniques have not yet been able to provide satisfactory answers to important questions about the relationship between brain and mind. Precisely, in the specific field of the studies of the relationship between brain and reflective consciousness [1], where the natural human language plays an important role, there is still no common consensus among neuroscientists even about which cortical areas (or neural processes) are involved in the processing of, and phenomenally constituting, the meanings of words. For example, on the basis of both lesion and positron emission tomography (PET) data, Tranel and Damasio [2] emphasize the role of the left inferior and middle temporal gyri, while based on PET and electroencephalographic (EEG) data, Posner and Di Girolamo [3] argue for semantic processes in left inferior frontal areas. At the same time, based on magnetoencephalographic (MEG) evidence, Salmelin, Helenius, and Kuukka [4] claim that the left superior temporal lobe is relevant for word semantics; and Skrandies [5] reports EEG studies highlighting the importance of the occipital lobes in distinguishing word meanings, whilst Pulvermüller [6] stresses the importance of primary motor, premotor and prefrontal areas for word-meaning processing.

As Pulvermüller has properly observed referring to the difficulty of modern neurobiological techniques to localize the cortical areas involved in semantic processing, probably this shortcoming of cognitive neuroscience is partly due to the lack of an adequate theoretical apparatus: “In spite of the undeniable progress made possible by empirical results obtained with newly introduced techniques, it is likely that theoretical advances are necessary as well” (Ref. [7], pp. 47).

In our opinion, in order to identify the brain structures and mechanisms responsible for the production of higher-order mental phenomena such as thought and semantic processing, a theoretical framework proposing what to look for and at which level to do it is the necessary guide. To be adequate, this theoretical framework should be able to connect the phenomenal aspects of consciousness and their underlying brain mechanisms. Using Revonsuo’s words (Ref. [1], pp. xvi), one “should take very seriously both the subjective psychological reality of consciousness and the objective neurobiological reality” in their intimate connectedness within a single integrated continuum.

Indeed, only an adequate theoretical apparatus can provide cognitive neuroscience with the level of description and explanation necessary to carry out its investigations. In general, cognitive neuroscience is interested in discovering how the brain makes possible and realizes cognitive phenomena such as language, consciousness, attention, memory, etc.: in a word, to have a mental life. In order to achieve this aim, cognitive neuroscience usually tries to find out where in the brain, in which brain areas, a particular cognitive phenomenon is located; what kind of neuron circuit implements it; at which point in time the phenomenon takes place compared to the neural process. Cognitive neuroscience tries then to give an account in physical terms of cognitive, mental phenomena.

It is quite easy to realize that such an account cannot be given without having first formulated a theoretical model that explains how cognitive phenomena are produced, what they consist of, and, more in general, how our mind works. Indeed, in order to identify the brain structures and mechanisms responsible for the production of cognitive phenomena, one needs a criterion by means of which one understands where, what, how and when to look for and to observe. The physical field can be subdivided in so many different levels (the micro-level of the atoms and sub-atomic particles; the medium-level of cells and neurons; the macro-level of the neuronal assemblies and nets of these assemblies, etc.), and observed from so many different angles (as an isolated unit, as a composite system, as a dynamic structure, etc.) that without a criterion or guide for deciding where, what, how and when to observe, one cannot even start a research. Where should one address it? What should be the more appropriate level of observation of the physical phenomena: the level of the atoms composing neurons, the level of neurons, or the level of the assemblies of neurons? How, and on what basis, could one explain the relationships between the various elements composing each physical level? What criterion should one adopt to analyze the relationships between the different physical levels? More in general, how can one explain the transition from the physical level to the mental one?

What should this theoretical model look like in order to adequately support both cognitive (phenomenal, psychological, linguistic, neuropsychological, neuro-linguistic) data and their neurophysiologic underlying mechanisms? We believe it should be an operational model, that is, a framework centred on the notion of “operation”. Let us see the main reasons that led us to believe this:

