Subcortical Functions

SUBCORTICAL FUNCTIONS. The doctrine of the functions of subcortical formations, developed on the basis of anatomical-clinical (mainly), comparative anatomical, and experimental physiological research, has a history of many years and cannot be considered complete even in terms of defining basic concepts. The term "subcortex" is used in a collective, not always identical, and often conditional sense to denote a series of anatomical formations of the central nervous system, located in the anterior parts of the brain stem up to and including the forebrain, important for their physiological role. As synonyms for subcortex, "basal ganglia", "central", "subcortical ganglia", "stem ganglia" (Stamm-ganglien), "extrapyramidal system", "striate system", and the French "corps opto-stries" are used, and the content of these terms does not always coincide. Thus, some authors exclude the thalamus from the concept of "basal ganglia" (synonym corpus striatum), relating to the basal ganglia the gray nuclei of striati, pallidi, corpus Luysi, substantia nigra, nucleus ruber, and corpus dentatum cerebelli, and Jacob combines the first four formations into the concept of the "main extrapyramidal system". In the concept of the "striate system", Foerster includes the medioventral nucleus of thalamus, tuber cinereum, and a number of small formations (nucleus of the posterior commissure of Darkshevich, interstitial nucleus); the connection of substantiae nigrae and nucleus rubri with this system is questioned by Foerster. Authors who approach the study of subcortical or basal ganglia anatomically or comparatively anatomically (phylogenesis, ontogenesis) do not invest these terms with such broad content, and for them the term basal or subcortical ganglia is not a synonym for the extrapyramidal system (see Basal ganglia). This discrepancy in the grouping of these formations finds its explanation in the diverse approaches to the study of subcortical functions, which essentially underlie the anatomical unions. From this point of view, the concept of subcortex is not a purely anatomical concept, but rather physiological-anatomical, and most broadly encompasses the functions of the entire conglomerate of the named formations—their role in motor activity, in psychical activity, and in the regulation of vegetative functions. As early as the end of the 19th century, Anton, relying on the opinions of Meynert, Nothnagel, and Gowers, gave an anatomical basis for choreatic and related movement disorders, reducing them to a lesion of one part of the extrapyramidal system—the motor path of the tegmentum. Together with Bonhoeffer, who expressed the hypothesis of the participation of the anterior cerebellar peduncles in chorea (1897-1901), he laid the foundation for all subsequent concepts of the functions and role of the extrapyramidal system. Subsequently, Monakow, and after him Niessl-Mayendorf, and more recently Stern, admitted changes in motor activity of the cortex under the influence of subcortical mechanisms. Among the works of Russian authors who studied the system of subcortical ganglia mainly from the anatomical side, the works of Minor (1882), V. A. Muratov, Bekhterev, and Grinstein (dissertation, 1910) should be noted. In 1907, Khorshko, in connection with a particular question about the pathogenesis of Kozhevnikov's epilepsy, raised the general question about the role of subcortical mechanisms in the development of phenomena of constant hyperkinesia. The further doctrine of the motor function of the subcortex is presented in the works of Jacob, Foerster, and Lewy. Along with the identification of motor functions of the subcortex, its role as the highest regulator of vegetative functions in the innervation of smooth muscles, blood vessels, sweating, thermoregulation, and regulation of metabolism was also clarified. Incidentally, in this connection, a close dependence between the vegetative nervous system and motor activity was established. The methodological prerequisites for the study of subcortical functions were mainly clinical data, as well as experimental-physiological data, the significance of which has especially increased in recent times. However, it should be pointed out here the lack of criticism noted in many authors who try without sufficient grounds to transfer data obtained on animals to the field of human pathology. Another important point in resolving the question of the activity of the subcortex is the predominant use of clinical, i.e., pathological, material; therefore, one must be extremely cautious not to make purely mechanical conclusions from pathological data regarding the normal role of the subcortex. The