A Coronary-Prone Type of Personality: Peculiarities of Event-Related EEG Potentials

In a group of 70 adults of both sexes, we examined interrelations between the estimates of expression of a coronary-prone type (type A) of the personality (measured using the Jenkins questionnaire) and the parameters of event-related EEG potentials (ERPs). The latter potentials were recorded in the course of performance of two behavioral test tasks including motor components. Within the framework of the “A” task, the subject is had to maximally rapidly push the button after a signal with warning (with measurement of the latency of the sensorimotor reaction); under these conditions, we recorded the contingent negative variation (CNV) and P300 potential. In the case of the “B” task, a definite time interval was to be measured and limited by two pressings of the button. In this task, the readiness potential (RP) was recorded in addition to the CNV and P300. The C3 and C4 EEG leads (according to the 10–20 system) were used. Within the framework of the “A” task, subjects belonging to the coronary-prone type were characterized by the lowest amplitudes of the CNV and its separate components and also by greater amplitudes and relatively long latencies of the P300 wave. Persons of type B were distinguished by the highest CNV amplitudes in both hemispheres, while values of the P300 amplitude in this group were usually medium. In the “B” task, representatives of type A demonstrated the lowest RP and P300 amplitudes, especially clearly pronounced negative CNVs in the left hemisphere, and relatively long P300 latencies; individuals belonging to type B showed the highest RP and CNV amplitudes in the right hemisphere and medium values of the P300 amplitude. The correlations found are probably due, to a considerable extent, to the fact that both characteristics of the behavioral types A and B and amplitude parameters of ERPs depend significantly on genetically determined neurochemical factors, namely specificities of organization and functioning of a few neurotransmitter (in particular, aminergic) and neurohumoral systems.     

Wavelet entropy in event-related potentials: a new method shows ordering of EEG oscillations

 In this work we show the application of a measure of entropy defined from the wavelet transform, namely the wavelet entropy (WS), to the study of event-related potentials (ERPs). WS was computed for ERPs recorded from nine healthy subjects with three different types of stimuli, among them target stimuli in a cognitive task. A significant decrease of entropy was correlated with the responses to target stimuli (P300), thus showing that these responses correspond to a more “ordered” state than the spontaneous EEG. Furthermore, we propose the WS as a quantitative measure for such transitions between EEG (“disordered state”) and ERP (“ordered state”). Received: 12 April 2000 / Accepted in revised form: 11 September 2000     

Peculiarities of Activation of the Shoulder Belt and Shoulder Muscles in Generation of Different-Direction Isometric Efforts by the Forearm

We studied central motor commands, CMCs, coming to the muscles that flex and extend the shoulder and elbow joints in the course of generation of voluntary isometric efforts of different directions by the forearm; the efforts were initiated according to a visual signal. Amplitudes of EMGs recorded from the muscles of the shoulder belt and shoulder and subjected to full-wave rectification and low-frequency filtration were considered correlates of the CMC intensity. An effort of the preset direction was developed within the operational space of the horizontal plane with angles 30 deg in the shoulder joint (external angle with respect to the frontal plane) and 90 deg in the elbow joint. We plotted sector diagrams of the logarithmic coefficient of the intensity increment of EMGs of the above muscles for the entire set of directions of generated efforts with a 15- or 20-deg step. Orientations of the maxima of EMG activity of the given muscles were rather close to the directions of the maxima of the force moments generated by these muscles. In most cases, a shift of the direction by one gradation with respect to the EMG maximum in the respective muscle resulted in a significant decrease in the level of EMG activity. It is shown that preferential activation of the muscles agonistic with respect to the examined direction of the generated effort was, as a rule, accompanied by coactivation of the antagonist muscles. When “two-joint” isometric efforts are formed, realization of the socalled synergic muscle tasks (where prevailing contractions of the muscles of the same functional direction for both joints coincide, i.e., flexion-flexion or extension-extension) is organized in a simpler manner. The programs of “nonsynergic” contractions (flexion of one joint and extension of another one, or vice versa) are more complex. In different subjects, considerably dissimilar patterns of EMG activity in muscles influencing these joints could be observed.     