1. Mental phenomena are not mere copies of the external world, but are the product of the subject’s activity. As such they can best be described and analyzed in terms of the operations performed by the subject’s mind to produce them.
   In general, there is clear evidence in many experiential fields that even basic mental phenomena such as perception, attention and memory do not simply reflect what is “out there”, but are the result of specific (voluntary and involuntary) cognitive processes of the subject. For example, well known phenomena in time perception, such as “prior entry” [8, 9] and “temporal displacement” (Zeitverschiebung) [10, 11] clearly show that the way the subject perceives the sequence of events is determined not so much by the objective, physical sequence of the events, but by cognitive factors: the way the subject deploy its attention; whether the sequence of events occur within the so called “phenomenal present” [11], which is strictly linked to specific cortical rhythms [12]; and so on. Space perception is similarly determined by cognitive factors [13]. Moreover, very basic sensations such as pain and pleasure exist which certainly do no represent things and objects of the outside world [14].
   More specifically, the fact that mental phenomena are not mere copies of the external word is testified by higher-order mental phenomena such as reflective thought, conceptualization and imagination. Indeed, it is always possible to think about, describe, categorize or imagine even the simplest physical situation or object in two or more different ways, and two or more different situations or objects in the same way. Linguistic syntax is nothing less than the most evident way human beings have of bringing forth and realizing this, by variously linking, combining, re-combining and dividing phenomenal elements in various ways.
   What all this shows is that the mind does not so much passively duplicate the external world, but rather actively selects, discards and combines sensory, memory and conceptual data according to both inherited and acquired cognitive principles, in order to satisfy the subject’s personal motivations, objectives, and attitudes, as well as social and cultural constraints and habits. The human mind is first and foremost an “operating mind”.
2. As Ceccato has extensively shown in his work [15-19], what allows one to relate the mind and the brain, the mental field and the physical field - and consequently to compare them, as well as distinguish the former from the latter - are the concepts of activity and operations.

Mental activity (at least, the conscious one; see Ref. [20]) is characterized by the fact that its products coincide with the activity itself, in the sense that they last and are present only as long as the activity itself takes place. Let us consider, for instance, the thought of a burning tree: the thought (that is, the product of your mental operations) is present in the mind only as long as you think about it, and decays as soon as you stop thinking about it (that is, when you stop performing those specific mental operations).

Physical activity in the physical world, on the contrary, is characterized by the fact that its products survive the activity itself, and remain quite visible even after the activity is over: when we burn a piece of wood, we can see the product of the physical activity (the ashes) quite clearly even after it has ended.

The intimate connectedness between consciousness and neurobiological reality mentioned by Revonsuo [1] can then be found by utilizing the concept of “operation”: by means of it, we can capture, on the one hand, the kind of activity the mind performs when producing conscious mental phenomena, and, on the other hand, the physical, brain activity that is necessary to support mental activity.

Therefore, the most proper way of describing higher-order mental phenomena is by looking for and analysing the operations producing them, that is, by adopting an operational approach (for a more detailed discussion, see Ref. [21-27]). In this sense “operation” stands for the process or series of acts that are limited in time. This provides a basis for discussion of the relative complexity of operations, where there is a more complex operation/operational act that subsumes the simpler ones [27, 28].

Once an operational theory of mental phenomena in general and linguistic thought in particular is developed, it becomes possible to look for the neurophysiological basis of the operations producing them. Neurophysiological research will then be provided with a theoretical framework capable of guiding its investigations in a reasoned and methodical way. In turn, neurophysiological research will have the possibility of either confirming or falsifying the theorized postulates, and in the latter case it will lead theoreticians to modify their hypothesis, or adjust their analyses.

As Silvio Ceccato [15, 18] argued many years ago, only an operational model would be able to provide a suitable and viable criterion capable of directing the research investigation of what is considered to be the physical substratum of the mind: the brain. In fact, by analysing and considering our conscious mental world as a hierarchy of carefully organized self-presenting phenomenal patterns (which are both the object and the act/operation at the same time [1, 29]), produced by the activity of some physical system (the brain as a whole, or its parts), it is possible to assign to every single neurophysiological operation some mental property or pattern. In this way, the road is open to the systematic and detailed research of the physical (neurophisiological) basis of the phenomenal world: by subsequent and finer and finer manipulations of the physical brain substratum, one can empirically determine and isolate the system(s) that is (are) responsible for the instantiation of specific phenomenal features or patterns. The opposite strategy is also possible, that is, firstly isolating higher-order mental phenomena such as thought and semanticprocessing (or some other phenomenal pattern of subjective experience) and secondly trying to identify the neurophysiological pattern that is responsible for them or accompanies them.

The notion of operation, then, is the fundamental and central one in bridging the gap between brain and mind: it is precisely by means of this notion¹ that it is possible to identify what at the same time belongs to the phenomenal conscious level and to the neurophysiological level of brain activity organization, and mediates between them [27, 30].

