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The review of Prognosis.

Antedating responses are characteristic of organisms already at the lowest stages of the evolutionary range. The most perfect and complex forms of prognosis have been achieved by higher vertebrata. Such reactions enable survival, adaptation to changing conditions and the organism’s activity. The application of the probabilistic approach in neurophysiology is determined, primarily, by the multidimensionality of the Central Nervous System structure, the complexity and plasticity of connections within the organism, the fluctuation of the main parameters of physiological systems.

In real life people normally do not encounter isolated events. The accumulation of probability connections between particular events provides past experience, recorded in the memory. This involves the formation in the brain of functional temporary connections between activated excitation foci, which serve as the material substrate for the reflection of the probability characteristics of the environment’s alternative states. The stability of temporary connections depends not only on the probability of the event, but on its biological significance for an individual as well. As the amount of connections increases, sensitivity and readiness to perceive structured events rise significantly, for instance, in the form of signal sequences interrelated in a certain way.

It is of interest to remark the presence of a probability prognosis threshold ensuring the economical functioning of the brain. By executing prospective preadjustment to actions in a predicted situation, the organism identifies and “notices” only those few situations which are predicted with a probability higher than a certain initial value, which is the threshold of a probability prognosis. Prospective adaptation in accordance with the probability structure of a subject’s past experience may as well be executed at the subconscious level, that is, it is not always controlled and directed by consciousness. The value of the “threshold of probability prognosis” may be measured by analyzing the reaction duration, this providing the opportunity to assess quantitatively the extent of probability prognosis disarrangement.

It is known that the frequency of event occurrence determines to a significant degree the speed and accuracy of their perception. Therefore, the probability principle of the spacio-temporal organization of stimulus rows should be taken into consideration while studying the psychophysiological mechanisms of sensorimotor information reading, processing and reproduction.

Research has shown that the phasic process fades away more quickly if the expectation corresponds to the information presented. Thus, a slow extinction of the phasic process occurs in response to both signals which have not been encountered previously and those which do not correspond to the prognosis. Apart from that, signals possessing high informational and emotional significance also slow down the extinction of the phasic process. In addition, it should be noted that the presence of recurrent phases in the system of connections between the same neural populations is considered to be the condition of the functioning of short-term memory. In psychophysiology, reverberation of impulse flows is regarded as a mechanism for trace imprinting.

As follows from the above-mentioned, information processing is ensured not so much by one-time specific reactions of certain neural populations, but by their repeated involvement in the phasic process, implemented in the system of thalamocortical and limbicoreticular connections and accounted for by the peculiarities of the vertical organization of the Central Nervous System. Such impulse reverberation in neural networks may form the basis of the rhythmic activity of the brain.

Thus, the principle of the phase nature of information processing allows us to understand the physiological mechanisms which form the basis for revealing the connection between successive events, as well as shaping, information recording and reading.

It is known that the body’s antedating response to a vast number of environmental phenomena is determined by the ability of the brain to predict the further course of events. That is why the problem of forming an adequate prognosis of events which enables a person’s survival, that is, their environmental safety, occupies a central place among the urgent problems of human safety. Duo to the hypothesis concerning “psychic mutations” is undoubtedly of interest, presuming the functioning of a special brain mechanism which unites the nervous traces of exterior influences before the interconnection of these influences is revealed through rational cognition. Such antedating “psychic mutations” are later on compared with the reality. As a result of such a comparison, “mutations” which correspond to really existing interconnections between objects are fixed, i.e. the “secondary reflection” of the surrounding world occurs. At the same time, “psychic mutations” are not are not generated chaotically: out of a multitude of nervous trace combinations, only those which may perform the function of “secondary reflection” , i.e. execute the prognostic modeling of external object interconnection, are generated.

Human behavior has a very complex probabilistic character and thus ensures necessary orientation in the environment, its active creation and transformation. The peculiarity of human prediction of the environmental state is that in the vast majority of cases, people have to face probabilistic and random components of development processes which are revealed in the course of studying the object or phenomenon that is being predicted. That is why adequate prognostication stands for the ability of the human brain to create a subjective internal model of further events of the external world, relying on past experience and current information, in order to form reasonable and optimal behavior.

