Hemodynamics (general and cerebral) and mental activity under normal conditions

Interrelations between the mental work efficiency and changes in total and cerebral hemodynamics during mental activity are considered. Five subgroups of the efficiency are distinguished. Changes in the vegetative reactions considerably differ in the type as well. Basic four types of such reactions are distinguished with allowance for changes in the character of minute blood circulation volume and cerebral blood flow. Comparison of changes in the efficiency of the activity with vegetative changes shows that in the process of the mental activity the vegetative changes are determined by interrelation between the intensity of the mental activity and its efficiency. It was concluded that the higher the activity efficiency, the lower the mental intensity and changes in the total and cerebral hemodynamics and, vice versa.     

WHO ARE PROSPECTIVE NEUROTICS?

Emotions of any kind and experienced at any age are etiologic factors of neuroses only in predisposed persons.Predisposed persons are those of neuropathic and psychoneuropathic constitution. This is characterized by excessive excitability and abnormal reactivity of the nervous system. This involves, in various degree and proportion, the autonomic nervous system as well as the higher cerebral functions including associative and emotional mental reactions.Objective signs of autonomic nervous imbalance can be detected by physical examination. In the mental sphere, psychoneurotic constitution can be recognized by emotional imbalance, excessive, inadequate, untimely reactions (“psychic dysmetry”).Neuropathic and psychoneuropathic constitution per se is compatible with perfect health. It deserves attention, however, in that its carriers may play an important role in cultural and social life and so exert a great suggestive influence on the mass of people.The type of neurosis or psychoneurosis and the symptoms of it depend chiefly on the constitutional morbid predisposition (constitutional biologic inferiority) of certain organs or organ systems and on the kind of emotional situations which the patient is unable to cope with.The great number of neuroses, psychoneuroses and psychosomatic diseases among patients consulting them makes it imperative that internists and general practitioners be capable of making the correct diagnosis and of carrying out the indicated treatments by “minor psychotherapy.”     

Psychic distress and the immune response

This minireview surveys recent progress in the field of immunoregulation by the central nervous system. Representative findings from human and animal studies show evidence for significant immunosuppression in states of psychic distress. Mechanisms of immunomodulation are discussed in light of data implicating neuroendocrine, genetic, neuroanatomical, and learning factors. Evidence for reciprocal modulation of immune and nervous systems is considered. A simple hierarchical model proposes traits that are acted on by environment and experience to produce chronic states of mental health vs. psychic distress; these states determine baseline immunocompetence and response to afferent signals during acute immune challenge. Multidisciplinary interest in psychoneuroimmunology has accelerated the rate of inquiry into the mechanistic details of immunoregulation and has generated new appreciation for the pervasive effects of mental status on physiologic homeostasis.     

Causal interactions between the cerebral cortex and the autonomic nervous system

Mental states such as stress and anxiety can cause heart disease.On the other hand,meditation can improve cardiac performance.In this study,the heart rate variability,directed transfer function and corrected conditional entropy were used to investigate the effects of mental tasks on cardiac performance,and the functional coupling between the cerebral cortex and the heart.When subjects tried to decrease their heart rate by volition,the sympathetic nervous system was inhibited and the heart rate decreased.When subjects tried to increase their heart rate by volition,the parasympathetic nervous system was inhibited and the sympathetic nervous system was stimulated,and the heart rate increased.When autonomic nervous system activity was regulated by mental tasks,the information flow from the post-central areas to the pre-central areas of the cerebral cortex increased,and there was greater coupling between the brain and the heart.Use of directed transfer function and corrected conditional entropy techniques enabled analysis of electroencephalographic recordings,and of the information flow causing functional coupling between the brain and the heart.     

Comparative aspects of a study of the self-regulation of higher nervous activity in experimental neuroses in dogs, cats and rats

The higher nervous activity has been studied by means of motor-alimentary conditioned reflexes and delayed reactions in dogs, cats and albino rats at early stages of development of experimental informational neurosis. It was shown that formation of stable pathological reactions is preceeded by self- regulational activity of the brain directed towards elimination of a pathological situation, as well as to the increase of the stability of the nervous system to pathogenic agents. Comparative studies on rodents and predatory animals indicate that in different species the same pathogenic effects on the brain may elicit different forms of self-regulation of the higher nervous activity.     