subcortex as an integral whole is a connecting link between the lower, phylogenetically most ancient stem mechanisms and the higher, neoencephalic parts of the nervous system. For the former, it serves as the highest unifying apparatus, completing a certain stage of phylogenetic development and being the highest locomotor organ (fish, reptiles, and birds); for the latter, it plays the role of an auxiliary, adaptive apparatus, which under these conditions receives new, to some extent qualitatively different functions in locomotion—not only kinetic but also adaptive statikotonic, which only appear in previous stages, and also setting functions for neoencephalic activities, which to a large extent participate in psychical activity, the affective sphere through the regulation of vegetative functions and psychomotorics in the broad sense. This reflects the general law of progressive displacement of functions in the process of phylo- and partly ontogenetic development ("progressive cerebration") in the direction of the cortex, significantly modifying the basic functions of the subcortex by the appearance of not only new connections with the cortex but also the structural complication of the subcortex itself and the complication of its functions. In the subcortex, two main departments are distinguished—receptor and effector. The first is represented, on the one hand, by the thalamus, which is the main center of sensitivity (entero-, proprio-, and exteroceptive) of the whole body, on the other hand—formations of hypothalami, receiving and sending to the effector part vegetative impulses. The effector part, representing the entire extrapyramidal system as a whole, combines in itself motor and vegetative functions. The kinetic and statikotonic role of the subcortex. Motor acts in higher animals and especially in man are a complex integral whole, synthesizing in themselves a number of components of different functional significance and different phylogenetic age. Considering movement in the process of ontogenesis and phylogenesis, one can somewhat arbitrarily distinguish in it archaeo-, paleo-, and neokinetic forms (Hunt). Archaeokinetic, the most ancient forms, are connected with the function of the oldest formations (spinal cord mechanisms) and in form are least complex, representing simple reflexes. With the function of subcortical ganglia are connected paleokinetic forms, which in general have an automatic character but are already much more complex than the previous ones and differ in the smoothness and rhythmical nature of movements. Neokinetic forms are a product of the cortex and therefore are the most developed, differentiated, and variable. With the development of neokinetic forms, the more ancient paleokinetic ones become subordinate to them. Thus, the extrapyramidal system, by means of the kinetic elements it introduces into movement, becomes the basis on which the entire complex, differentiated motor activity of the cortex unfolds. The kinetic function of the subcortex, in contrast to the cortical one, manifests itself in reactions that do not depend on our will and are revealed in orienting, expressive, and "instinctive" movements and in various automatisms with the character of synergistic and auxiliary movements. The entire sum of the listed reactions presupposes the presence of certain biologically ancient mechanisms. In relation to the cortex, part of these mechanisms (automatic movements, some synkinesias) plays a service role and they can be considered as praxias of a lower order, just as the spinal cord, storing the elements of the automatism of walking, concentrates in itself as it were elements of praxias of an even lower order, coordinated with the higher mechanisms. In the very characteristic of subcortical reactions, one should note their rhythmical nature and the ability to reciprocity (change of innervation and denervation), which ensure timely contraction and relaxation of muscles participating in movements. The rhythmical nature of activity, inherent in all parts of the nervous system, is very clearly expressed in the functions of subcortical mechanisms. The rhythmization of movement is connected with the distribution of its individual elements in time and space in such a way that a regular connection is formed between these elements. Movement thanks to this becomes uniform, orderly, sequential. The usual tempo of movement (i.e., motor production in a unit of time), determined besides its subcortical components also by the activity of the cortex (and therefore motor experience), as well as the biochemical peculiarities of the organism, characterizes the individual properties of motor activity.