Correlations between the psychological peculiarities of an individual and the efficacy of a single neurofeedback session (by the EEG characteristics)

Modifications of different EEG rhythms induced by a single neurofeedback session (by the EEG characteristics) directed toward an increase in the ratio of the spectral powers (SPs) of the α vs θ oscillations were compared with the psychological characteristics of the tested subjects (the group included 30 persons). A generally accepted neurofeedback technique was used; the intensity of acoustic white noise served as the feedback signal. EEG potentials were recorded from the C3 and C4 leads. Psychological testing was carried out using Eysenck’s (EPQ), Rusalov’s (OST), and (16 PF) questionnaires. The directions of changes in the SPs of EEG frequency components were found to significantly correlate with some individuality-related peculiarities of the tested subjects. The SP of the δ rhythm correlated with the EPQ scale “neuroticism,” OST scale “social plasticity,” and 16 PF factors H (“parmia”), I (“premsia”), and Q₃ (“self-control of behavior”). The SP of the θ component demonstrated correlations with the OST scales “ergisity,” “plasticity,” and “social temp” and with 16 PF factors M (“autia”), Q₄ (“frustration”), and Q1 (“exvia”). The SP of the α rhythm correlated with 16 PF factors Q₃ (“self-control of behavior”), G (“strength of superEgo”), O (“hypothymia”), L (“protension”), and N (“shrewdness”). The SP of the β rhythm correlated with the OST scale “emotionality,” while that of the γ rhythm showed correlations with the 16 PF indices L (“protension”) and M (“autia”). Changes in the ratio of the α vs θ SPs correlated with the EPQ scale “neuroticism.” Thus, our data confirm the statement that a high individual variability of the results of a single (first in the series) neurofeedback session is to a great extent related to peculiarities of the individual psychological pattern of the subject. Neirofiziologiya/Neurophysiology, Vol. 38, No. 3, pp. 239–247, May–June, 2006.     

A control model of human tongue movements in speech

Tongue movements during speech production have been investigated by means of a simple yet realistic biomechanical model, based on a finite elements modeling of soft tissues, in the framework of the equilibrium point hypothesis (-model) of motor control. In particular, the model has been applied to the estimation of the “central” control commands issued to the muscles, for a data set of mid-sagittal digitized tracings of vocal tract shape, r ecorded by means of low-intensity X-ray cineradiographies during speech. In spite of the highly non-linear mapping between the shape of the oral cavity and its acoustic consequences, the organization of control commands preserves the peculiar spatial organization of vowel phonemes in acoustic space. A factor analysis of control commands, which have been decomposed into independent or “orthogonal” muscle groups, has shown that, in spite of the great mobility of the tongue and the highly complex arrangement of tongue muscles, its movements can be explained in terms of the activation of a small number of independent muscle groups, each corresponding to an elementary or “primitive” movement. These results are consistent with the hypothesis that the tongue is controlled by a small number of independent “articulators”, for which a precise biomechanical substrate is provided. The influence of the effect of jaw and hyoid movements on tongue equilibrium has also bee n evaluated, suggesting that the bony structures cannot be considered as a moving frame of reference, but, indeed, there may be a substantial interaction between them and the tongue, that may only be accounted for by a “global” model. The reported results also define a simple control model for the tongue and, in analogy with similar modelling studies, they suggest that, because of the peculiar geometrical arrangement of tongue muscles, the central nervous system (CNS) may not need a de tailed representation of tongue mechanics but rather may make use of a relatively small number of muscle synergies, that are invariant over the whole space of tongue configurations. Received: 27 August 1996 / Accepted in revised form: 25 February 1997     

Features of endocrine and cardiovascular response to emotional stress in subjects with different types of temperament

Functional features of endocrine and cardiovascular response to examination stress were investigated in 105 students of the Medical Academy who were divided into three groups according to their temperament types. Subjects with the “Apollon” type of temperament were found to have an adequate response to emotional stress. Subjects with the “Epimetei” type of temperament were characterized by the inert response of the regulatory and effector body systems, which was a prerequisite for the development of endocrine and cardiovascular disturbances. The prevalence of parasympathetic activity in the dynamics of emotional stress in subjects of the “Dionisii” type of temperament is indicative of their resistance to the harmful effect of stress. The preliminary psychological evaluation of the type of temperament makes possible the prognosis of adaptive reactions to stress or dysadaptation.     