Prognostication is executed predominantly on the basis of biological and psychological regulation of human behavior. Various physical fields, both external and generated by the body itself (electric, magnetic, etc.) play an important role in biological regulation. It is known that the functioning of a living cell is unthinkable without electric activity, and every organ has its own specific electric oscillation. Thus, it is characteristic of a brain in a state of calm wakefulness to have rhythmical alpha waves with a frequency of 8-13 Hz, whose intensity changes in a state of sleep, during active wakefulness as well as under the influence of different stimuli.

The mental level of regulation is dominant in human behavior. It is on this level that the most adequate information exchange is performed; the opportunity to adapt to the environment and to create this very environment appears, this allowing us to define a special level of behavior regulation – the informational level. Memory impairments, which may manifest themselves as difficulties in imprinting and retrieving incoming information, play an important role in defining the mental form of human behavioral aspect regulation.

Different neurophysiological mechanisms of activity regulation may form the basis of such impairments.

In order to understand and explain the essence of phenomena observed in nature researchers often suggest general conceptual and concrete formal models as the most widely accepted imitation approach to analyzing the phenomenon under study.

It only became possible to reveal the patterns of reasonable human behavior regulation through the use of thoroughly checked complex approaches to analyzing types of prognostic activity and individual human differences which allow us to give a more definite integral assessment to the adequacy of human behavior.

The dynamics of the formation of human adaptive behavior in a probabilistic environment (that is, precautionary adaptation to expected changes) forms the basis of processes such as anticipation, set, prospective adaptation and probability prediction.

Relying on information concerning the present situation, provided by sense organs, and using arranged information concerning the past (memory) in a certain way, humans are capable of modeling the future only with a certain accuracy degree. Reacting in accordance with such probability prediction allows decreasing significantly the number of erroneous actions, that is, it is most beneficial from the point of view of an individual’s survival and adaptation to the environment.

In attitude psychology studies, the existence of different readiness to reacting to events, depending on the antedating parameters of a situation, has been revealed.

The results of numerous studies testify to a significant influence of the motivational-emotional sphere on the character of probability prediction activity. According to one of the hypotheses, human behavior in such cases is determined not only by the reinforcement character, but also the probability with which a subject expects the conservation of the same reinforcement system in future. Thus, the reinforcement itself (success/failure) proves effective only in the case when a person has the possibility to anticipate the results of their activity.

There is lots of evidence revealing directly the influence of the emotional state on the strategy of prognostic activity in probability situations: the decrease of emotional tension frequently leads to the strategy of probability indifference, while its increase leads to the predominance of the maximization strategy.

The formation of prospective adaptation for each kind of activity (or the level of information processing) determines a particular optimal diapason of emotional states or level of emotional tension, it being known that the transition to a higher level of information processing involves the contraction of the boundaries of such an emotional optimum. The level of emotional tension is judged upon by the intensity and breadth of involvement of a complex of different psychophysiological functions in the processes of organism mobilization.

When assessing the adequacy of this or that level of emotional tension for a given level of information processing, account should be taken, undoubtedly, of the effectiveness of the analysis (the intensity of entropy reduction in brain systems of information processing) as well as its psychophysiological “value”. The most adequate emotional state is characterized by “economical” psychophysiological expenditure of the functional structure in order to attain a high level of information processing.

Physiological shifts in the situation of such an emotional state may act as a means of enhancing the effectiveness of higher nervous activity self-regulation. A consequence of the activation of compensatory mechanisms in self-regulation processes, they can prevent the overstrain of information processing systems to a certain degree, as well as provide for them an optimal in terms of scale and structure return influx of effectors impulsation which tonicizes the brain. An emotional state characterized by “uneconomical” psychophysiological expenditure, even if it allows attaining a high level of information processing, should be considered inadequate.

An inadequate emotional state, by causing the hypermobilization of the CNS and the organism as a whole, leads to the derangement of the mechanisms of brain self-regulation and the decrease of the information processing level due to the exhaustion of energy and functional resources. As a result of continuous emotional tension, a general inadequate psychophysiological reaction of the organism characterized by the desire to avoid solving a problem situation may develop.