In this article, we will present two different but complementary operational approaches to mind and brain: Operational Semantics (OS) and Operational Architectonics (OA). These two approaches had a completely independent origin, and belong to two different fields of research. OS, which was put forward by Benedetti and Marchetti following in the footsteps of Ceccato [16-19], is essentially based on introspection and the analysis of linguistic data. This approach, therefore, can be classified between Cognitive Psychology and Linguistics. Among other things, OS has led to the formulation of an operational theory of the nature and structure of linguistic thought, that is, of the kind of reflective thought that lies at the basis of human language, and of which human language is the expression.

OA, on the contrary, is based on the joint analysis of cognitive and electromagnetic (EEG and MEG) data. This approach originated from the work of Kaplan [31-33] and was further modified and developed into a complete theoretical framework by Andrew and Alexander Fingelkurts [26-28, 34-36]. According to this theory, whenever any pattern of phenomenality (including reflective thought) is instantiated, there is a neurophysiological pattern of appropriate kind that corresponds to it [30, 37]. These patterns (expressed as virtual operational modules) are brought into existence by joint operations of many functional and transient neuronal assemblies in the brain.

The aim of this theoretical paper is to show that these approaches are correspondent to each other through the shared notion of operation, which is central for the higher-order reflective thought/language (OS approach) and the functioning of brain (OA approach). In this paper, firstly, we will consider briefly the main principles of both theories. Secondly, we will illuminate what the supposed correspondence between them could be. And thirdly, we will consider the main implications deriving from the combination of these two approaches, namely the possibility of experimentally and empirically verifying by means of the neurobiological approach the hypotheses put forward, and the analyses performed, by the introspective-linguistic approach.

OPERATIONAL SEMANTICS (OS)

Since two theories (OS and OA) and their possible correspondence have to be introduced in the restricted space of an article, only the essential outlines of OS are shown here. A more in-depth introduction can be found in the main references [20, 23, 38]. The difference between this kind of semantics and the other kinds of semantics has been variously described: Benedetti [38] for example outlines the difference between OS and Natural Semantic Metalanguage [39-46]; Marchetti [20] outlines the difference between OS (which he also calls Attentional Semantics) and Logical-philosophical Semantics (put forward by authors such as Frege, Carnap, Tarski and Montague) and Structural Semantics (developed by authors such as Hjelmslev, Martinet, Greimas and Saussure); Marchetti [47] highlights the difference between OS and the kind of cognitive semantics put forward by Leonard Talmy. The difference between the principles inspiring OS and the other kinds of semantics is also highlighted by Ceccato & Zonta [19], who describe the difference between what they call Operative Linguistics and Structural Linguistics, and by Vaccarino [48], who extensively deals with the relationships between his Constructivist Semantics and the other kinds of semantics. Oliva [49] describes the differences between Operative Linguistics and the other main linguistic theories. Finally, and in order to let the reader better understand the theoretical innovations introduced by OS, it has to be noticed that OS differs substantially from the majority of recent psycholinguistic studies (for an extensive review, see Ref. [50, 51], not only for the fact that it primarily deals with, and privileges, the semantic aspect of language over the syntactic one, but also because it offers a functional model that could be applied equally well to the comprehension stage of language as to the production stage of language: in this sense, OS represents in our view an important improvement on , and integration to, current psycholinguistic studies.

As everybody knows, thought is not accessible with objective methods. It is accessible only subjectively through first-person perspective or, indirectly, by means of language. However, what is accessible is only the content of thought, not its mechanisms [1]. These mechanisms are shrouded in a deep mystery. Neural Science, despite its progresses, does not seem to be going to reveal this mystery (at least at present). OS proposes to study these mechanisms by adopting some new fundamental theoretical presuppositions and a methodology, which is both introspective and linguistic. What OS allows us to study is the higher-order reflective linguistic thought, that is, what language is the expression of (for the sake of simplicity, from now on we shall use the expression “linguistic thought”). Linguistic thought, despite being just one kind of thought, is nevertheless the prevalent one, at least in the human being who has already learnt to speak.

We believe that the best way to introduce OS is exactly to consider language itself. So, let’s take a fragment of language at random. For example, the beginning of one of the most famous books in the world: “Pinocchio”.

Once upon a time there was…

─ A king! ─ my small readers will say at once.

No, children, you are wrong. Once upon a time there was a piece of wood.

It was not a luxury wood, but a simple stack piece, one of those pieces we use to put in stoves and fireplaces in winter to light fire and to heat rooms.

Every discrete element of language, that is, every word, designates at least one meaning (in many languages, many single words designate more than one meaning together, like, for instance, the basic meaning plus the plural). Therefore, each word designates one (or more) “atoms” of thought. Let’s ask ourselves what these “atoms” are, what their nature is. As far as their nature is concerned, first of all it seems that the meanings of words can be divided into at least three categories.