The participation of the subcortex is highly probable not only in the regulation of primary, already mentioned above, automatons, but also in the formation of secondary automatons [automated movements that are habitual actions according to abbreviated formulas as a result of kinetic experience (Markelov)]. These acts are of a semi-reflex nature and differ from primary P. automatons to some degree by the participation of consciousness in them. Automated movements are predominantly a product of the frontal sections of the cortex, which are closely connected in the process of individual development with the activity of the subcortex. In an adult, they should be considered as a result of the activity of the frontal and extrapyramidal systems. On the example of this mechanism, one can see how the subcortex in humans acquires new qualitative features compared to the function of this formation (also sufficiently strongly developed) in primates, and it is on this that the correctness of the principle of multilayered and multi-system provision of the same function by different parts of the nervous system is confirmed. - The question of extrapyramidal tone is closely related to the statikotonic function of the subcortex. In tone, at least the following components are distinguished: primary muscle tone, spinal, subcortical, labyrinthine (closely connected with this is the influence on the tone of the cerebellum) and cortical tone. Such a division of tone is of course schematic, however, it still has to be used when studying the functions of individual formations. P. tone is characterized by plasticity (Hunt's statotonus), in contrast to the elastic cortical tone (see). The statikotonic functions of the subcortex, which at early stages of phylogenesis are one of the phases of movement, later at the height of motor development become as it were its 'background', revealing more and more clearly the adaptive functions of the subcortex. The complexity of the function of the subcortex is especially vividly manifested in its pathophysiology. The latter was largely revealed in the study of a number of syndromes and pathological forms, of which the main ones are: epidemic (lethargic) encephalitis, paralysis agitans and parkinsonism, Wilson's disease (hepatolenticular syndrome), Westphal-Strümpel pseudosclerosis, Sydenham's chorea, Huntington's chorea, torsion spasm, bilateral athetosis (athetose double). In recent times, some authors (there are also other views) have linked the pathophysiology of the subcortex with such syndromes as narcolepsy, cataplexy, and some forms of epilepsy. In connection with the identification of these forms, the doctrine of diencephaloses (functional insufficiency of diencephalic formations) arose, in which not only the role of the subcortex in motor function is taken into account, but also the regulation of vegetative functions, closely related to it in functional and anatomical aspects. - The study of these pathological forms leads to the distinction of a number of syndromes. The pallidal syndrome (with bilateral lesions of the pallidum) consists: 1) in severe rigidity of the muscles, apparently due to the disinhibition of subpallidal centers, which causes an increase in plastic tone, an increase in passive resistance of muscles to stretching (increase in postural reflexes), leading to adaptive and fixation contractures of the muscles, 2) in the presence of tremor in the resting position of the limb due to the destruction of the influence of the pallidum on the cerebellar systems, 3) in the weakening of reactive expressive movements or their inhibition, 4) in the poverty of voluntary movements and their slowness. All this determines the peculiar appearance and form of behavior of patients: absence of kinetic activity, poverty of motor initiative due to the weakness of support for voluntary impulses from the paleokinetic mechanisms of motor function. According to Förster, this syndrome is called hypokinetic-rigid. Recently, Kleist (Kleist) has attempted to classify the functions of the pallidum, distinguishing in it motor and miostatic functions and connecting them with its different parts. The striatal syndrome is much more complex and diverse than the pallidal one, since it reveals the pathology of more complex kinetic functions of the subcortex, connected with more differentiated organs of the striatum. This syndrome, just like the pallidal one, can be characterized: 1) by the poverty of orienting movements, protective and defensive reflexes, 2) by the loss of individual components of voluntary movements, which manifests itself in the impoverishment and slowness of the latter, 3) by some hypertonicity, but this striatal akinesia is not necessarily accompanied by rigidity, as is observed in the pallidal syndrome, and is an expression of the loss of higher paleokinetic innervation. However, striatal akinesia is less common in lesions of the striatum than striatal hyperkinesia (choreatic, athetotic syndromes and some of their subtypes). - The choreatic syndrome (see Chorea), associated mainly with lesions of the small cells of the striatum and disinhibition of the pallidum, is manifested mainly in the presence of involuntary, twitching movements, remotely resembling voluntary expressive and synergistic movements. Along with sharply expressed violations of purely kinetic functions, manifested in the form of hyperkinesia, in this syndrome there is also a violation of static functions, associated with a change