The relationships between EEG θ and β oscillations and the level of creativity

The interrelations between the level of creativity and both the baseline power and event-related desynchronization/synchronization (ED/ES) of θ and β rhythms during a figural creative task (Torrance’s “Incomplete Figures” test) were studied under the conditions of different motivations. A higher motivation was caused by instruction “to create most unique images” as opposed to the instruction “to create images.” The subjects, right-handed students (14 males and 14 females), were divided into two groups with high and low originality scores (OSs). The baseline power and the ED/ES of the θ₂ and β rhythms of the subjects were found to depend on the level of creativity and person’s sex only in response to the instruction “to create images.” Male subjects with higher OSs differed from those with lower OSs in a stronger ED of the θ₂ rhythm in temporal-parietal-occipital brain regions, whereas these differences were absent in female subjects. Task performance was accompanied by ED of β₁ rhythm in men with higher OSs, whereas in women with higher OSs, ES was recorded in the same band. Only in women with high OSs did analysis of β_{1, 2} reference power show a higher β₁ power in the caudal hemispheric regions as compared to the frontal ones. High-OS subjects of different genders also differed in the lateral patterns of activity in the electrode loci Fp_1/2 (β₁) and Fp_1/2, F_7/8 (β₂). Our results suggest that a high level of creativity in men and women is related to sex-dependent specific patterns of frontal-occipital and lateral activities of θ and β rhythm oscillators in the brain cortex.     

Multiform wave organization of neurophysiological processes-universal “language” of human brain in realization of informational-controlling functions

The paper summarizes literature data and results of many-year Laboratory studies disclosing principles of the multiform spatial-time organization of differing by rates of neurophysiologic brain processes as the universal “language” of its informational-controlling functions. There are considered current concepts of electrogenesis and physiological significance of ratios of gradual changes of biopotentials and impulse activity of neurons considered in studies of cerebral mechanisms of regulation of normal and pathological states, and organization of human psychic activity. Put forward and argumented are concepts of the probability principle of hierarchical organization of differing by rates of neurophysiologic processes brain zones, structures, and areas in formation of the brain systems participating in provision of the higher psychic functions and states. It is proposed to discuss the concept of the brain as the “swimming,” many-contour, neurodynamic informational-controlling suprasystem with universal, hierarchically organized neurodynamic structures—”functional organs” by A.A. Ukhtomskii (1978), of which formation provides large informational brain capacity and a wide specter of adaptive possibilities of the human organism.     

Nerves in the endodermal canals of hydromedusae and their role in swimming inhibition

N eoturris breviconis (Anthomedusae) has a nerve plexus in the walls of its endodermal canals. The plexus is distinct from the ectodermal nerve plexuses supplying the radial and circular muscles in the ectoderm and no connections have been observed between them. Stimulation of the endodermal plexus evokes electrical events recorded extracellularly as “E” potentials. These propagate through all areas where the plexus has been shown by immunohistology to exist and nowhere else. When Neoturris is ingesting food, trains of “E” potentials propagate down the radial canals to the margin and cause inhibition of swimming. This response is distinct from the inhibition of swimming associated with contractions of the radial muscles but both may play a part in feeding and involve chemoreceptors. Preliminary observations suggest that the “E” system occurs in other medusae including Aglantha digitale (Trachymedusae) where the conduction pathway was previously thought to be an excitable epithelium.     