1. In the passage we have chosen, there are words that, at first sight, seem to designate something physical (or, at least, mainly physical). These words are: “children”, “wood”, “stack”, “stoves”, “fireplaces”, “winter”, “[to] light”, “fire”, “[to] heat”, “rooms”. It is easy to realise that such words are so many that they make up probably most of the lexicon of any language.
   If we consider this class more in depth, however, it does not seem homogeneous. Words such as “robin”, “bird” and “animal”, for instance, seem all to belong to this class, but certainly they express an increasing level of “abstraction” (therefore, something mental). Words such as personal pronouns (“I”, “you” etc.), even if they undoubtedly designate something physical, are certainly more “abstract” than the names of the people they indicate in turn, for example “John Smith”. But, apart from these considerations, what we want to highlight is that there is a big class of words that have an evident and important reference to something physical.
2. Then, there is another class of words that indicates things that we can collectively call “psychical”, that is, feelings, emotions, moods etc. (love, hate, fear, anger etc.). These words are much less numerous (in the passage chosen there is not one of them).
3. Finally, there is a third class of words (or, in many languages, morphemes) that seem clearly different from the ones of the first two classes. In the passage chosen they are: the verbs “to be” and “to have”, the article “a”, the prepositions “upon”, “at”, “of”, “in”, “to”, the demonstrative adjectives “that” and “those”, the negations “no” and “not”, the conjunctions “and” and “but”, the numerals “once” and “one”, the adverb “there” and the morpheme “-s”, which indicates the plural. These words do not, or only minimally, seem to refer to anything physical or psychical. In the vocabulary of a language they are all the “grammatical” words, that is:

• prepositions (with, of, to, at, from, by, in, for, on, between, among etc.) and conjunctions (and, or, if, because, but etc.);
• interrogative-indefinite-relative pronouns or adjectives (who, what, which, whoever, whatever, whichever etc.);
• demonstrative adjectives and pronouns (this, that, other, the same etc.);
• main adverbs of place, time, manner etc. (here, there, where, when, how, why etc.);
• pronouns/adjectives of quantity (all, many, some, few etc.);
• negation (not, no, in- or un- as a prefix);
• numerals (one/first/once; two/second/twice; three/third etc.);
• fundamental verbs like “to be”, “to have”, “to get” etc.;
• most morphemes of the large number of languages that have a more or less rich morphology (the ones which indicate cases, in languages that have cases; the number of nouns and, in many languages, of adjectives; moods of the verb etc.).

In the passage chosen there are also two other words, “small” and “piece”, which, even if they are not properly considered “grammatical”, seem to be of the same kind (other examples can be: “big”, “high”, “low”, “beginning”, “end” etc.).

It is easy to realise that the number of items composing this class is quite limited (probably, they are more than the items of the second class, but surely much less than the ones of the first class), but, as a class, they are used in an extremely frequent way. If we choose samples of language at random, we will realise that this class is, in almost all cases, the main component of sentences and that it is absolutely indispensable in order to speak, that is, to make any speech up. Therefore, it is logical to consider it the fundamental structural component of language, and therefore of linguistic thought. We maintain that until we understand the nature of the meaning of these words, we shall not be able to understand the nature and the structure of linguistic thought.

Well, what do these words and morphemes indicate? In some cases, it may seem that these words, even if they do not indicate something physical or psychical, indicate relationships amongst physical things (in sentences such as “bottle of wine”, “he has a moustache” etc.) or features of physical things (in sentences such as “a large table”). Nevertheless, the same identical words may be used without problems in situations that have nothing to do with the physical world (for instance, we may say “stream of consciousness”, “to have an idea”, “a large number” etc.). Therefore, the answer to the question must be a different one.

Naturally, linguistics tried to give an answer to the aforesaid question [52, 53]. The solutions proposed so far seem unsatisfying. In order to realize this, it is sufficient to examine the definitions of these words that can be found in dictionaries. They use tautologies (for example, “not” is defined as “negation”) or false synonyms (for example, “to have” would mean “to possess, to own”, “to keep”, “to get, to obtain”, etc.) or they send us from one word to another word and then back (for example, the verb “to look for” is defined by means of the verb “to find” and vice versa). As far as prepositions are concerned, they are generally said to have a lot of meanings, that is, they would indicate many kinds of relationship (such as place, time, manner, cause, means or instrument, company or union, origin etc.). It is easy to object that it seems improbable that words, which occur so frequently and are so indispensable, have so many meanings. It is more likely that prepositions have only one, more general meaning (that is why it is so difficult to determine it), and that the many relationships grammar speaks about are only specifications, just introduced by grammar itself, which are included in this more general meaning: for example, it is more likely that the preposition “with” does not designate the relationship of company or union, manner, cause etc., but something more general in which the relationship of company or union, manner, cause etc. are included. In fact, several linguists themselves admit, more or less openly, that the definitions given of these words are unsatisfying [52, 53].