in tone, which causes an inability to keep parts of the body in a fixed position. The plastic tone in this syndrome is reduced, the resistance to passive stretching of muscles is decreased, the extensibility of muscles is increased. - The athetotic syndrome (see Athetosis), also by most authors associated mainly with lesions of small and large cells of the striatum ('status marmoratus' of Foix), is manifested in peculiar hyperkinesias of a bizarre character, usually localized in the distal parts of the hands, sometimes extending to more extensive territories up to the development of the so-called athetose double (see Athetosis, athetose double). Voluntary movements in this syndrome are combined with irregularity in the innervation of the corresponding motor mechanisms and with the appearance of excessive synergistic movements of a mass character. However, hyperkinesia does not disappear in complete rest. In this syndrome, as in the choreatic one, a decrease in plastic tone and excessive extensibility of muscles is most often noted. The significance of the athetotic syndrome for understanding the function of the subcortex lies in the fact that in these athetotic movements one can see, although strongly distorted, an expression of the functions of the disinhibited pallidum with its phylogenetically old mechanisms. Torsion spasm (see) is closely related to the latter syndrome, the basis of which is apparently also partial disinhibition of the pallidum due to selective lesions of some parts of the striatum. Similarly, in this syndrome, a violation of static-tonic components (dystonia, extreme extensibility of muscles) and kinetic (anomalies of reactive, expressive movements, disinhibition of mass movements) is noted. Kleist also tries to give a somatotopic localization in relation to the striatum, connecting with the nucleus caudatus psychomotor, kinetic functions, and with the putamen - staticotonic functions. It should however be noted that the close connection of the pallidum and striatum leads to the fact that isolated violations of the functions of only one of these formations are usually not observed, and more often one has to deal with a mixed strio-pallidal syndrome. It is observed in the clinical picture of Wilson's disease, as well as in Westphal-Strümpel pseudosclerosis and some forms of epidemic encephalitis. The syndrome of Luys's body (see Hemiballismus, Corpus Luysi), consisting of a sweeping hyperkinesia of choreatic character with pronounced rotational and torsional components, gives some right to see in this formation (corpus Luysi) a special mechanism that developed in higher primates with a vertical body position (especially in humans) and connected with the function of rotation of the body around the vertical, caudo-oral axis. The function of the substantia nigra is clinically not sharply defined. With this formation, developed mainly in humans in connection with the orthostatic position and walking, a number of authors associate the regulation of tone and sequence of movements in gait. In lesions of this formation, the hypokinetic-hypertonic syndrome (Tretyakov-Shigrinsky theory of rigor) is particularly sharply revealed. - A much greater role in orthostatic and orthograde function, as shown mainly by experiments of the Magnus school, is played by the nucleus ruber. This formation, located at the junction of pathways coming from the cortex, cerebellum and various subcortical formations, plays a huge role in the regulation of the so-called anti-gravitational tone (tone of muscles whose action is directed against the force of gravity) and in the function of transition to a standing position. Lesion of this nucleus causes the main part of the Benedict syndrome, giving contralateral tremor and ataxia.

The appearance of a particularly characteristic broad tremor in certain diseases (pseudosclerosis) is also associated with damage to the red nucleus.-When considering subcortical motor function, it is necessary to point out the important role of the cerebellum, which directly participates in the regulation of reciprocal innervation and in regulating the direction of movements of the body and its parts. In addition, the cerebellum also regulates tone, participating in the static-tonic function of the subcortex. Gents recently, by analogy with the division of kinetic functions of motor function into paleo-, archeo- and neokinetic forms, also distinguishes in the functions of the cerebellum with respect to the static-tonic function the archeo-, paleo- and neostatic forms of these functions. Vegetative functions of the subcortex (see also Vegetative nervous system, Regio subthalamica and Sleep). The connection between motor function and the vegetative nervous system is most clearly demonstrated in the static-tonic function of the subcortex-in the regulation of muscle tone (see Tone). The vegetative nervous system (in particular the sympathetic), according to the works of Orbeli, has adaptive significance for striated muscle, maintaining at one level or another the excitability of the muscle with respect to impulses of a kinetic nature sent along the paths of the cerebrospinal nervous system. This close dependence of motor functions and tone is especially evident in the early stages of phylogenetic development, when both of these functions are performed by the same system. This should be compared with the close anatomical and functional union of the motor functions of the subcortex and its vegetative functions