Correlative formation of functions as one of mechanisms of functional evolution (by example of development in child’s ontogenesis of central maintenance of stereognosis and speech function)

The paper considers a possibility of correlative formation in ontogenesis of central mechanisms of stereognosis and speech function by example of comparison of changes in spatial organization of interregional interaction of various cortex areas in children of three age groups (5–6, 7–8, and 9–10 years) and in adults subjects during their performances of stereognostical, verbalmnestic, and motor manual activity (the tapping test). With age dynamics of children there was observed a significant increase in the degree of similarity of the spatial structure of interregional relations during periods of performance of stereognostical test with patterns of changes in the EEG distant relationships revealed at performance of verbal tasks. In turn, similarity of patterns of interregional EEG relationships characteristic of stereognostical tasks with the patterns revealed at periods of performance of the tapping test was not increased with age. On the whole, the obtained data allow believing that with increase of children’s age there rose the degree of topological similarity of the spatial structure of systemic interactions of the cortex zones, on which there were “supported” processes of realization of stereognostical and verbal functions. The progressing increase with children’s age of the degree of similarity of the distributive organization of neurophysiological mechanisms of central provision of the verbal and stereognostic functions can argue in favor of the concept of correlative formation of these higher psychical functions in postnatal ontogenesis. The obtained data show that the correlative interfunctional interactions promoting progressive development of cognitive functions in the child ontogenesis can be realized through the long association fibers and commissural pathways composing the morphofunctional longitudinal-transversal “skeleton” of neocortex in the close interaction with thalamo-cortical integrative systems.     

A theory of steady-state activity in nerve-fiber networks II: The simple circuit

It is found that for a simple circuit of neurons, if this contains an odd number of inhibitory fibers, or none at all, or if the product of the activity parameters is less than unity, then the stimulus pattern always determines uniquely the steady-state activity. For circuits not of one of these types, it is possible to classify exclusively and exhaustively all possible activity patterns into three types, here called “odd”, “even”, and “mixed”. For any pattern of odd type and any pattern of even type there always exists a stimulus pattern consistent with both, but in no other way can such an association of activity patterns be made.     

Muscles within muscles: the neuromotor control of intra-muscular segments

The aim of this investigation was to anatomically identify, and then determine the function of, individual segments within the human deltoid muscle. The anatomical structure of the deltoid was determined through dissection and/or observation of the shoulder girdles of 11 male cadavers (aged 65–84 years). These results indicate that the deltoid consists of seven anatomical segments (D1–D7) based upon the distinctive arrangement of each segment's origin and insertion. Radiographic analysis of a cadaveric shoulder joint suggested that only the postero-medial segment D7 has a line of action directed below the shoulder joint's axis of rotation. The functional role of each individual segment was then determined utilising an electromyographic (EMG) technique. Seven miniature (1 mm active plate; 7 mm interelectrode distance) bipolar surface electrodes were positioned over the proximal portion of each segment's muscle belly in 18 male and female subjects (18–30 years). EMG waveforms were then recorded during the production of rapid isometric shoulder abduction and adduction force impulses with the shoulder joint in 40 degrees of abduction in the plane of the scapula. Each subject randomly performed 15 abduction and 15 adduction isometric force impulses following a short familiarisation period. All subjects received visual feed back on the duration and amplitude of each isometric force impulse produced via a visual force-time display which compared subject performance to a criterion force-time curve. Movement time was 400 ms (time-to-peak isometric force) at an intensity level of 50% maximal voluntary contraction. Temporal and intensity analyses of the EMG waveforms, as well as temporal analysis of the isometric force impulses, revealed the neuromotor control strategies utilised by the CNS to control the activity of each muscle segment. The results showed that segmental neuromotor control strategies differ across the breadth of the muscle and that individual segments of the deltoid can be identified as having either “prime mover”, “synergist”, “stabiliser” or “antagonist” functions; functional classifications normally associated with whole muscle function. Therefore, it was concluded that the CNS can “fine tune” the activity of at least six discrete segments within the human deltoid muscle to efficiently meet the demands of the imposed motor task. Accepted: 15 December 1997     

Association between contrasting methane emissions of two rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.) cultivars from the irrigated agroecosystem of northeast India and their growth and photosynthetic characteristics

