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1.
V. A. Ilyukhina 《Journal of Evolutionary Biochemistry and Physiology》2010,46(3):321-333
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. 相似文献
2.
Use of symbols, the key to the biosemiotics field as to many others, required bigger brains which implied a promissory note for greater energy consumption; symbols are obviously expensive. A score years before the current estimate of 18–20% for the human brain’s metabolic demand on the organism, it was known that neural tissue is metabolically dear. This paper first discusses two evolutionary responses to this demand, on both of which there is some consensus. The first, assigning care of altricial infants with burgeoning brains (and in human infants the metabolic demand peaks at 65% of the total) to “allomothers” is not unique to humans. The second, using relatively small neurons as primates do, risks misfires past a certain minimal value. Moreover, in apparent paradox, there is an increasing consensus that large “Von Economo” neurons are critical for communication. This paper’s main contribution is the discussion of two further evolutionary tricks. The first is the use of self-similarity in the cortex, both in structure and process, to allow the cortex readily—and in energetic terms, parsimoniously—to shift between states in a high-dimensional space. This leads to discussion of the kind of formalism appropriate to model these shifts, a formalism which—it is tentatively suggested—may do double duty for the modeling of symbolic thought. The second trick is the superimposition on the background “white noise” of neural firing of EEG-detected waves like gamma. The paper describes a method, using the Hilbert transform, of calculating the dips in energy consumption as the brain is transitioned by gamma waves. It is hypothesized that consciousness may be a spandrel, the incidental result of a neurodynamic imperative that the brain enter a maximally sensitive (in sensory terms) “zero power” state a few times a second. If that is the case, then there are obvious benefits for health in meditation, which can be viewed as a state of consciousness extended over time by limiting afferent stimuli. 相似文献
3.
I. N. Konareva 《Neurophysiology》2009,41(1):54-62
In a group of 70 adult subjects of both sexes, we estimated the levels of the need for achievement and its motivation (interpreted
as generalized characteristics of the state of the motivational sphere of a personality and diagnosed using questionnaires
of Orlov and Mehrabian) and examined the correlations of these estimates with spectral powers (SPs) of the frequency components
(rhythms) of the current background EEG (С3 and С4 leads according to the 10–20 system). Despite the fact that naturally high
interindividual variability exists, high estimates of the need for achievement correlated with medium values of the SPs of
most EEG frequency components (δ, θ, α, and β1 rhythms), low SPs of the β2 and γ rhythms, and higher values of the coefficient of reactivity (CR) of the α rhythm. A high level of the need for achievement
corresponded to higher SPs of the θ and γ rhythms and high CR of the α rhythm, a medium SP of this EEG component, and lower
SPs of the δ and β rhythms. The coefficient of interhemisphere asymmetry of the α rhythm was the highest at low values of
the studied psychological indices. Interrelations that we found in our study can be explained as follows: both the characteristics
of the need for achievement and motivation typical of a certain personality and the amplitude parameters of the EEG rhythms
observed in this individual depend significantly on genetically determined factors (in particular, on neurochemical ones).
These peculiarities of neurodynamic constitution of the individual are, to a considerable extent, due to the specificity of
organization and functioning of a few neurotransmitter (aminergic, in particular) and neurohumoral systems.
Neirofiziologiya/Neurophysiology, Vol. 41, No. 1, pp. 61–69, January–February, 2009. 相似文献
4.
I. N. Konareva 《Neurophysiology》2006,38(5-6):380-388
In a group of 80 adults of both sexes, we studied the correlation between the characteristics of aggressiveness of the individual
(diagnosed using the Buss-Durkee questionnaire) and parameters of the frequency components (rhythms) of EEG recorded in the
resting state from leads C3 and C4 according to the 10–20 system. Despite the natural high interindividual variability, the
higher spectral powers of nearly all EEG frequency components (δ-, θ-, α-, and β rhythms) and coefficient of reactivity of
the α rhythm corresponded in general to lower indices on the scales of the Buss-Durkee questionnaire and smaller values of
the index of aggressiveness and index of hostility. These correlations probably reflect a significant dependence of both characteristics
of aggressiveness of personality and amplitude parameters of the EEG rhythms on hereditary factors. Both these aspects of
the neurodynamic constitution of the individual are to a significant extent determined by the specificity of organization
and functioning of a few neurotransmitter (in particular, aminergic) and neurohumoral systems.
Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 448–457, September–December, 2006. 相似文献
5.
I. N. Konareva 《Neurophysiology》2011,43(2):131-141
In a group of 68 adults of both sexes, we examined correlations between estimates of the psychological adaptability of an
individual (diagnosed using a multilevel personality questionnaire, MPQ) and spectral powers, SPs, of the frequency components
(rhythms) of background EEG recorded in the resting state (leads C3 and C4 according to the 10–20 system). Despite high individual
variability within the group, indices by the scale “communicative potential” demonstrated significant correlation with the
SP of the θ rhythm, while estimates of the moral normativity correlated with the SPs of the α and β1 rhythms. Subgroups of
the persons classified according to the level of the integral adaptation capability (personality’s adaptation potential) differed
from each other in the mean estimates of interhemisphere asymmetry of the α rhythm; this index was higher in subjects with
the medium/high level of adaptability. The correlations observed are, most probably, determined by the fact that both the
level of psychological adaptability of the personality and the EEG amplitude parameters depend significantly on genetic (neurochemical,
in particular) factors. Such peculiarities of the neurodynamic constitution of the individual are probably determined, to
a considerable extent, by the specificities of organization and functioning of a few neurotransmitter (aminergic, in particular)
and neurohumoral systems. 相似文献
6.
I. N. Konareva 《Neurophysiology》2007,39(2):137-146
In a group of 76 adults of both sexes, we examined interrelations between the level of aggressiveness of the individual (diagnosed
using the Buss-Durkee Hostility Inventory) and parameters of event-related EEG potentials (ERPs) recorded under conditions
of two behavioral test acts including a motor component. Within the framework of task A, the subject must push a button with
the shortest delay after an executory signal preceded by a warning signal; the time of sensorimotor reaction was measured.
Under these conditions, we recorded the contingent negative variayion (CNV) and the P300 potential. In the case of task B,
it was necessary to measure a definite time interval limited by two pushings of the button. Under these conditions, the readiness
potential (RP) was recorded in addition to the CNV and P300. The C3 and C4 leads were used (according to the 10–20 system);
the time constant of an amplification tract was 10 sec. Despite natural broad interindividual variability, high amplitudes
of the recorded ERPs (RP, CNV, and P300) in general corresponded to lower indices by scales of the Buss-Durkee inventory and
smaller values of the indices of aggressiveness and hostility. These interrelations are, probably, based on the fact that
both characteristics of aggressiveness of the personality and EEG amplitude parameters are to a considerable extent determined
by hereditary factors. It is believed that the respective peculiarities of the neurodynamic constitution of the individual
are to a great extent dependent on the specificities of organization and functioning of a few neurotransmitter (in particular,
aminergic) and neurohumoral systems.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 2, pp. 154–164, March–April, 2007. 相似文献
7.
I. N. Konareva 《Neurophysiology》2011,42(4):286-293
In a group including 72 adults of both sexes, we studied correlations between the estimates of the so-called coronary-prone
personality type (type A) diagnosed using the Jenkins questionnaire and the spectral powers (SPs) of the frequency components
(rhythms) of background EEGs recorded in the resting state (leads C3 and C4 according to the 10-20 system). Despite natural
high interindividual variability, estimates that characterized the subject as belonging to the behavioral type A corresponded,
on average, to relatively low SPs of the δ, θ, and α EEG components, intermediate values of the β1 rhythm SP and coefficient of reactivity of the α rhythm, and higher SPs of the high-frequency (β2 and γ) rhythms. Estimates characterizing type B personality corresponded to significantly higher δ-rhythm SPs, intermediate
SPs of the θ and α rhythms, and smaller SPs of the β and γ rhythms. The interhemisphere asymmetry coefficient for the α rhythm
was usually negative in type-A individuals and positive in the cases of types B and AB. The peculiarities observed are probably
determined, to a certain extent, by the fact that both the characteristics of the behavioral types of the personality and
the amplitude parameters of EEG rhythms depend significantly on inherited (in particular neurochemical) factors. Such peculiarities
of the neurodynamic constitution of the individual are determined, to a considerable extent, by the specificity of organization
and functioning of a few neurotransmitter (in particular aminergic) and neurohumoral systems. 相似文献
8.