A completely new solution to this problem comes from OS. This kind of approach was developed, in the 50s-70s of last century, by S. Ceccato (1914-1997). Two of the authors of this paper, Benedetti [21-23, 38, 54-56] and Marchetti [20, 24, 25, 57-60], have deeply modified and developed it (because of this, they use a name that is different from the original ones ―such as Operational Linguistics and Operational Methodology― used by Ceccato). The fundamental thesis of OS is that these words designate sequences of mental operations (the name “Operational Semantics” derives from this), amongst which the ones of attention play a key role.

Ceccato called “mental categories” these sequences of mental operations, an expression that is also adopted by OS. We must notice the fact that this use of the expression “category” is completely different from the use made in Cognitive Psychology and Linguistics. Typically, Cognitive Psychology and Linguistics use the expression “category” to highlight the fact that, since many objects of the physical world share common features, but are not identical, we create classes by means of a mental process of abstraction [61-64]. On the contrary, OS calls “mental categories” the meanings of the words such as the ones we listed at point (3).

As we pointed out, according to OS, mental categories are made up of mental operations, which were called elemental mental operations by Ceccato. Also in this case, it must be highlighted that the use by OS of the expression “elemental mental operations” differs from the use made in cognitive sciences: while for the former it denotes only “elemental operations that make up mental categories”, for the latter it has a wider meaning, denoting also some other kind of operations that may be considered “elemental”, such as, for example, basic operations of perception. For this reason, in this paper we shall use, as much as possible, the more specific expression “elemental operations that make up mental categories”, or its acronym EOMC.

Below we shall try to summarise very briefly how, according to OS, mental categories are formed starting from EOMC and how linguistic thought is made up starting from mental categories, so that the reader can understand the experiments proposed in the last part of this paper.

Ceccato hypothesized that attention can only be in two states (attention waiting for something to be focused on, and attention focusing on something) and that the structure of the mental categories is made up of the various possible combinations of a progressively increasing number (2, 3, 4, etc.) of these two states. This hypothesis gave poor and controversial results in the analysis of mental categories. Nevertheless, Ceccato gave also some other sketched descriptions of the structure of several mental categories. Starting from these descriptions, Benedetti [22, 23] and Marchetti [20] have proposed a set of EOMC that is more complex than Ceccato’s, and have consequently put forward new analyses of the fundamental mental categories.

Benedetti and Marchetti’s proposals include both operations of attention and other kinds of operations, most of which have been repeatedly described in Cognitive Psychology. Starting from the seminal works by James [65] and Ribot [66], attention has been variously analysed and described: Posner [67, 68] and Posner and Cohen [69], for example, specifically describe the operation of orienting attention and the three elemental operations composing such an operation: engaging on a target, disengaging from it, and shifting to a new target; Jonides [70] describes the way attention can be focused at variable levels of size, being set either widely across a display of objects or narrowly to the size of a single object; La Berge [71] analyses how attention can be focused at variable levels of intensity; La Berge [72] describes how attention can be sustained or maintained for variable, though limited, amounts of time; Pashler [73] describes the different involvement of attention during the perceptual processing stage and more central, post-perceptual stages. The works by Braga-Illa [74-76] and Denis [77] describe in an extensive and quite exhaustive way the bulk of studies on representation in various scientific fields (psychology, sociology, logic, artificial intelligence, etc.). As to memory and its various forms and characteristics, see Baddeley [78], Baddeley and Hitch [79], Cowan [80, 81], Miller [82], Oberauer [83] and Oberauer et al. [84].

The new idea we propose is that by means of these operations we can account for the meaning of the words listed at point (3), hence for the nature and structure of linguistic thought. The list of the EOMC that Benedetti proposes is the following.