Over two consecutive years in the North Bank Plain Zone of Assam, India, during the spring growing season (February–June) of- 2006 and 2007 we examined effects of morpho-physiological characteristics of rice (Oryza sativa L.) plants in relation to methane (CH₄) emission from paddy fields. Traditional cultivar “Agni” and modern improved cultivar “Ranjit” were grown in light textured loamy soil under irrigation. A higher seasonal integrated methane flux (E _sif) was recorded from “Agni” compared to “Ranjit”. Both cultivars exhibited an emission peak during active vegetative growth and a second peak at panicle initiation. Leaf and tiller number, leaf area, length, and volume of root were greater in “Agni”, but grain yield and yield-related parameters such as increased photosynthate partitioning to panicles at the expense of roots were greater in “Ranjit”. “Ranjit” also photosynthesed faster than “Agni” during panicle development but slower than “Agni” at tillering. In both the years, a higher soil organic carbon content was recorded in plots of “Agni”. Our results suggest that in “Agni” enhanced diversion of photosynthate to roots resulted in more substrate being available to methanogenic bacteria in the rhizosphere. Additionally, the more extensive vegetative growth of this cultivar may enhance methane transport from the soil to the above-ground atmosphere.     

Resolving the dynamics of EEG generators by multichannel recordings

The voltage recorded over the cortex (ECoG) or over the scalp (EEG) is generated by currents derived from many sources called “generators”. Different patterns and amplitudes are observed in aroused, sleepy, epileptic or other brain states. Differences in amplitude are generally attributed to differences in synchrony among generators. The degree of EEG synchrony is measured by the correlation between electrodes placed over different cortical regions. We present a new way to quantitatively assess the degree of synchronization of these generators via multichannel recordings. We illustrate how situations where there are several groups of generators with different inter-group and intra-group synchronies can be analyzed. Finally, we present a way to identify the organization of groups exhibiting topographic organization. Although the model presented here is highly simplified, several methods are based on averaging activity over increasingly larger areas. These types of measurements may be applied as well to EEG and ECoG recordings.     

Two types of using of space in the resident common shrews <Emphasis Type="Italic">Sorex araneus</Emphasis> L.

The home range of resident animals is considered as “familiar area” including a “foraging area.” It has been revealed that the activity of an average animal unit in the “foraging area” could be approximated by normal distribution. Estimation of activity distribution in the “familiar area” (beyond the “foraging area”) was impeded by means of marking since it might be difficult to record distant movements, and the method does not provide an essential body of data. In the case of the common shrew Sorex araneus, the “familiar area” was estimated using pitfall as animals evade them in the known areal. The “foraging area” radius of the average shrew was taken to be 30 m (95% of the animal unit activity), the radius of “familiar area” was within the range of 180–240 m. The “foraging area” was expected to provide the animal with vital resources, and the “familiar area” reflects its need for exploratory activity.     

Cell-pool tryptophan phases in ergot alkaloid fermentation

Three cell-pool tryptophan phases are recorded as characteristics of the alkaloid fermentation byClaviceps paspali grown on a simple defined medium without tryptophan. Within the early phase designated “tryptophan down” the alkaloid-biosynthetic activity of the mycelium attains the maximum, protein synthesis is reduced and extracellular proteases are formed. Cell-pool tryptophan level (b) drops, tryptophan synthetase activity (c) intensifies and sums of logb+logc after different time intervals remain constant. In the subsequent “tryptophan up” phase tryptophan level (b) increases, alkaloid yield (a) becomes a function of time and reaches the top level still tolerable by tryptophan synthetase. The difference of the logb—logc is constant. The tryptophan synthetase diminishes its activity simultaneously with the alkaloid-biosynthetic activity of the mycelium. The district between the “tryptophan down” and “tryptophan up” phase is an especially promising target for the investigation of the regulation of alkaloid formation and continuous fermentation of these compounds. During the third, i.e. “tryptophan over” phase, cell-pool tryptophan accumulates and attains a concentration exerting a negative effect on the alkaloid biosynthesis.     