related to the regulation of tone (see Tone). Indeed, the subcortical ganglia are connected with hypothalamic formations and the gray tubercle, which regulate vegetative functions. A number of clinical and experimental observations allows the localization in the same formations of the regulation of both motor function and vegetative functions (striatum, corpus Luysi, substantia nigra Sommeringi), and a number of authors (Dresel, Lewy) consider the striatum also as an organ of higher regulation of vegetative functions. On the other hand, impulses also go from the subthalamic formations into the thalamus-striatum-pallidum system. This close interdependence of motor and vegetative functions of the subcortex is very important for the state of muscle tone. Another biologically important function of the subcortex, connected with a series of vegetative innervations, is the regulation of wakefulness and sleep. Data obtained mainly from the study of epidemic encephalitis have forced recognition of the existence in the subcortex of important parts of the mechanism of wakefulness and sleep. Disturbance of the functions of these mechanisms leads to various disorders of sleep and wakefulness, and possibly results in the appearance of narcoleptic and other similar conditions and pr. Functions of the optic thalamus-- cm. Thalamus Opticus. L. Nemlicher, V. Chernikov. 81

SUBCORTICAL FUNCTIONS Subcortex and mental functions. Some, especially Western European, authors speak of mental functions of the subcortex. Such a crude localizationist view, of which the mechanistic and at the same time vitalistic hypothesis of Haskovec about the 'subcortical soul' can serve as an example, completely does not correspond to the now undeniable position on the integrity of the psyche and the complexity of the relationships between it and the central nervous system. It is more correct to speak of the role of the subcortex in mental functions, and its activity cannot be thought of outside the connection with the activity of the cerebral cortex. A huge literature has grown to clarify this question, which has developed mainly in the last 15 years. The direction that seeks to consider the structure and functions of the nervous system from a phylogenetic perspective has strongly influenced its formulation: a series of studies is based on the recognition of the indisputable position that at certain stages of phylogenesis, one can establish the direct participation of the subcortex in higher nervous activity. Proceeding from this, various authors (Camus, Naville, Lhermitte, Logre, etc.) built hypotheses about the 'ascending' influence of the subcortex on the psyche. Among the most important functional properties of the P. ganglia, the greatest significance is attached, on the one hand, to the motor function, and on the other hand, to a complex of central vegetative functions to a large extent associated with the affective sphere; the first reflects the role of animal integrative processes in the synthesis of personality, the second reflects the role of vegetative, neurohumoral processes. K. Kraus speaks a lot about the P. basis of the so-called vegetative life in connection with the construction of personality in 'Biology of Personality'. The character of Kraus's teaching is determined by the term he proposed 'deep personality' ('Tiefenperson'). This term, as well as Kraus's teaching itself, is essentially connected with the idea of the significant autonomy of the 'deep'—subcortical-vegetative, endocrine, etc.—levels of personality, an idea that is essentially incorrect. The role of the animal nervous system, especially motor functions and mainly subcortical motor functions, in the life of personality has been examined by A. Geimanovich in his concept of 'neurology of personality'. According to this concept, subcortical motor function leaves its imprint on those motor mechanisms that, ultimately controlling movements, also participate in determining the motor character of personality. It would be a mistake to understand this category of subcortical 'neurology of personality' associated with motor function as something self-sufficient; here one must have in mind a complex of automated, preparatory, etc., movements that to a large extent characterize the individual peculiarities of different people and serve as a stable basis for the conscious motor function of man. Both of the indicated categories—motor-neurological and vegetative-humoral-neurological, as well as other categories of the subcortex—in the final analysis do not appear in isolation from each other. In the very concept of the so-called 'expressive movements', in the genesis of which the role of the subcortex (visual thalamus) is always emphasized, there is an assumption about the connection between the vegetative-affective and motor spheres in their dynamic manifestations. Similar connections—in their static reflection—can be testified to by other facts, for example, the frequent combination with asthenic constitution of angularity of movements in schizophrenics, whose motor function is determined by P. pathology or a violation of the correct ratio between the cortex and subcortex. The special question of the relationship between the cortex and subcortex in psychomotorics was elucidated by Bernadou. Studying tics, this author distinguished, among other types, centrifugal psychomotority ('the current of action is directed to the motor apparatus from mental centers') and centripetal psychomotority ('ascending impulses from motor centers of the nervous system to mental areas'). The latter type Bernadou called ascending psychomotority (an illustration of this position: in tics, one can observe various verbal stereotypes following various compulsive movements). However, it is hardly possible to fully accept such a simplified vertical in relation to the psyche. In more severe cases, the connection between subcortical-motor pathology and dissociative processes in the psyche is more obvious, for example in cataplectic rigidity, where Lange admits a blockade of the psyche originating from the subcortex. In the history of P. theories of mental life, Kleist played the largest role, creating the neurological direction in psychiatry and emphasizing the role of the subcortex in a number of psychopathological phenomena (obsessions, changes in character, delusional states, volitional disorders, etc.). The theoretical views of Kleist are the fruit of great and valuable work, but at the same time they are mechanistic, since they directly transfer complex neurophysiological acts in themselves to the sphere of interpretations of the mental picture. A serious impetus to the analysis of the motor P. function in connection with mental life was given mainly by the beginning of studying the amyostatic symptom complex in epidemic encephalitis. Here, in the state known under the name of parkinsonism (see) and connected with the lesion of the striopallidal system in epidemic encephalitis, the connection between motor rigidity and a specific mental picture could not fail to attract attention. This mental picture is successfully designated as 'bradyphrenia'. This state of the psyche is essentially different from the psychopathological pictures known until now: it is characterized by specific lethargy, based however not on the disappearance of affectivity (which can manifest itself in encephalitics) and not on an intellectual defect; rather it is a specific lack of initiative, in which the various phases of current life seem monotypic and there are no flashes of interest that could create new waves of desires and impulses—over all this dominates slowing down and monotony of tempos. Attempts to explain bradyphrenia only as a result of motor rigidity proved to be untenable for the following reasons: 1) other non-extrapyramidal forms of akinesia do not give states similar to bradyphrenia, and 2) individual cases of encephalitis without rigidity can also give a picture of bradyphrenia (parkinsonism without a motor component). In connection with this, the assumption was made of the existence in the striopallidal system of a 'specific activator' of motor activity, namely the concentration here of 'drives' ('Antrieb'), mainly motor ones. This assumption is very probable, one only has to keep in mind that here we are talking only about the subcortical component of the corresponding mental phenomenon, which as a whole, as a volitional drive, is determined by consciousness, and its relation to the subcortical component must be represented similarly to how the relation between the affective preparatory charge originating from the visual thalamus and the affect itself entering the complex of our conscious life is conceived. The complex question of how to understand the pathomechanism of 'insufficiency of drives' was resolved differently. Bostroem believed that in parkinsonians at this time, in connection with motor difficulties, there arises the need to replace movements, which in the norm are habitual and automated, with movements that are subjectively voluntary. In connection with this—there is a leveling of movements in general, regardless of their degree of significance—all of them become voluntary and each requires a separate volitional effort; this equalization of significance of motor acts leads to the absence of their affective accentuation—from here the smoothing out of drives and their insufficiency ('Mangel an Antrieb'), which according to Bostroem depends on the subcortical-central motor insufficiency. It goes without saying that in the presence of rigidity, the difficulty of performing coordinated movements as a whole also creates a reverse influence on mental life. Bostroem however assumes insufficiency also in the sphere of instinct, which is inseparably fused with affective life. Stern illustrates the possibility of the existence of subcortical components, 'drives' by the fact that in parkinsonians, pauses in actions and attacks of catalepsy sometimes arise, which cannot be explained only by motor difficulties and are obviously due to the weakness of the indicated subcortical components. Along with the specific for epidemic encephalitis P. mental adynamia in subcortical pathology, obsession (Zwang), 'dysfunction' of drives is also encountered. A typical example of this is the monotonous nagging of parkinsonians, manifested in the inflexibility of their psyche, in their lack of proper distractibility, and in their tendency to mental iteration, i.e., repetition of the same thoughts, verbal expressions, and actions. Subcortical iteration of actions and words can also be seen in other P. lesions—in cases of P. tumors, in Alzheimer's disease (see), etc. The dependence of psychomotorics on the subcortex is vividly demonstrated by the appearance in connection with P. pathology of such psychomotor phenomena as poriomania in epidemic encephalitis, mental excitement in chorea, which sometimes remains even after the smoothing out of hyperkinesia, etc.