OPERATIONAL ARCHITECTONICS (OA)

As the details of the OA theory are beyond the scope of this paper, here we will only concentrate on some essential aspects which are important for the current discussion (primary references for OA theory are Fingelkurts and Fingelkurts [26-78, 30, 34-36]. In brief, the OA theory assumes that the level of organization at which cognition, phenomenal consciousness, and, in particular, reflective consciousness (in the form of linguistic thoughts) reside might be the highly organized macro-level electrophysiological phenomena (metastable operational modules) in the brain, which are realized by the coordinated electrical activity (operational synchrony) of many neuronal assemblies dispersed throughout the brain [26, 28]; for a similar view, see Revonsuo [91]. The activity of these neuronal assemblies is “hidden” in the complex nonstationary structure of the biopotential brain field – i.e., EEG (for the review, see Ref. [27, 34, 36]. At first glance the OA theory has some similarities with other important related theoretical frameworks, such as, for example, Dynamic Core [92], Resonant Cell Assembly [93], Global Workspace [94] theories, Framework for Consciousness [95] and Philosophy of Mind [96]. However, the OA theory has several crucial and important differences from all of them (for some argumentation, see Ref. [36]).

Let us briefly observe the main postulates of the OA framework:

1. One, and probably the most important one, of the different operations of the neuron is to process the electric currents which arrive on its dendrites and transmit the resulting electrical current to other connected neurons using its axon. This “blind” neurophysiological operation is, at the same time, the elemental physical operation of the brain (Table 1). Such operations have a fully neurophysiological ontology and they are completely NONconscious phenomena, which, according to Searle [97], have no mental/subjective ontology whatsoever.
   

   Table 1.

   		Description Within the Operational Architectonics Framework
   		single neuron	single neuronal assembly	single OM (several sinchronized neuronal assemblies)	…	complex OM (integrated several simple OMs)
   Brain levels	Physiological	elemental	complex	more complex	…	very complex
   	Cognitive	n.a.	elemental	complex	…	very complex
   	Higher-order reflective thought	n.a.	n.a.	elemental	…	very complex
   n.a. - Non applicable
   OM - Operational modules

   The single neurons (highly distributed along the cortex) can quickly become associated (or dis-associated) by synchronizing their operations and giving rise to transient neuronal assemblies. Here the emphasis is put not so much on the anatomical neural networks (as they are conceived in classical concepts [98], but rather on the functional interrelations of brain cells – transient neuronal assemblies [99]. Each of these functional assemblies represent/execute discrete elemental cognitive operations which process/present different attributes of objects, environmental scenes, or some other stimuli, including phenomenal objects of subjective experience [30, 35]. Thus, functional neuronal assemblies support discrete elemental brain operations, some of which may have already phenomenal/subjective ontology in addition to the neurophysiological one (Table 1).
   It has been shown that such neuronal assemblies have a transient dynamical existence (i.e. a functional life-span), which usually persists during short (millisecond) time intervals [100, 101]. These intervals represent the time needed for the neuronal assembly to execute/present a particular operation. It has been shown experimentally and in computational models that such intervals are characterized by fixed states of neuronal assemblies which are separated by rapid transitions [102]. Within the rapid transitional period the whole neuronal assembly can swiftly be rearranged [103].
   At the EEG level these operations of the neuronal assemblies are reflected in the periods of the EEG quasi-stationary activity within different frequency ranges, registered from different brain locations (for reviews, see Fingelkurts and Fingelkurts [26, 27, 36] and Kaplan et al. [104]).
2. The temporal synchronization of different brain operations executed by different local neuronal assemblies simultaneously (operational synchrony) gives rise to a new level of brain abstractness – metastable brain states [26-28]. These states are metastable because the neuronal assemblies which constitute them perform/have different operations/functions and each does its own inherent “job” (thus expressing the autonomous tendency), while still being, at the same time, temporarily entangled among each other (and thus expressing the coordinated activity) in order to execute a common complex operation or a complex cognitive act of a higher functional hierarchy [27]. As has been proposed by Kelso [105], metastability relates exactly to the phenomenon of a constant interplay between the autonomous and the interdependent tendency (see also Ref. [106]).
   Quantitatively such phenomenon is assessed through the measure of synchronization of EEG segments (structural synchrony) obtained from different brain locations [26]. These metastable brain states or functional Operational Modules (OM), as we name them, may underlie the realization of brain complex macrooperations (Table 1) – cognitive percepts, phenomenal objects, and reflective thoughts within the operational space-time continuum [30, 35].
   The key point here is that OMs have a more complex structure than the operations which constitute them. However, OMs carry less fine-grained information, since only the essential information for the emergent cognitive percept, phenomenal object, or reflective thought is preserved. For example, in the case of a visual perception, a large amount of information (intensity of the stimulus, lightness, colour, shape, size, proximity, texture and so on) is represented and processed by different neuronal assemblies, but at the higher level of abstractness (metastable OMs) the phenomenal image of an ‘airplane’, for instance, is presented. Thus, in accordance with the information theory of Shannon [107], the operational synchrony process ‘abstracts out’ the information carried by OMs, meaning that OMs are not sensitive to the original raw (neurophysiological) data anymore, but only to the spatial-temporal pattern of activation that is embodied in the involved neuronal assemblies. So, the information that remains is only an abstraction of certain aspects of the original data, including physical (non-mental) processes in the brain.
   The sequence of these metastable OMs thus may represent the stream of consciousness (for details see the second part of Fingelkurts and Fingelkurts [26]). The main idea is that the structure of the electrical brain field (EEG), the structure of cognition, and the phenomenal structure of consciousness, all have the same organization: the succession of discrete and relatively stable periods (metastable OMs, cognitive acts, or thoughts, correspondingly) separated by rapid transitive processes (abrupt changes between OMs, cognitive acts or thoughts, correspondingly)[30].
3. OMs (being by themselves the result of synchronized operations going on in distributed and local brain structures) could be operationally synchronized between each other (on a new time scale), thus forming more abstract and more complex OM which constitute new and more integrated phenomenal experience (Table 1; see Ref. [28, 36]. We argue that each of the new OMs is not just a sum of simpler OMs. Rather, the more complex OM is most naturally a union of abstractions about simpler OMs. Complexity hierarchy enables the brain to build complex phenomenal patterns/objects from primitive ones so that the semantic value of the complex representation is determined by, and dependent on, the semantic values of the primitives [28]. Such interpretation is consistent with some ideas established already by the early philosopher Thomas Aquinas (reprint [108]), who concluded that single events in the material world are not knowable, and that knowledge comes only through abstraction and generalization from the “phantasmata” of raw sensory impacts.
   In the end, such a process may lead to the generation of the most complex mental state, whereby visual, auditory, perceptual, bodily, emotional, cognitive, and other subjective experiences are unified. This state may well correspond to the personal “self” or even to a broader unified experience such as that of “subject” (for the distinction between self and subject, see Ref. [1]). Since also at this top level of abstractness (reflective consciousness) we do not yet have direct access to the brain processes, this subjective (conscious) experience seems so strange and mysterious to us [30].
4. Also the reverse process is possible – when a complex phenomenal pattern, object, or reflective thought (represented in the brain by complex OM) guided by attention is decomposed into several simpler phenomenal parts (OMs), which in their turn may be further decomposed into even simpler ones [27, 28]. The price for this decomposition is a narrowly focused attention and consequently the focused reflective conscious state [1].