Basidiocarp development inCoprinus macrorhizus

The dikaryon #5026 (A2B2)+#5132 (A7B7) of the basidiomyceteCoprinus macrorhizus was treated with ultraviolet light (UV),N-methyl-N′-nitro-N-nitrosoguanidine (NG), and 5-bromouracil (BU) in order to induced developmental variations in fruiting. Among a total of 11,383 isolates, 742 were homokaryons. Fruiting test was made with the remaining 10,641 dikaryotic isolates, of which 1,594 showed abnormality in basidiocarp development. Both UV and NG were very efficient in inducing such variations, but BU was not. The induced variations were classified into seven basic types as follows: 1) “knotless”, in which hyphal knots, the first sign of fruiting, do not differentiate; 2) “primordiumless,” in which hyphal knots are formed, but no further development occurs; 3) “maturationles”, in which primordia are formed, but the maturation of primordia into adult fruit bodies does not occur; 4) “elongationless”, in which the elongation of stipe is blocked, and a basidiocarp with a very short stipe is produced; 5) “expansionless,” in which pilei do not expand normally; 6) “sporeless,” in which the formation of basidiospores is blocked and albinic pilei bearing none or only a small amount of spores are produced; and 7) “autolysisless,” in which the autolysis of pilei does not appear to occur. It has been noticed that the four steps of maturation, i.e. stipe elongation, pileus expansion, spore formation, and perhaps pileus autolysis, can proceed independently. Compound types of variations such as “elongation-expansionless,” “elongation-sporeless,” “expansion-sporeless,” and “elongation-expansion-sporeless” were also induced. UV treatment induced maturationless at the highest rate, while NG treatment sporeless. Contributions from the Division of Plant Morphology, Department of Biology, Faculty of Science, Okayama University. No. 117.     

Pregnancy outcome of women in the vicinity of nuclear power plants in Taiwan

The purpose of the study was to investigate whether proximity to nuclear power plants may increase the risk of abnormal pregnant outcomes among the resident women. In this ecological study, data were used from the Health Services Birth Reports Database established by the Bureau of Health Promotion, National Department of Health, Taiwan, in 2001–2004. Chi-square-tests were carried out to investigate the “Plant-vicinity” and “Non plant-vicinity” group in terms of pregnancy outcome. Additionally, logistic regression was performed to investigate whether residence in the vicinity of a nuclear power plant was related to any abnormal pregnancy results. Based on data from 5,679 included subjects, no difference was observed between pregnancy outcomes of the “Plant-vicinity” and “Non plant-vicinity” groups. After accounting for possible confounders, the adjusted odds ratios were 1.20 (95% CI = 0.56–2.56) for stillbirth, 1.21 (95% CI = 0.95–1.53) for premature birth, 1.04 (95% CI = 0.79–1.37) for low birth weight, and 1.58 (95% CI = 0.85–2.93) for congenital deficiencies, respectively, when comparing the “Plant-vicinity” with the “Non plant-vicinity” group. The results of the study indicate that residence in the vicinity of a nuclear power plant is not a significant factor which will cause abnormal health situations during pregnancy.     

A quantum model for controlled enzymic reactions: II. Controlled biochemical networks

Two control units, the switching and the two factor discriminating net are described. They are derived as a consequence of the enzymic oscillatory behavior induced by substrate “perturbation”. A complex network encompassing long sequences of metabolic reactions is constructed and the organization of cellular metabolic activities in well defined “regimes” and “states” inferred.     

Microheological properties of different erythrocyte populations in persons with elevated arterial pressure and in physically active persons

Microrheological properties (aggregation and deformability) of erythrocytes separated by centrifugation at 30000×g density gradient into “young” and “old” (the upper and lower fractions, respectively) were studied. The erythrocytes were taken from physically active persons (PAP) and from those with elevated arterial pressure (EAP). A significant difference in microrheological properties of the “young” and “old” erythrocytes was found. The aggregation degree of “old” cells was nearly twice that of “young” cells. The deformability of the erythrocyte subpopulations was significantly different, though the difference was not so pronounced as in the case of aggregation. The aggregation of “young” and “old” erythrocytes in the PAP group was the least (28% lower than in the control). Note, that “old” erythrocytes in the PAP group had better microrheological properties than in the other groups. All erythrocyte populations in the EAP group were characterized by higher aggregation, decreased deformability, and decreased capacity for oxygen transport.