Sweating response to abrupt changes in work load

Changes in sweat rate on the palm and on the general body surface in response to stepwise increases and decreases in work load during exercise on a bicycle ergometer were examined in relation to body temperature and heart rate in six male subjects (three trained and three untrained), in an attempt to evaluate thermal and nonthermal factors responsible for those changes. In all the untrained subjects, a transient, marked increase in palmar sweat rate was observed upon an abrupt increase (and occasionally upon an abrupt decrease) in work, while an increase in sweat rate on the general body surface was also rapid and marked. On the other hand, in all the trained subjects, palmar sweat rate was low and hardly showed a substantial increase in response to an abrupt increase in work load, to which sweating on the general body surface responded slowly by a gradual increase. While sweat rate on the general body surface showed a significant correlation with esophageal temperature and with heart rate, palmar sweat rate was not correlated with esophageal temperature but was significantly correlated with heart rate. Moreover, repeated increases and decreases in work load often led to progressive weakening of palmar sweating due apparently to the development of habituation. The present results suggest that responses of sweating to stepwise changes in work load are not solely dependent upon the thermoregulatory mechanism but are affected considerably by increase and decrease in psychic excitement and/or those in discharges of the sympathetic nervous system accompanying changes in work load.(ABSTRACT TRUNCATED AT 250 WORDS)     

Physiological basis and image processing in functional magnetic resonance imaging: Neuronal and motor activity in brain

Functional magnetic resonance imaging (fMRI) is recently developing as imaging modality used for mapping hemodynamics of neuronal and motor event related tissue blood oxygen level dependence (BOLD) in terms of brain activation. Image processing is performed by segmentation and registration methods. Segmentation algorithms provide brain surface-based analysis, automated anatomical labeling of cortical fields in magnetic resonance data sets based on oxygen metabolic state. Registration algorithms provide geometric features using two or more imaging modalities to assure clinically useful neuronal and motor information of brain activation. This review article summarizes the physiological basis of fMRI signal, its origin, contrast enhancement, physical factors, anatomical labeling by segmentation, registration approaches with examples of visual and motor activity in brain. Latest developments are reviewed for clinical applications of fMRI along with other different neurophysiological and imaging modalities.     

Spatial organization and genetic information in brain development

In the course of brain development neurons acquire qualitative and quantitative biochemical and morphological properties which depend on the position of the cells within the nervous system. In the dimensions tangential to multilayered cell sheets mechanisms contributing to spatial order include induction by adjacent tissue as well as internal generation of morphogenetic fields (presumably by reactions involving autocatalysis and lateral inhibition). In the dimensions across the sheet cells of different types are produced in one layer and sort into another layer, guided presumably by contact mediated cell interaction. Positional and directional cues encoded in the developing brain are essentially involved in axonal guidance and the formation of neuronal connections. In mammals and man, the number of neurons and their connections in the brain is much higher than the number of genes. This is possible because there are repetitive neuronal circuits in the brain, and there is topographic order of connections between different brain areas. For instance, few quantitatively graded markers would suffice for specifying the projection of one area of the nervous system onto another, generating spatial order for a large number of fibers while requiring only a limited amount of genetic information. Higher brain functions, such as learning and memory, may logically require only a neural network consisting of repetitive subunits. On the other hand, it is an evolutionary advantage for an organism to be endowed, from the outset, with a pattern of neural connections which is subtly and quantitatively tuned for efficiency in dealing with the environment, while remaining flexible for change and adaptation in the course of learning. Estimates are given suggesting that a considerable part of the genetic information in DNA may be invested for such quantitative specification of connections within the brain.     