Three types of signal sequences – Bernoulli, Markov and unambiguously determined ones – were used in order to consider the influence of the correlation between probabilities of events and their order on the advancement of this or that prognosis. Three levels of prediction have been revealed: the lower level - event comprehension at the level of alternative recognition; the medium level – random prediction relying on immediate past events; the higher level – relying on a sequence of events (the conscious level).

However, the correlation of the frequency spectrum of prognoses with the real probability ratio of signals does not provide a complete notion concerning the organization of probability-prognostic activity, as there is a number of equally important parameters (such as decision-making strategies) which are not taken into account in this case. By the present time, numerous findings have been accumulated concerning the role of the qualitative component of human behavior in a probabilistic environment: the “rationality” of strategies enabling more precise prediction.

Many authors assume that strategies are determined by individual peculiarities of psychic self-regulation. That is why in many works, a more detailed analysis of testees’ actions in situations of probability choice is carried out.

Prediction understating the frequency of occurrence is observed during the prediction of the second most probable signal in a sequence. The best match between the predicted frequencies and real signal probabilities is observed in the case of choosing out of two alternatives equally significant for the tested. Passing on to choosing out of three or more alternatives is often accompanied by prediction overstating the frequency of the most probable signal. The trend towards maximization is particularly strongly expressed if the probability of one alternative exceeds significantly the probabilities of the others. In this case testees, having recognized the strategy of behavior optimal in this case, begin to achieve the greatest number of successful prognoses.

It has been proven that testees, executing probability prediction in the case of two alternatives may predict the emergence of one of the signals not only after a number of its successful prognoses, but also after a number of unsuccessful ones. However, as the choice task is complicated, for instance, by the reduction of the differences between the probabilities of the alternatives, the frequency of signal prediction increases after its reinforcement and decreases after its non-reinforcement, that is, a tested begins applying the tactics of “linear automation”. It has been revealed that the duration of the choice reaction represents a linear function of the average information quantity per signal.

It has been ascertained that the duration of choice reactions may increase as a linear function of the unexpectedness degree of the emergence of the signal.

An individual’s behavior strategy in a probabilistic environment is determined by a number of factors reflecting individual peculiarities of psychic self-regulation. There are several factors, such as: the factor of “sensitivity to the probabilistic environment”, testifying to human’s stable ability to perceive a certain level of connection between more or less probable events; the factor of “self-regulation plasticity”, reflecting a subject’s proneness to tactics diversity during the advancement of prognoses; as well as two factors of activity, reflecting the speed of psychic processes during prediction and its variability during the advancement of particular prognoses.

The presence of a dependence of prediction effectiveness on the rationality of behavior strategies applied by a tested has also been revealed.

Readiness to the prediction (or anticipation) of a certain event, undoubtedly, is reflected in the time of prognosis advancement in ratio to the emergence of the event: the higher the confidence in the occurrence of the event, the less time is spent on the act of its prediction. The transition from a simple reaction to an alternative choice is accompanied by increased dynamism of the period between the appearance of the electromyogram (EMG) and the start of motion. This period is connected with the functioning of the “action result acceptor” apparatus. The period of motion it is connected with the realization of a program of actions. However, progressive growth of response time ceases if the number of alternatives exceeds seven, despite further increase of situation uncertainty. Apparently, the number seven is a limit after which active prognostic activity ends due to a limited capacity for perception, memory and attention.

In this connection it is of interest to mention the presence of a threshold of probability prediction. This threshold serves the purpose of simplifying the present situation (as there is an unlimited number of alternative choices in a great deal of cases), thus providing economical functioning of the brain. Therefore, by performing prospective adaptation to actions in a predicted situation, the organism identifies and “notices” only those few situations that are predicted with a probability higher than a certain initial value, which is the threshold of a probability prognosis.

Prospective adaptation in conformity with the probability structure of a subject’s past experience may as well be carried out on the subconscious level, that is, it is not always controlled and directed by consciousness. The value of the “threshold of a probability prognosis” may be measured through a study of reaction duration, this providing the opportunity to assess quantitatively the degree of probability prognosis disorder.

