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PubMed2003

[Clinical characteristics and gender identity among eating disordered patients subtypes].

BACKGROUND: Gender identity is a relevant issue in the approach to eating disorders. AIM: To compare psychological and behavioural characteristics and traits of gender identity among women with eating disorders and its subtypes and non eating disordered female subjects. MATERIAL AND METHODS: An structured clinical interview based on the DSM-IV diagnostic criteria for eating disorders, the EAT-40 (Eating Attitudes Test), the Eating Disorders Inventory (EDI) and the Bem Sex Role Inventory (IBRS) were administered to 58 compulsive-purgative anorectics (AN/BN group), 15 restrictive anorectics (AN group), 33 patients suffering from eating disorder not otherwise identified, 33 purgative bulimics and to 82 female students without eating disorders. RESULTS: Patients with eating disorders ranked significantly higher on the EAT-40 and EDI and all its items (p < 0.001). The AN/BN group ranked significantly higher on the EDI (p < 0.001) and on Drive for thinness, Perfectionism and interpersonal distrust (p < 0.001). The AN group ranked higher on Maturity fears (p < 0.001). The BN group ranged higher on Body dissatisfaction, Ineffectiveness and Interoceptive awareness (p < 0.001). Patients with eating disorders were significantly identified with Feminine category and subjects without eating disorders with Androgynous and Undifferentiated categories on the IBRS (p = 0.002). The AN group showed the highest percentage on Feminine category and the lowest on Androgynous and Undifferentiated categories. All the groups rejected and approved feminine, masculine and neutral qualities. CONCLUSIONS: Femininity emerged as the main trait of gender identity in patients suffering from eating disorders, in contrast to androgyny, showed by healthy women.

Adult↗

PubMedDate not supplied

[Preliminary validation of the French translation of anxiety sensibility index-revised (ASI-R)].

Anxiety sensitivity represents a stimulus-outcome expectancy that reflects individual differences in the propensity to experience fear in response to one's arousal-related bodily sensations. It refers to the fear of anxiety-related symptoms that are based on beliefs that such sensations have negative somatic, social or psychological consequences. Anxiety sensitivity occupies an important place in theory and research on panic and related interoceptive fear disorders. Findings from this body of research indicate that this construct may act as a specific vulnerability variable in the development of panic attacks and anxiety symptoms. However, anxiety sensitivity theory also has been applied to understanding mood disorders and chronic pain disorders. Thus, as a psychological construct, anxiety sensitivity holds specific relevance to understanding panic disorders and general relevance for expanding knowledge about negative emotional functioning in other pathologies. All the research on anxiety sensitivity has been completed with the 16-item Anxiety Sensitivity Index (ASI). The review of the literature using this instrument suggested that anxiety sensitivity has three lower-order factors that all load on a single higher-order factor. The lower-order factors represent Physical-Concerns, Mental Incapacitation Concerns, and Social Concerns, and the higher-order factor represents the global anxiety sensitivity construct (21). Taylor and Cox (22) suggested that this questionnaire was not designed on an a priori basis to measure the identified lower-order factors. The low number of items for the Social and Mental Incapacitation dimensions of the 16-item ASI often leads to relatively lower levels of reliability compared to the third dimension. To address this issue, Taylor and Cox (22) developed an expanded measure of the anxiety sensitivity construct. The 36-item Revised Anxiety Sensitivity Index (ASI-R) maintains the same format as the 16-item ASI, but expands the number of content domains assessed. The ASI-R was designed to assess 6 lower-order domains identified in previous factor analytic research using the 16-item ASI (21), including fear of cardiovascular symptoms, fear of respiratory symptoms, fear of gastrointestinal symptoms, fear of publicity observable reactions, fear of dissociative and neurological symptoms, and fear of cognitive dyscontrol. The principal components factor analysis using the ASI-R among psychiatric outpatients indicated that there were 4 lower-order factors tapping the constructs of (1) fear of respiratory symptoms, (2) fear of publicly observable anxiety reactions, (3) fear of cardiovascular symptoms, and (4) fear of cognitive dyscontrol (22). A recent study (27) provided an initial psychometric evaluation of the ASI-R in a large, diverse sample of people (n = 2,786) from 6 different countries: Canada, United States, Mexico, Spain, The Netherlands and France. The data suggested that the two-factor solution is most replicable than other solutions (2 to 6 factors). The underlying structure of the anxiety sensitivity construct was generally similar across countries, tapping fear about the negative consequences of anxiety-related physical and social-cognitive sensations. Lower-order factors were moderately to strongly correlated with one another and showed good internal consistency. This manuscript presents the French translation of the ASI-R and a preliminary validation study. This research was realized conjointly with the transcultural study previously mentioned (27). Seven hundred and one French university students (non-clinical participants) completed the questionnaire at the beginning of a class. Subjects were undergraduate students from 2 universities (psychology and classics). Table I provides age, sex and marital status. There were no differences between the two groups on sex. The two groups were not comparable on age and marital status. The psychology group was older than the other was. The psychology students were also more married. The total group (n = 701) comprises 79 men and 622 women, with a mean age of 21.29 (4.85). Table II provides the normative means and standard deviations for both groups of students. There was no difference between the two groups on the total of the questionnaire (no significant interaction between group and age). In regard to the physical concerns subscale and the social-cognitive concerns subscale, there was also no significant interaction between group and age. Assessment of the internal consistency of the ASI-R yielded an overall Cronbach alpha of 0.91 for the entire questionnaire, with an alpha of 0.88 for the fear of anxiety-related physical sensations subscale and 0.83 for the fear of anxiety-related social-cognitive sensations subscale. A series of ANOVAs between male and female groups revealed significant gender differences. As shown in table IV, women had significantly higher total score than did men. They also had significantly higher physical factor and social-cognitive factor scores than did men. This finding is consistent with research that indicates that women generally report more intense fears and men less intense fears, and that they differ in levels of overall anxiety sensitivity specifically (29). This preliminary report was the first attempt to examine the construct of anxiety sensitivity using the ASI-R in a French university students. It can serve as a reference point for future research.