According to Kleist, the specificity of psychomotor disorders lies in their close connection with psychic phenomena, namely that in psychomotor disorders there is formed, as it were, an ideational side that explains these motor phenomena. An example of this and at the same time a general principle of psychomotor pathology can be the data from Geymanovich's observations on subcortical lesions in epidemic encephalitis (1927). In one case, it was a matter of a 'prepsychic' motor setting: in encephalitic Wilsonism, a fairly prolonged, one-sided stretching spasm of the mouth was established, and this served as a trigger for laughter. In another case, there was a 'postpsychic' motor setting: in an encephalitis patient, after a conversation, a special spasm occurred - the lips were folded into a tube, the nostrils flared up, as if repeating 'readiness for speech'. Of particular interest in connection with the study of the subcortex is the schizophrenic-catatonic group. Catatonic-like pictures can be encountered in various cases of subcortical pathology, for example, in subcortical tumors, progressive paralysis, etc., but they are of particular interest in epidemic encephalitis. If at first parkinsonism was erroneously equated with the catatonic picture, it was later found that only certain forms of encephalitis actually approach the schizophrenic-catatonic syndrome. The difference between ordinary catatonia and the catatonic-like picture in an organic patient with subcortical damage is generally determined by the fact that although in catatonia there are occasionally settings similar to extrapyramidal ones, nevertheless a number of characteristic extrapyramidal symptoms are always absent, whereas catatonic-like syndromes in organic motor psychotic states differ from catatonia in the absence of specific schizophrenic-catatonic changes in the psyche. Geymanovich, as a working hypothesis, suggested (in 1923-24) that in catatonia one can think of a peculiar disorder of subcortical tonus from the cortex, whereas in epidemic encephalitis, for example, it is a matter of damage to the subcortex itself. Indeed, on the one hand, the cortex undoubtedly participates in the schizophrenic process, on the other hand, there is at least an external similarity between schizophrenic-catatonic settings and extrapyramidal ones, but in most cases a number of characteristic signs indicating damage to the subcortex proper is absent. Schilder somewhat hastily admits roughly the same interpretation with respect to certain neuroses, for example, hysteria. The difference from schizophrenia, according to Schilder, is that in neuroses it is a matter of a certain temporary dissociation, whereas in schizophrenia it is a constant process conditioned by the state of the organism itself (one can hardly be satisfied with such a quantitative difference in the interpretation of neurosis and schizophrenia). Schilder adds that damage to the striopallidal system alone cannot give either a hysteroid or a true schizophrenoid complex. - Delusional states in epidemic encephalitis, associated with subcortical lesions, were also explained differently. Thus, Quint believes that epidemic encephalitis can give a paranoid form of mental disorder as a result of affective dysfunctions (perverted sensations), difficulty in adapting to life's conflicts (due to the akinetic syndrome) and the resulting incorrect interpretations. Certain forms of hallucinosis (see) are also associated with the subcortex. These explanations are understandably only hypothetical. - Especially severe mental changes are left behind by epidemic encephalitis in children. Childhood epidemic encephalitis is mainly characterized by peculiar changes in character, amoral tendencies and sexual aggressiveness, in general the so-called 'anethic' symptom complex (Albrecht). This symptom complex, which sometimes occurs in adult parkinsonians, is explained in children by the onset of the disease during the growth period and thus by early disturbances of the complex interrelationships between the cortex and subcortex. In a certain connection with the role of the thalamus in mental processes stands the role of the hypothalami with its numerous forms of participation in the vegetative and cenesthetic life. Nemlicher and Sinegubko report an original case of sensation of enlargement of one's own body in hypothalamic lesions (a pathology that can also give rise to delusional ideas). - Certain pathological states of sleep also belong to subcortical pathology. These include narcolepsy (see), the state of stiffness in nightmares and the 'blockades' of tonus related to these forms - cataplexy with inhibition of the muscles intended for maintaining the body in a vertical position, or the state of catatonic immobility while performing a specific act; with these forms are also associated corresponding mental states. - Experimental-psychological studies in subcortical lesions (resp. in epidemic encephalitis) were conducted in various directions (Chuchmarev, Kirby and Davis, who established in parkinsonism a sufficient number of associative processes, etc.). Parkinsonism also gave rise to the study of conditioned reflexes (satisfactory condition of salivary reflexes according to Chuchmarev; Popov found extinction of motor conditioned reflexes). The subcortex is associated with the rather indefinite concept of instincts (see). With regard to