A detailed analysis of probability-prognostic activity shows convincingly that human beings are characterized by a constant search for missing behavior strategies enabling more accurate prediction in a probabilistic environment. While trying to predict the emergence of another event, an individual behaves as if they consider the sequence presented to them to be not random but conforming to a certain law. Such behavior is observed even in the case of awareness of the probabilistic character of events, that is, an individual makes their prognoses as if they deal with a sequence depending on the results of their prognostic activity.

For a most comprehensive description of probability-prognostic activity, it is not only the facts of event prediction that are important, but also the degree of certitude with which these predictions are carried out. Subjective confidence in the correctness of choosing this or that alternative may be assessed by the strength of motor reactions during prognosis advancement, by the changes in the bioelectric activity of the brain during prognosis advancement and anticipation of alternative event realization. Through the use of testees’ self-scores of their confidence in their choices; it has been proven experimentally that the degree of certitude is connected with the relative frequency of successful prognoses in a certain way. There are also interesting findings concerning an individual’s attitude to their choice: testees, having chosen one of several alternatives, often change their rating of the situation in order to confirm the correctness of the choice that they have made, which is expressed in the subjective overstating of the probability for the chosen alternative and the understating of the probability for the rejected one.

It is known, that four factors of the structure of the prediction capacity have been singled out. The first factor involves such thinking qualities as analyticity, profoundness, consciousness; the second involves the flexibility of thinking; the third involves the prospects of thought and the fourth – convincingness of thinking. The set of these qualities, as well as the character of their correlation, is specific to this particular cognitive prognostic capacity. The first and second factors constitute the general and fundamental qualities of thinking; the third and fourth factors determine the qualities of thinking processes which are more specific to prediction, as it is through them that the probability character and temporal prospect of the future are taken into account.

Studying the process of probability prediction acquires particular urgency, as it determines the functional structure of activity regulation in the sphere of both psychic and energy processes. Prospective adaptation of the psychophysiological systems of the organism is formed in accordance with expected changes of the reality.

In the form of energy processes, the functional structure of the organism’s psychophysiological systems activity regulation is provided by the level of EEG activation: the criteria of the electrocortical components of the orientation response (the arousal reaction), characteristics of EEG coherence (CoH), criteria of the evoked potential component – the P300 wave and their asymmetry in the conditions of indirect and direct attention. In the sphere of psychological processes, the above-mentioned structure is determined by the effectiveness of prognosis formation. Prognostic activity and the dynamics of emotional states cause the changing of different frequency spectra of EEG activity. Thus, an increase in the total delta rhythm during the anticipation of probable pain stimulation and the increase in theta and beta rhythms under intense mental load with tight time constraints is observed. EEG registration straight in the period of probability prediction of signals revealed that signal anticipation is connected to alpha rhythm desynchronization, while the total energy of the EEG signal in the frequency band of 2 – 19.2 Hz reflects the degree of subjective signal anticipation, though it does not correlate with the duration of the reaction to it. A functionally significant increase in the synchronization level of cortical biopotentials in most cases is connected to the increase in the theta-rhythm, playing an important role in conduction of excitement processes.

The increase in the coherence and phase synchronism of biopotentials in the theta range is observed at the initial stages of formation of condition reflex, which we can regard as a particular case of probability learning with a reinforcement probability equaling 1.0. Further formation of condition reflex is related to the increase of this coherence (in inter-signal intervals), replaced by its weakening. After the generation of a temporary connection, coherence only appears during the implementation of a conditioned response. The increase in the level of spatial synchronization of cortical biopotentials may be accounted for by the increase in the coherence of the theta rhythm, generated in the neocortex. Thus, in principle, may be provided by the activation of uniquely intracortical mechanisms. This is confirmed by the experiment: a conditioned reaction is as well produced after the destruction or removal of the hippocampus or other structures of the archicortex.

Interhemispheric asymmetry of the human brain is the object of numerous electrophysiological studies. It is known that there is a significant difference between hemispheric specialization and hemispheric activation.