Adult↗

PubMedDate not supplied

[The use of prostatilen in treating patients with prostatic diseases].

A clinical trial of polypeptide prostatic preparation prostatilen has been performed in 37 and 15 patients with chronic prostatitis and prostatic adenoma, respectively. The treatment resulted in attenuation of algetic and dysuria symptoms. Copulative function and spermatogenesis improved. The uroflowmetric index rose, while residual urine and leukocyte count in prostatic secretion reduced. The drug demonstrated antibacterial and immunomodulation effects in the absence of adverse reactions. Prostatilen is indicated in: chronic prostatitis, prostatic adenoma stage I, normospermatogenic and toxic sterility, interoceptive copulative dysfunction, dysuria. The drug in recommended for clinical application.

Adult↗

PubMed1990

Late EEG after-effects in humans following hyperventilation. II. A comparison between subjects with different level of adaptation to hypoxia.

The late EEG after-effects following application of a short-lasting ventilatory interoceptive influence (3 min hyperventilation-HV) were studied in humans with three degrees of adaptation: students (ST) with a lower degree of training, professional alpine climbers with a high level of training (AL1) and the same subjects (AL2) in a middle position of adaptation i.e. 6 months after an expedition. ST developed late EEG after-effects, consisting mainly in an increase of the beta-2 EEG activity; AL1 showed very slight changes, while in AL2 the EEG after-effects were intermediate. It is suggested, that a lower level of adaptation facilitates the triggering through HV of processes in the cortical EEG which accompany an improvement of the brain tone.

Adaptation, Physiological↗

PubMed1990

The adaptive base of the neural hierarchy: elementary motivational controls on network function.

This chapter has explored a hierarchical approach to motivation, based on the idea of a vertical integration among brainstem, limbic, paralimbic, and neocortical systems. When viewed in the traditional manner, this hierarchy has been seen in terms of top-down control, with the neocortical regions exerting higher-level, converging influences over the lower regions. When viewed from an evolutionary perspective, the hierarchy proves to be balanced by a complementary pattern of divergent projections ascending from the lower to the higher levels. These ascending systems respond first to the adaptively significant properties of a stimulus, including its novelty, conspicuousness, and need relatedness. By means of their increasingly specific projection patterns, the elementary motivational mechanisms support a progressive narrowing of activity within the cortex. Selection begins with activity in ascending brainstem systems, organizing the primordial states of tonic activation and phasic arousal. Although these states are relatively general, they bias information processing in specific ways by modulating both the spatial and temporal span of attention. As limbic circuits are recruited, certain classes of adaptive response and perceptual processes are potentiated, bringing into play postural orientations and global perceptions of the environment. This response and perceptual processing promotes activity within the interoceptive fields of the paralimbic cortices, leading to primitive hedonic and energetic representations. Back-projections from paralimbic to successive neocortical fields allow these affective representations to aid further in narrowing sensory and response options. Multiple levels of representation thus work together in gradually focusing and articulating the representations forming within the hierarchical networks of the neocortex. The recent evidence on neocortical architecture shows that cortical areas tend to be most closely connected with other regions of the same level of architectonic differentiation. Thus the functional units of the cortex may be not lobes or even hemispheres but the growth rings sharing a specific laminar architecture and dense horizontal interconnections. Functional binding--the integration of the distributed representations of the cortex--may take place across these horizontal lines. Furthermore, the density of horizontal interconnections decreases for the more recently evolved neocortical growth rings, such that the primary and sensory and motor cortices are relatively isolated from all but the adjacent architectonic ring. This suggests that the most important functional binding in the cortex occurs at the more primitive, paralimbic network levels.(ABSTRACT TRUNCATED AT 400 WORDS)