Activities of hexokinase, phosphofructokinase, 3-oxo acid coenzyme A-transferase and aceto-acetyl-coenzyme A thiolase in nervous tissue from vertebrates and invertebrates

1. The maximum activities of hexokinase and phosphofructokinase in nervous tissue from 18 different animals from different phyla range from 5.1 to 17.6 and from 24.0mumol/min per g fresh wt. respectively. In any one tissue the activities of these two enzymes are, in general, very similar. The rate of glucose utilization by the brain in vivo is much lower than the activities of hexokinase or phosphofructokinase. It is suggested that the high activities of these enzymes indicate a capacity for glycolysis which may be used by the brain during hypoxia or during conditions of extreme neuronal activity. 2. The activities of 3-oxo acid CoA-transferase and acetoacetyl-CoA thiolase in the nervous tissues range from 1.1 to 15.3 and from 0.7 to 4.5mumol/min per g fresh wt. respectively. Unfortunately the activities of these enzymes cannot be used to estimate maximal flux through the ketone-body-utilization pathway, since they may catalyse reactions that are close to equilibrium. Nonetheless, the presence of these enzymes in nervous tissue from a large variety of animals suggests that the importance of ketone bodies as a fuel for nervous tissue may be widespread in the animal kingdom.     

Norepinephrine transporter（NET）is expressed in cardiac sympathetic ganglia of adult rat

INTRODUCTIONThe sympathetic nervous system (SNS) plays animportant role in regulating cardiac function in bothhealth and disease through releasing neurotransmit-ter norepinephrine (NE). 1n central nervous sys-tem (CNS), the neurotransmission of NE is terminated tbIough reuptaxe of released neurotransndt-ter by Na , Cl---dependent norepineplirine trans-porter (NET) on pre--synaPtic membrane[1, 2]. ALthough the NE uptake was well studied in heaxt, butthe molecular basis fOr that is s…     

The influence of examination stress on psychophysiological characteristics and heart rate in students

With the aim to assess the influence of pre-examination psychoemotional stress on the level of centralization of the heart rate control, mathematical analysis of ECG of students was performed in normal condition (a common day of academic semester), before, and after an examination. The ECG was recorded and processed with the help of IBM-486 PC. R-R cardiointevalograms were processed by the method of variational pulsometry after Baevsky. Common quantitative heart rate indices were studied. The level of anxiety of students was assessed by Spilberger, and subjective estimations of general condition, activity and mood were obtained from the respective questionnaire. Three types of heart rate reactions on the examination stress were revealed. The reactions depended on the individual typological characteristics and the state of autonomic nervous system.     

A clinical and neuropsychological analysis of mental functions in 6- to 7-year-old children

The neuropsychological analysis of the state of higher mental functions (HMF) in children aged 6-7-years entering the first class of the school providing general education showed that the HMF of 52-73% of the future schoolchildren are underdeveloped with respect to their age. The underdevelopment of the emotional-volitional sphere, of the dynamic organization of object activity, audio-speech memory, sphere of images-representations, visually-image and verbally-logical forms of thinking has been revealed. The experimental data suggest the absence of the primary (structural) derangements of the studied HMF in the examined children and dependence of the extent of their formation on the extent of readiness of the voluntary organization of activity. Insufficient formation of the HMF with respect to age is manifested in the lag of the formation of the internal structure of the psychic process, i.e., the absence of interiorization of the psychic processes and formation of the internal mental act. The neuropsychological assessment of underdevelopment of the HMF in reference to age suggests an insufficient age-related maturity of subcortical structures and subcortical corticopetal pathways as well as a dysfunction of the frontal neocortex and a secondary dysfunction of the posterofrontal and TPO areas, non-auditory cortical temporal regions of the left hemisphere due to underdevelopment of connections of these areas with the frontal structures.     

Selective fixation of methylselenobenzoic acid by the pineal gland]

Investigation of the localization in the central nervous system of the rat of an epileptogenic agent, methylseleno-2-benzoic acid, did not lead to its selective distribution in the cerebral cortex or in the brainstem in relation with its biological activity. But a systematic study of the distribution of this compound labelled with 75Se at a high specific activity has revealed a rate of fixation by the pineal gland 4 to 5 times higher than that of other tissues of the central nervous system. After a survival time of 4 hours, the radioactivity of the pineal gland exceeds that of the blood. A parallel study of the distribution of the 75SeO3- ion on the one hand of the 35S homolog of the 75Se compound on the other hand has demonstrated that the fixation by the pineal gland is bound to the molecular structure of the selenium compound.     