Hemispheric specialization stands for the readiness of a hemisphere for processing information of a particular type (verbal or spatial), or analyzing information in a special form. In this respect, the posterior portions of the left hemisphere may be specialized in analyzing information in a series, while respective portions of the right hemisphere may be specialized in parallel analysis. It should be noted, however, that values of hemispheric specialization as serial-parallel ones are applied to specific portions within the hemispheres and not to the hemisphere as a whole. Asymmetries in behavioral decision during the study of dichotic listening and divided visual field may reflect the differences between hemispheres in their ability to perform processes necessary for successful task accomplishment. Such specialization differences between hemispheres are often not absolute. Tasks, for which one hemisphere is more specialized, may also be solved by the other hemisphere, though in a less perfect way.

Specialization differences between hemispheres may be expressed differently. For example, a hemisphere may differ in terms of speed of problem solving. During the identification of words in a divided visual field, the left hemisphere (right visual field) responds quicker than the right one, without any precision difference between the visual fields. In the case of studying normal people, the difference in response speed is not a function of the difference in the speed with which each hemisphere solves the problem, but the speed of interhemispheric transmission. According to this belief, only one hemisphere takes part in problem solving in a response to a stimulus coming from one out of two visual fields. The reason for the presence of such a time difference is the duration of the transverse (transfer) of information from the hemisphere which has received it to the hemisphere “ready” to analyze such information.

Apparently, changes in both the mechanisms of functional specialization of the hemispheres and those of interhemispheric interaction, which form the basis for brain function integration, account for complex cognitive activity disorders, observed in persons with prognosis difficulties (DP). Differences in the functioning character of the systems of the left and right hemispheres during the perception process in two groups of testees probably reflect the peculiarities of the neurophysiological mechanisms of insufficiency. One hemisphere may be less capable of solving a certain problem type, as compared with the other. It is easier to interpret such differences as the manifestation of hemispheric specialization rather than reaction by time. For instance, the left hemisphere may be specialized in a linguistic analysis in a particular individuality, though this hemisphere may not necessarily be the most active during this kind of analysis.

At the same time, asymmetry in terms of activation stands for the level at which a hemisphere works or is adjusted. A hemisphere specialized in processing a certain stimulus is not necessarily the most active during the analysis of that stimulus.

EEG evidence of functional interhemispheric asymmetry both in a state of quiescence and during psychic activity is being studied.

Thus, the prevalence of the alpha rhythm amplitude has been revealed in one of the hemispheres of the brain, which is considered to be less activated than the hemisphere in which the alpha rhythm amplitude is lower. However, higher activation of one of the hemispheres in a state of calm wakefulness does not yet provide the grounds to assume that it is the hemisphere that plays a key role in the behavior of a given individual. The possibility of sign inversion of hemispheric activation asymmetry indicates its transient, functional character.

It has been revealed that under intellectual load the pronouncedness of the alpha rhythm in terms of amplitude and index is lower in the left hemisphere than in the right one. Right-side dominance of alpha depression has been detected during the performance of representational activities, while left-side dominance was revealed during the performance of verbal activities. Left-side asymmetry of the activation reaction in temporal, parietal and occipital areas of the cortex has been revealed while testees were doing mental arithmetic tasks. Beta rhythm changes have also been revealed under intellectual activity. The dependence of its manifestation on task quality has been remarked: right-side prevalence of the beta rhythm was observed during spatial task solving and left-side – during analytical problem solving.

It has been noted that at the transition from non-verbal tasks to verbal ones, either the decrease in the right-hemisphere dominance of the activation reaction or the replacement of right-hemisphere dominance by the left-hemisphere one occurs. Interhemispheric asymmetry is most clearly observed in central cortex areas during verbal (flash counting, anagram reading and solving) and representational (labyrinth tasks, Raven tasks) problem solving. In occipital cortex areas, the dominance of right-side EEG activation was remarked during all the representational tasks, with left-side activation dominance only being observed during anagram solving. These findings testify to a special sensitivity of the alpha rhythm indicator of the central brain areas to the correlation of representational and verbal components in testees’ cognitive activity. At the same time, they confirm the proposition concerning significantly higher generalization of right-hemisphere dominance of alpha activation during representational thinking, as compared with left-hemisphere dominance during verbal thinking, this conforming to neurologists’ views concerning lower differentiation of right hemisphere structures in relation to most psychic processes, as opposed to analogous structures of the left hemisphere.