Brain↗

PubMed1990

The anatomy of the visceral and autonomic nervous systems.

The visceral nervous system has several levels of anatomical organization. Individual viscera, including the heart and the intestines, have neural tissue embedded in their walls that is capable, under some circumstances, of a truly autonomic self-regulation of that organ's activity. This self-regulation will not respond to all the varying needs of the organ control, particularly when external or internal changes affect the whole animal. The parasympathetic, sympathetic, and visceral afferent systems and their CNS connections are the next level of reflex neural organization. A greater degree of central regulation is managed at this level. The third level of visceral control is located in the brainstem and includes the hypothalamus, parts of the reticular formation, and cardiorespiratory centers in the medulla. These visceral upper neuron centers exert a high degree of control over the parasympathetic and sympathetic LMN centers of the brainstem and spinal cord. The reticulobulbar and reticulospinal pathways are the means by which the visceral upper motor neurons communicate with the LMN systems. The hypothalamus-hypophyseal system exerts control by releasing hormones to act on distant target organs. The highest level of organization of visceral function takes place in the limbic system. The limbic system is in a position to integrate sensory information originating from both within (interoceptive) and outside (exteroceptive) the animal. Associations are made at this level and with the help of cortical association areas, memory is integrated with these sensations. The limbic system is then able to influence the hypothalamic and medullary centers as well as the somatic motor centers to develop the appropriate responses for the preservation of the animal.

Afferent Pathways↗

PubMed1990

[Stress, behavior and disease].

For those who have attempted to attach some importance to the problem, the role played by psychological factors in disease usually is reduced to a doctrinal choice between psychoanalytic connotations and a mechanism theory based on the biology of stress. The boundaries of this choice have enormously evolved during these last years and the results of the psychobiologic approach allow us to leave this bipolar quarrel aside. The notion of stress invariably suggests the idea of a common final pathway through which environmental aggression influence the psychological equilibrium and visceral function. This notion is obsolete. Our organism has specific defence mechanisms according to the nature of the aggression. Each of these systems relies on the close relationship existing between visceral reactions and behaviour. They differ, however, by their trigger mechanisms and the somatic and psychic modalities of expression. The exteroceptive defence system is the best known. It is activated by any external aggression susceptible of endangering the animal's (including man) physical or mental being. The behaviour pattern which arises from this reaction depends on the species, but varies according to the possibilities of prevision and control of the aggression. The same is true for their hormonal and autonomous components. In the interoceptive defence system, it is essentially the gastrointestinal components related to acquired gustative aversion that have been studied. Poisoning due to ingestion of spoiled food provokes an aversion to the aliment responsible, based on its organoleptic characteristics. The mechanisms that differ according to whether the aliment can be expelled by vomiting or by acceleration of intestinal transit.(ABSTRACT TRUNCATED AT 250 WORDS)

Aggression↗

PubMed1990

[Intestinal sensitivity disorders and irritable bowel syndrome].

Long neglected in the past, the study of visceral sensitivity (interoception) has progressed in recent years because of advances in neurobiological techniques. Dealing with the structure or the function of single neurons, these techniques have profoundly increased our knowledge about the sensitive mechanisms in the digestive tract. According to recent data, the visceral sensitivity organs are richer and more complex than imagined previously. Microphysiological techniques have shown that intestinal sensitive terminations are capable of transmitting information concerning visceral activity and physicochemical modifications of intestinal contents directly to the central nervous system. This means that visceral sensitivity intervenes under physiological as well as pathological conditions. This notion is new and of great interest. As progress was being made concerning the morphologic and electrophysiologic aspects and contemporaneous studies were establishing the richness of visceral, and particularly, intestinal, sensitive receptors, basic science research in humans and animals have emphasized the diversity of the implication of the extrinsic nervous system in pain, regulation of digestive motility, homeostasis and alimentary behaviour. Our present knowledge on the nervous and neurohumoral mechanisms has shed new light on the determinisms in digestive tract pathology. This is especially true in the irritable bowel syndrome which can be considered as an extrinsic nervous system derangement. Due to abnormal sensitivity by modification of the threshold values of sensitivity to distension, and/or to stimulation by substances such as cholecystokinin, for example, motor disorders occur. Other factors, such as stress, can be responsible for revelation or exacerbation of neurohumoral disorders.