CORRESPONDENCE BETWEEN OS AND OA

It is a fact that human language production and its phenomenal self-presentation are caused by neuronal activity and any speech signal necessarily activates neurons in the brains of listeners when being perceived [6]. Therefore, there should be a link between the structure ofthe electromagnetic brain field (EEG/MEG) and the structure ofthe higher-order reflective (linguistic) thought, whereby both of them, although seemingly worlds apart, must be intimately connected and mirrored in each other. However, owing to the enormous complexity of language and the brain functional structures, the subject of the putative correspondence between linguistic mental and neurophysiological brain levels has not been yet addressed directly.

At the same time, developments of recent years in the understanding of psycholinguistic [7, 20-23, 47, 54-56, 59, 60, 109, 110] and brain [6, 26, 27, 31, 36, 101, 104, 106] functioning have enabled researchers to identify and eventually to start experimentally to study the parallels between linguistic and brain levels within the same theoretical and methodological framework. To do so, the explanation should be made within the terms of a phenomenon that is shared by both organizational levels of the brain (phenomenological/mental and neurophysiological/biological) [30, 37].

We believe that the concept of “operation” is the required shared fundamental reference which provides us with a starting point for the conceptual integration and a unified research program. Both, the material neurophysiological organization that characterizes the brain and the informational order that characterizes the mind necessarily involve such events as operations at their cores. Generally, operation is broadly defined as the state of being in effect (for further discussion, see Ref. [27, 28]. It should be stressed that this is so regardless of whether this process is conceptual/phenomenal or physical/biological. In fact, everything which can be represented by a process is an operation. Understanding of the operation as a process and considering its combinatorial nature, seems especially well suited for describing and studying the mechanisms of how information about the objective physical entities of the external world can be integrated, and how unified/coherent phenomenal objects or thoughts can be presented in the internal subjective world by means of entities of distributed neuronal brain assemblies. It is only at this level of integration (through functional isomorphism principle) [26, 34, 37] that we may hope to relate and bridge the gap between linguistic level on the one hand and empirical evidence of its brain implementation on the other [30].