Norepinephrine transporter heterozygous knockout mice exhibit altered transport and behavior

The norepinephrine (NE) transporter (NET) regulates synaptic NE availability for noradrenergic signaling in the brain and sympathetic nervous system. Although genetic variation leading to a loss of NET expression has been implicated in psychiatric and cardiovascular disorders, complete NET deficiency has not been found in people, limiting the utility of NET knockout mice as a model for genetically driven NET dysfunction. Here, we investigate NET expression in NET heterozygous knockout male mice (NET^+/?), demonstrating that they display an approximately 50% reduction in NET protein levels. Surprisingly, these mice display no significant deficit in NET activity assessed in hippocampal and cortical synaptosomes. We found that this compensation in NET activity was due to enhanced activity of surface‐resident transporters, as opposed to surface recruitment of NET protein or compensation through other transport mechanisms, including serotonin, dopamine or organic cation transporters. We hypothesize that loss of NET protein in the NET^+/? mouse establishes an activated state of existing surface NET proteins. The NET^+/? mice exhibit increased anxiety in the open field and light–dark box and display deficits in reversal learning in the Morris water maze. These data suggest that recovery of near basal activity in NET^+/? mice appears to be insufficient to limit anxiety responses or support cognitive performance that might involve noradrenergic neurotransmission. The NET^+/? mice represent a unique model to study the loss and resultant compensatory changes in NET that may be relevant to behavior and physiology in human NET deficiency disorders .     

Improving general flexibility with a mind-body approach: a randomized, controlled trial using neuro emotional Technique®

General flexibility is a key component of health, well-being, and general physical conditioning. Reduced flexibility has both physical and mental/emotional etiologies and can lead to musculoskeletal injuries and athletic underperformance. Few studies have tested the effectiveness of a mind-body therapy on general flexibility. The aim of this study was to investigate if Neuro Emotional Technique? (NET), a mind-body technique shown to be effective in reducing stress, can also improve general flexibility. The sit-and-reach test (SR) score was used as a measure of general flexibility. Forty-five healthy participants were recruited from the general population and assessed for their initial SR score before being randomly allocated to receive (a) two 20-minute sessions of NET (experimental group); (b) two 20-minute sessions of stretching instruction (active control group); or (c) no intervention or instruction (passive control group). After intervention, the participants were reassessed in a similar manner by the same blind assessor. The participants also answered questions about demographics, usual water and caffeine consumption, and activity level, and they completed an anxiety/mood psychometric preintervention and postintervention. The mean (SD) change in the SR score was +3.1 cm (2.5) in the NET group, +1.2 cm (2.3) in the active control group and +1.0 cm (2.6) in the passive control group. Although all the 3 groups showed some improvement, the improvement in the NET group was statistically significant when compared with that of either the passive controls (p = 0.015) or the active controls (p = 0.021). This study suggests that NET could provide an effective treatment in improving general flexibility. A larger study is required to confirm these findings and also to assess longer term effectiveness of this therapy on general flexibility.     

连续胸椎旁神经阻滞联合全身麻醉对乳腺癌根治手术患者血流动力学、应激反应及生存质量的影响

摘要 目的：探讨连续胸椎旁神经阻滞（TPVB）联合全身麻醉对乳腺癌根治手术患者血流动力学、应激反应及生存质量的影响。方法：选择2017年2月~2019年8月期间于我院行乳腺癌根治手术的乳腺癌患者125例,按照随机数字表法分为A组62例和B组63例,A组给予全身麻醉,B组给予TPVB联合全身麻醉,对比两组血流动力学、应激反应、生存质量、疼痛及不良反应。结果：两组插管前（T1）~拔管时（T4）时间点平均动脉压（MAP）、心率（HR）均较麻醉前（T0）升高,但B组T1~T4时间点MAP、HR低于A组（P<0.05）。B组术后1 d肾上腺素、血糖、去甲肾上腺素及多巴胺水平低于A组（P<0.05）。两组术后6个月躯体角色、躯体功能、情感角色、社会功能、躯体疼痛、总体健康、活力以及心理健康评分均较术前升高（P<0.05）。B组术后4 h、术后12 h、术后24 h安静时视觉模拟评分法（VAS）评分 、运动时VAS评分低于A组（P<0.05）。两组不良反应总发生率对比未见统计学差异（P>0.05）。结论：TPVB联合全身麻醉应用于乳腺癌根治手术患者,可减轻机体应激反应,维持血流动力学平稳,减轻术后疼痛,且不增加不良反应发生率,对生存质量无显著影响。     