Colonic Diseases, Functional↗

PubMed1989

Effects of competitive and noncompetitive N-methyl-D-aspartate (NMDA) antagonists in rats trained to discriminate NMDA from saline.

Competitive and noncompetitive N-methyl-D-aspartate (NMDA) antagonists and other central nervous system depressants were assessed for their ability to antagonize the discriminative stimulus effects of NMDA in rats trained under a standard two-lever fixed ratio schedule of food reinforcement. The competitive NMDA antagonists, 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonate and NPC 12626 [2-amino-4,5-(1,2-cyclohexyl)-7-phosphonoheptanoate], dose-dependently antagonized NMDA-lever selection at doses that did not affect rates of responding. Conversely, the noncompetitive NMDA antagonists, phencyclidine, MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5,10-imine maleate] and (+)-N-allylnormetazocine, as well as pentobarbital and diazepa, all reduced response rates dose-dependently without antagonism of NMDA-lever responding. In stimulus generalization tests, NPC 12626 and 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonate at doses higher than those required to antagonize NMDA, often elicited NMDA-lever responding. The mechanisms underlying the similarities in the interoceptive stimuli produced by NMDA and its competitive antagonists remain to be determined. These results indicate that although competitive NMDA antagonists antagonize effects of NMDA without concomitant behavioral disruption, noncompetitive NMDA antagonists and central nervous system depressants are behaviorally disruptive at doses that do not antagonize NMDA. The results provide further evidence for differences in the behavioral profiles of competitive and noncompetitive NMDA antagonists.

Amino Acids↗

PubMed1989

Ultrastructural demonstration of a gastric monosynaptic vagal circuit in the nucleus of the solitary tract in rat.

Previous light microscopic work in the rat has demonstrated that many dendrites of vagal gastric motoneurons extend beyond the cytoarchitectural boundaries of the dorsal motor nucleus of the vagus (DMV) into the nucleus of the solitary tract (NST), where they overlap with the central terminal field of vagal gastric primary sensory neurons (Shapiro and Miselis, 1985a). In the present ultrastructural study, the synaptic relationship of vagal afferent terminals and vagal motor neurons and dendrites was examined. Following injection of cholera toxin-HRP conjugate (CT-HRP) into the dorsal and ventral musculature of the stomach wall, centrally transported tracer was visualized using tetramethylbenzidine or diaminobenzidine histochemistry. Light microscopy confirmed the presence of retrogradely labeled gastric DMV neurons whose dendrites extended into the overlying NST. The subnucleus gelatinosus of the dorsomedial NST at a level just rostral to the obex contained the highest density of vagal motoneuronal dendrites coextensive with transganglionically labeled vagal sensory afferents. Ultrastructural analysis of several NST subfields at this rostrocaudal level revealed many asymmetric synaptic contacts between labeled sensory afferents and labeled motoneuronal dendrites in the subnucleus gelatinosus but not elsewhere. Following CT-HRP injection into the cervical vagus nerve in separate animals, vagovagal synaptic contacts were again observed only in the subnucleus gelatinosus, despite extensive afferent labeling in other NST subnuclei. The demonstration of a monosynaptic gastric vagovagal circuit provides the anatomical substrate for the relay of gastric interoceptive information directly to gastric vagal motoneurons, which may play a unique role in the central regulation of gastric motility and secretion.

Animals↗

PubMedDate not supplied

Somatostatin 28-immunoreactive inputs to the paraventricular and supraoptic nuclei: principal origin from non-aminergic neurons in the nucleus of the solitary tract.