them, I. P. Pavlov made an attempt to connect the activity of the subcortex with the work of the cerebral cortex. Pavlov translates both these forms of nervous activity into the categories of reflex activity and attributes to the subcortical nodes 'unconditional special most complex reflexes' (instincts) in contrast to conditioned reflexes associated with the cortex. In this, the subcortical nodes are characterized, in Pavlov's expression, by considerable rigidity. On the one hand, it is known that a dog without large hemispheres does not respond to the enormous mass of irritations falling on it from the external world, to which a normal animal constantly and vividly reacts. On the other hand, the already begun and continuing irritation is characterized by rigidity. The large hemispheres overcome this rigidity in the work of the subcortical nodes both in relation to irritation and in relation to inhibition. Weak external and internal irritations, insufficient for the direct excitation of subcortical centers, excite them with the help of the large hemispheres. Pavlov suggests that perhaps in the large hemispheres the summation of new irritation with traces of old ones takes place - the accumulation of irritations. For the inhibition of subcortical centers from the side of the large hemispheres, a weak irritation of the latter is also sufficient: it is possible that here too the large hemispheres gradually accumulate inhibition to make it strong enough to overcome the direct strong irritation of the subcortical centers. In general, according to Pavlov, the large hemispheres perform the following work for the subcortical centers: first, they analyze and synthesize both the external and the internal world of the animal, and second, they constantly correct the rigidity of the subcortical centers. Pavlov considers that the reverse influence of the subcortical centers on the large hemispheres is 'no less significant than that of the hemispheres on them; the active state of the large hemispheres is constantly maintained due to irritations coming from the subcortical centers'. Thus, the increase in food excitability achieved by reducing the food portion (i.e., excitation of the hunger instinct) changes the character and magnitude of conditioned reflexes. A similar phenomenon is also observed with a decrease in food excitability.

A. Geymanovich. Subcortical Area and Effectiveness. The activity of the thalamus and centers of the autonomic nervous system is a necessary condition for the occurrence of affects and emotions. The thalamus represents a central switching station for conductors of sensitivity, in which all centripetal nerve fibers coming from the periphery and conducting irritations from sense organs end, and central neurons begin, conducting the same irritations to various areas of the cerebral cortex. According to L. R. Müller, it is precisely at this switching that sensations acquire an emotional coloration, a shade of accompanying feelings of pleasure or displeasure; in particular, it is precisely due to the activity of the thalamus, according to Müller, that pain arises. On the other hand, according to the same theory, switching of irritations from animal sensitivity conductors to fibers of the autonomic nervous system also occurs in the thalamus. Confirmation of Müller's theory are the observations of Head on patients with thalamus lesions. According to Head, 'the sensory tone of somatic or visceral sensations is a result of thalamic activity'. In the patients he observed, the same painful irritation on the side of the lesion was felt more painful. One of them claimed that his hand on the affected side always had a need for caress, sympathy (see Thalamus opticus - thalamic syndrome). The active side of affectivity, including the expression of affects, is inextricably linked to the activity of the autonomic nervous system, the higher centers of which are located in the subcortical area. Through these centers, excitations going from the cerebral cortex as well as directly from sense organs are transmitted to the periphery. Autonomic innervation determines all those somatic changes that play a decisive role in the expression and in the very experience of affect (see). Drives, which form the basis of many affective states, such as sexual desires, hunger, thirst, etc., are also largely under the influence of the autonomic nervous system and arise due to impulses transmitted from its subcortical centers (see Drive). The close connection existing between the activity of the endocrine apparatus and affectivity is explained by the fact that the centers of the autonomic nervous system, on the one hand, control endocrine functions, and on the other hand, are themselves under the influence of circulating hormones in the blood. Subcortical regulation of somatic affective manifestations, being only one component of a complex psychological process, occurs to a large extent independently of volitional impulses and consciousness. This circumstance explains the observed, for example, in hysterics, automatization and detachment from consciousness of a number of functions that are voluntary under other conditions, as well as the reverse phenomenon: the influence of hypnosis, on the one hand, and unconscious desires and fears on the other, on such somatic functions that usually remain independent of the psyche (see Hypnotism, Hysteria).

^p- Zinoviev.