Cardiovascular reactivity to mental stress: relationship with menstrual cycle and gender

The purpose of the present study was to determine the fluctuation in cardiovascular reactivity to mental stress during the menstrual cycle by comparing heart rate variability (HRV), and other physiological and psychological data in females with those in males. Cardiovascular reactivity to two mental tasks was measured in 14 females during the follicular and luteal phase of menstruation over two menstrual cycles. The same tasks were subsequently given to a matched pair of males (N=14), at the same intervals as their corresponding females. Heart rate, blood pressure and HRV were used as indices of cardiovascular reactivity. Subjective mental workload was measured at the end of each task. Power spectral analysis of HRV showed that the high frequency (HF) component in HRV decreased more during the luteal phase than the follicular phase. The low frequency (LF) component in HRV and the LF/HF ratio in the luteal phase were significantly higher than that in the follicular phase. The LF component and the LF/HF ratio were significantly lower in females than in males; conversely, the HF component was significantly higher in females than in males. Neither significant effects of menstrual cycle, gender and mental stress nor any significant interactions were found for mental workload. These findings indicate that sympathetic nervous activity in the luteal phase is significantly greater than in the follicular phase whereas parasympathetic nervous activity is predominant in the follicular phase. The results also suggest that predominance of sympathetic nervous activity in males compared with a dominant parasympathetic nervous activity in females.     

The neurotropic effects of low-intensity electromagnetic waves in rats with different typological characteristics of higher nervous activity

The effects of the ultralow-intensity electromagnetic fields (EMF, frequency of 4200 and 970 MHz, modulated by a quasistochastic signal in the range of 20-20,000 Hz, power density 15 microW/cm2, specific body absorption rate up to 4.5 mJ/kg) on the reactions of the central nervous system (CNS) of rats with different types of behavior were studied. Some neurochemical and behavioral mechanisms of rats' reactions were investigated. It was shown that the EMF produce pronounced changes in the state and activity of monoaminergic brain systems. These changes, on the whole, correspond to the alterations at the integrative level (predominantly, of the inhibitory character).     

The dynamics of intracortical interaction during thinking activities

A new method is described of the brain mapping, based on determination of the probability of appearance of isofrequency components in the EEG derivations allowing to evaluate functional interaction of the brain structures in the process of psychic activity. The process of mental construction of visual image from separate elements includes three stages. At the stage of image search the focus of activity is in the occipital cortical area; in the stage of construction it moves to the frontal cortical areas; completion of the task and verbalization of the image are accompanied by joining of the cortical connections in common system. Alongside with the main focus of activity secondary focuses in the temporal cortex are also revealed during the search of the visual image. The topography of interaction at the frequencies of alpha-range in mainly determined by the stage of image construction. In case of prevalence of the image and abstract thinking shift is marked of the activity focuses at the frequencies of theta-range respectively to the right and left hemispheres.     

Characteristics of memory and the functional organization of the hippocampo-reticulo-neocortical complex of the brain in the acute postoperative period

In tests on dogs, rabbits and rats, it has been established that in acute postoperative period, the time of memorizing of conditioned signals (light, tone and metronome) is reduced, the time of realization of conditioned reactions increases, the excitability and the bloodflow of the midbrain reticular formation and Mg-AtPhase activity of pons Varolii raise. In the hippocampus the excitability and local bloodflow lower and the activity of Ca-Mg-ATPhase is enhanced. In the frontal cortex these processes do not change. Functional interrelations of the brain structures in the acute postoperative period are characterized by the weakening of the activating influence of the reticular formation on the frontal cortex and an increase of its suppressive action on the dorsal hippocampus. It is suggested, that the discovered damages in the higher nervous activity are stipulated by the changes in neurochemical organization of the brain.