Immunohistochemical and axonal transport methods were used to chart the distribution of somatostatin-immunoreactive (SS-IR) fibres in the paraventricular (PVH) and supraoptic (SO) nuclei of the rat hypothalamus and to identify the cell group(s) from which they originate. Fibres and varicosities immunoreactive for SS-28 and/or SS-281-12 are found primarily in the parvocellular division of the PVH, though aspects of the magnocellular division, and of the SO, in which oxytocinergic neurons are clustered also receive moderate inputs. Combined retrograde transport-immunohistochemical studies indicated that these arise principally from non-catecholaminergic neurons in the lateral aspect of the commissural part of the nucleus of the solitary tract (NTS). SS-28 has been shown to act within the central nervous system to elicit both oxytocin and vasopressin secretory responses, and may be involved in mediating vasopressin secretory responses to haemorrhage. Direct SS-28-IR inputs to the magnocellular cell groups from the NTS, which receives primary visceral sensory inputs, are in a position to play a role in mediating oxytocin secretory responses to interoceptive stimuli; the pathway(s) and mechanism(s) which allow SS-28 to interact with vasopressinergic neurons are not clear.

Animals↗

PubMed1985

Localization, colocalization, and plasticity of corticotropin-releasing factor immunoreactivity in rat brain.

The generation of antiserums against a peptide that has met the criteria predicted for corticotropin-releasing factor (CRF) has allowed the immunohistochemical localization of CRF immunoreactive neurons in the rat brain. Although CRF-stained cells have been found to be widely distributed in the central nervous system, attention has focused on neurons in the paraventricular nucleus of the hypothalamus (PVH), which is now acknowledged to be the principal source for delivery of CRF to the hypophyseal portal system. Some 2000 CRF-stained neurons can be counted in the PVH of the colchicine-treated rat, and there is evidence that enkephalin, PHI, and neurotensin coexist with CRF in subsets of parvocellular neurons. Consistent with the established negative feedback effects of adrenal steroids on CRF production and release, adrenalectomy enhances CRF immunoreactivity in parvocellular neurosecretory neurons in the PVH. In addition, immunoreactive vasopressin can be demonstrated in a majority of CRF-stained parvocellular neurons after adrenalectomy, which suggests a form of plasticity that allows for synergy of the two peptides in stimulating adrenocorticotropin secretion. The effects of adrenalectomy appear to be glucocorticoid-dependent, and specific to these peptides and this cell type. A survey of neural inputs to the hypophyseotropic zone of the PVH suggests potential substrates for the control of CRF release and/or synthesis by interoceptive stimuli, by the limbic region, and by a number of cell groups in the basal forebrain. Finally, CRF may also participate in other (nonadenohypophyseal) modes of regulation that are represented in the PVH. Thus, CRF immunoreactivity has been demonstrated in a discrete subset of oxytocinergic magnocellular neurosecretory neurons that project to the posterior pituitary, and in a small fraction of cells in the parvocellular division that project to cell groups in the brain stem and spinal cord that are associated with the control of autonomic functions.

Adrenalectomy↗

PubMed1987

[Various elements in the construction of the theory of a metasympathetic nervous system].

Structural and functional evidence determines the metasympathetic nervous system as the third, independent portion of the autonomic (vegetative) nervous system. Problems of its onto- and phylogenesis, evolutionary advances of its relative independence, interrelationship among electrical behaviour of neurons, integrative function of nets' local neurons, transmitter mechanisms in every link of the reflex arch of this level, are considered. Neurobiological properties, structural-organizational similarity to the brain nuclear formations connections of the metasympathetic nervous system with the central nervous system and its relationships with sympathetic and parasympathetic systems, are discussed. The metasympathetic system is suggested to perform basic control over the majority of visceral organs. The concept unites V. N. Tchernigovsky's theory of interoception and K. M. Bykov's theory of cortico-visceral relationships, advancing each of them.

Animals↗

PubMed1987

[Comparative physiologic study of the responses of cerebellar cortex neurons to stimulation of the vagus nerve].

The cerebellar cortex neuronal responses (of Purkinje cells--PC, and of unidentified neurons UN) to vagus stimulation in anesthetized pigeons, rats and monkeys were actualized as spikes or as complex discharges in PC. Tonic neuronal responses were mainly excitatory. All the PC and the majority of UN were polymodal. Differences in the line: birds--mammals, started with an increase of responsiveness, particularly on account of mossy fibers input. A shortening of neuronal responses latency was observed. In monkeys only, a lengthening of inhibitory pauses and a variability of afterdischarges were found. The significance of cerebellum in interoceptive information processing seems to increase in phylogenesis.

Animals↗

PubMed1987

[Pharmacological correction of the acute effects of microwave irradiation in an experiment].