Up to date there are only two theoretical frameworks that explicitly aim to describe, measure and model the mind (OS theory) and brain (OA theory) operations involved in the complex human higher-order reflective consciousness (thoughts) which is governed by the brain.

According to OS theory, reflective/linguistic thought is always operational (made up of operations) and OS explicitly defines the structure of linguistic thought. This structure is characterized by correlators, correlata, and by a hierarchy of operations of increasing complexity. Likewise, in OA theory the brain functioning is also always operational (made up of operations) and the structureof the brain functioning is also characterized by a hierarchy of operations of increasing complexity and connections between these different operations. The basic idea is that the synchronized brain activity produced by local neuronal assemblies is linked to the required operation (or operational act) and only those local activities evoked by common objects, scenes, or tasks are bound together in dynamically formed metastable OMs [30, 36]. However, the whole level of OS description (elemental operations, categories, maps, and correlational networks) corresponds to the level of OMs (or set of them) of different complexity within the OA theory (see Table 1).

Below we shall propose some possible experiments which can shed light on the correspondence between the main postulates of OS and OA theories. The results of such experiments will either support the initial hypotheses and ideas, or not (and then the theoretical tenets should be modified). Altogether, this research program should give us a profoundly improved understanding of the complex linguistic thought processes, their putative modular architecture and their neurobiological implementation.

EXPERIMENTS AIMING TO TEST A PUTATIVE CORRESPONDENCE BETWEEN OS AND OA

As we have seen, according to OS, linguistic thought has two components: 1) representations or perceptions of physical and psychical things; 2) mental categories. Also the representations (or perceptions) of physical or psychical things can be products of operations. For example, the perception of a visual object seems to need the integration of features such as form, colour, movement etc., which are processed in a parallel way in distinct brain regions. The OMs identified by OA could be either the expression of binding operations of this kind, or of other kinds of operations. Nevertheless, OMs (or some of them) could be the expression of higher-level operations, such as the basic operations of linguistic thought theorized by OS. In this section, we shall try to outline some experiments that could reveal the putative correspondences between OS and OA.

As we have seen, OS hypothesises the existence of three operational levels in linguistic thought, which can be related to OMs of different complexity in the OA framework:

1. the level of the basic or elemental mental operations (EOMC) of linguistic thought, which could correspond to the simple OMs;
2. the level of mental categories, which are made up of EOMC. In some cases, we have hypothesised that we do not apply the EOMC to objects, but to spatial and temporal “maps”, that is, our mental representations of space and time, respectively, so that we could also look for something that corresponds to these “maps” or to their activation. This level could correspond to the complex OMs;
3. the level of correlational network (correlata tied by particular mental categories, correlators). This level could correspond to the consequent set of complex and simple OMs (that is, the “very complex OMs” of Table 1).

Therefore, we can look for correspondences between OS and OA at these three operational levels. Let’s consider them separately, taking the set of EOMC proposed by Benedetti and Ceccato’s correlational model as a first starting point for the search of possible correspondences between OS and OA.

CONCLUSIONS

Modern neuroscience can no longer ignore the mind phenomenon and is progressively starting to address the mind-brain problem seriously. This paper offers one way of dealing with this problem. We propose a plausible framework, which is based on the notion of operation and unifies within the same conceptual tissue mind Operational Semantics [20, 23, 38] and brain Operational Architectonics [26-28, 34-36]. We also provide a set of first experiments aiming to verify the putative correspondence we put forward between the OMs and what we consider to be the basic structure of a linguistic thought. As such, they can be further modified and developed.

Summarizing: The first step would be that of identifying the right level of correspondence between the (simple or complex) OMs discovered by OA and the EOMC, mental categories and correlational networks hypothesized by OS. Even if some first indications seem to show that some OMs are equivalent to basic mental operations (for instance, “keeping in mind” = “presence keeping”; “retrieval” = “representation”), additional tests are needed to support the hypothesis: they will show whether the same OMs configurations (be it, for example, that of “keeping in mind”) are present in different conditions where OS supposes they should be present (for example, when one uses the word “and” or the correlation adjective-noun) or not.

Ultimately, this research can be seen as a part of the larger research project concerning the neural correlates and/or neural constituents of phenomenal consciousness, where the term “phenomenal” refers to the undeniable facts (phenomena) of immediate subjective experience (including higher-order reflective forms) that occur to us (for a complete discussion, see Revonsuo [1, 30, 36].

REFERENCES