It has been observed that mental arithmetic in persons with the right asymmetry profile was accompanied by changes in alpha-band parameters, testifying to the activation of the left hemisphere. Figure memorizing by these testees was accompanied by significant shifts in the frontal-temporal-central areas, manifesting themselves in the increase in the spectral power of beta activity and the increase in the alpha-range average frequency in right hemisphere leads, which indicates to its activation.

As it is known, humans have two interconnected forms of reality reflection, capable of transition into each other: the conceptual and the figurative one. Types of cortical activational structure with frontal-left and frontal-right localization of activation foci reflect different psychic content of the image: perceived either on the basis of verbal or non-verbal coding.

This correlates with the assumption concerning a different code for the hemispheres’ work. A successive code (the consecutive principle of information processing) is characteristic of the left hemisphere of human and animals, whereas the right hemisphere works on the basis of a simultaneous (parallel) spatial code. The left hemisphere is more closely related to the speech and sign basis of abstract-symbolic activity, whereas the right hemisphere is characterized by synthetic forms of thinking on the basis of spatio-temporal relations. It is known that the successive code is characteristic to left-frontal programming zones, while the simultaneous one is inherent in the right posterior gnostic cortex areas.

Thus, stable localization of the activation focus in the left frontal areas of the cortex during verbal-logical problem solving has been detected. In the case of representational problem solving, activation prevails in the right hemisphere and the activation focus shifts gradually from the frontal cortex areas towards the posterior ones.

Antedating responses are characteristic of organisms already at the lowest stages of the evolutionary range. The most perfect and complex forms of prognosis have been achieved by higher vertebrata. Such reactions enable survival, adaptation to changing conditions and the organism’s activity. The application of the probabilistic approach in neurophysiology is determined, primarily, by the multidimensionality of the Central Nervous System structure, the complexity and plasticity of connections within the organism, the fluctuation of the main parameters of physiological systems.

The research of prognostic activity provides the opportunity to differentiate testees into different groups according to the prediction effectiveness criterion (1 - adequate prognosing, average prognosing, poor prognosing). The comparison of the specificity of forming an ineffective prognosis with the results of electrophysiological examination gives the opportunity to reveal several neurophysiological mechanisms of the integrative activity deficiency of the human brain.

Thus, the study of intellectual capabilities of people, such as the states of perception, attention, memory, and thought, is becoming more and more topical, especially in view of the growing significance of the role of brain cognitive properties in its various functional conditions and during organic disorders. One of the forms of brain cognitive processes that characterize the level of person’s intellectual capabilities is considered to be its ability to adequately predict the events in external environment and also the choice of rational behavioral strategy.

The phenomenon of probability prediction and its individual peculiarities in humans are usually studied through the use of a commonly accepted method – the “guessing game”. This method consists in the following: the testees is offered to predict the appearance of the next signal out of two or more alternative options, presented in a random sequence with a preliminarily specified probability correlation in a certain way (for example, by pushing corresponding buttons).

For this purpose in experiment the computer variant of a psychological original method of Prognosis 1, 2 developed many years ago for adult healthy examinees was used. It provides immediate computer processing of the results of such testing based on a fundamental approach. The method based on human testing for the revealing of an interrelation order of two different symbols by its in three various sequences by a prediction of occurrence of this or that symbol. Sequences had different combination of symbols from two elements and a different order of its interrelation that defined level of complexity of sequence. In during of the experiment we offered a tested 3 sequences of symbols. These symbols were represented on cards placed faces down. The cards were arranged in a certain order unknown to tested. The tested had to reveal the order of symbols in sequences in each set (“A”, “B”, ♥ or ♠ ). The sequences contained different numbers of symbols. In the first sequence there were two symbols “AB”, the second one contained three symbols (ABB) and the third one consisted of five or seven symbols (BABBA or BABBAAB).

Now it follows the detail description of the program “Prognosis 2” working.