Possible ways of correction of acute effects developing in organism under the intensive microwave radiation (AMWE) are considered. The literature review demonstrates that the pharmacological preparations which cause stimulation of the supreme sections of the central nervous system (CNS) and breathing (analeptics, psychostimulants), an elevation of the vascular tone (adrenomimetics), an increase of the heart working capacity (cardiac glycosides) and an increase of energetic metabolism level (some hormones and vitamins) are suitable for the AMWE correction. For the AMWE prevention before radiation the drugs reducing excitability of CNS (sleeping draughts) oppressing the interoceptive reflexes (neuroplegic drugs) and antihypoxiac drugs can be used.

Acute Disease↗

PubMed1985

Discriminative stimuli produced by clonidine in spontaneously hypertensive rats: generalization to antihypertensive drugs with different mechanisms of action.

Spontaneously hypertensive rats were food deprived and trained to lever press on a fixed-ratio 10 schedule of food reinforcement in a paradigm in which responding was reinforced on one lever after an injection of clonidine (0.02 mg/kg) and on an alternate lever after an injection of saline. The spontaneously hypertensive rats learned the clonidine-saline discrimination to a criterion of correct lever selection on 10 consecutive days in an average of 39 training sessions. In subsequent tests, emission of clonidine discrimination responses was found to be both time dependent and dose dependent (ED50, 0.009 mg/kg). The antihypertensive drugs lofexidine (ED50, 0.03 mg/kg), guanabenz (ED50, 0.019 mg/kg), p-aminoclonidine (ED50, 0.23 mg/kg), methyldopa (ED50, 21.8 mg/kg), hydralazine (ED50, 0.98 mg/kg), prazosin (ED50, 0.72 mg/kg), minoxidil (ED50, 12.4 mg/kg) and pergolide (ED50, 0.021 mg/kg) were generalized to clonidine in a dose-dependent manner. Yohimbine antagonized both the antihypertensive action and the discriminative stimulus properties of clonidine in parallel without antagonizing those actions of hydralazine. Similarly, the discriminative stimulus properties and antihypertensive action of pergolide were antagonized by sulpiride in parallel without antagonizing any of those effects when produced by clonidine or hydralazine. Although the stimulus properties and response-suppressive actions of the antihypertensive or other drugs were not related, the ED50 values for generalization of the drugs to the clonidine stimulus and for their antihypertensive action were highly correlated (r = 0.99). These data suggest that clonidine produces an interoceptive discriminative stimulus that is based upon its antihypertensive action in spontaneously hypertensive rats.

Animals↗

PubMed1979

Effect of experimental hydrothorax on the cough reflex in conscious cats.

The authors induced experimental hydrothorax in cats by injecting dextran into the pleural cavity under brief N2O anaesthesia. They examined the parameters of cough -- elicited by mechanical stimulation of the airway mucosa -- and blood gas and pH values under normal conditions and after the injection of 50, 100, 200 and 250 ml dextran. The tests were always performed 30 min after terminating anaesthesia, i.e. in conscious animals. The free fluid in the thorax was found, in conscious cats, to reduce the inspiratory values of cough, but to have no effect on cough expiration. This is in agreement with previous findings showing that the intensity of a cough expiration does not always depend on the intensity of the preceding cough inspiration. According to this finding, the decrease in the expiratory values of cough observed during experimental pleurisy cannot be due to the actual exudate. In cats, experimental hydrothorax in doses of 200 and 250 ml leads to respiratory insufficiency. The authors further found that, for the study of interoception in the airways of conscious cats, which requires experimental induction of pathological conditions under brief anaesthesia, nitrous oxide is a convenient anesthetic.

Animals↗

PubMedDate not supplied

[Neuronal mechanisms of sensory integration in the visual analyzer system].

It has been established in experiments on immobilized cats that somatic and interoceptive signals produce complex reorganizations of the spontaneous and evoked activity of visual cortex units. Either long diffuse changes of spike frequency or phasic reactions have been observed. The dynamics of sensory integration in the visual cortex is determined by unconditioned and conditioned mechanisms both of an intra- and interanalyser nature. Functioning of the microsystem of learning elements in the visual cortex is based on units capable of fixing the elaborated changes of evoked activity and constituting 18.6 percent of the total number of cellular elements in the visual projection cortex, responding to direct cortical stimulation. Microinophoresis of synaptically active agents has shown that complexely organized choline- and serotoninergic structures involved in the processes of unconditioned and conditioned interaction of heteromodal excitations are located in the visual cortex.

Acetylcholine↗