D. K. Kambarova V. V. Belyaev A. V. Volkova S. G. Oganesyan V. Z. El Salim G. A. Oganesyan 《Journal of Evolutionary Biochemistry and Physiology》2010,46(5):501-510
A possibility is discussed of use of methods of nonlinear dynamics for analysis of spontaneous EEG and of the EEG caused by
low acoustic stimuli in healthy people and in patients with epilepsy. The use of methods of nonlinear dynamics—the fractal
dimension of EEG—in clinical and scientific practice is described. 相似文献
9.
This article generalizes the results of many years’ studies of the EEG of patients with tumorous lesions in the diencephalic,
brainstem, and limbic structures, which fulfill the regulatory function in ensuring integral brain activity. The specific
features of the inclusion of individual structures under investigation in the organization of the intra- and interhemispheric
relations of cortical biopotentials were demonstrated against the background of diffuse changes in the biopotentials that
reflect the systemic character of neurodynamic reorganizations when the regulatory brain structures are involved in the pathological
process. This study expands the idea of the predominant functional connection of the diencephalic structures with the right
hemisphere and brainstem structures with the left one with determination of the regional specific features of changes in the
intrahemispheric EEG coherences. The distinguishing features of intercentral relations when the limbic structures are involved
in the pathological process show similarity with the neurodynamic reorganizations in patients with lesions in both diencephalic
and (even more so) brainstem structures. Universal elements were detected in the formation of integral adaptive reactions
of the brain with lesions in its regulatory structures, which reflects their close functional interaction and makes it possible
to consider them the individual links of an integral regulatory system. The study revealed reciprocal changes in various forms
of electrical activity, which reflects reciprocation of interaction of individual regulatory structures. This is one of the
EEG equivalents of the formation of adaptive-compensatory cerebral reactions. The specificity of influence of the studied
regulatory structures are clearly seen in situations of their morphofunctional isolation observed during cerebral coma. In
these conditions, when the cortex is functionally inactive, the authors demonstrated the dynamic character of changes in interhemispheric
asymmetry, which reflects the dominance of individual links of the regulatory system playing the role of supreme regulator
of life support of the body in critical states. 相似文献
10.
I. N. Konareva 《Neurophysiology》2009,41(5):346-354
We studied the relations between generalized characteristics of the state of the motivational sphere, the levels of need for
achievements (N-Ach) and achievement motivation (AchM) typical of an individual, and the parameters of cerebral event-related
potentials (ERPs). The examined group included 70 adults of both sexes. The ERPs were recorded in the course of realization
of two behavioral test acts with motor components. In task А, the subject should press a button with the minimum delay with
respect to an imperative signal preceded by a warning signal (with the measurement of the time of sensorimotor reaction);
in this case, the contingent negative variation (CNV) and Р300 potential were recorded. Under conditions of task B, the subject
should measure a definite time interval limiting the latter by two pushings of the button; in this case, the readiness potential
(RP) was recorded in addition to CNV and Р300. The ERPs were recorded in the С3 and С4 leads (according to the 10-20 system).
The peculiarities of the motivational sphere were diagnosed using Orlov’s and Mechrabian’s questionnaires. We found that a
relatively high amplitude of the early CNV component (СNV-O) and low amplitudes of the integral CNV and Р300 in task A and
a low amplitude of the RP can serve as task B-related EEG markers of a high NA level. In task A, high levels of the AchM correlated
with higher amplitudes of the CNV and Р300, and amplitudes of these potentials were higher in the left hemisphere. The observed
interrelations were probably determined by a considerable dependence of the N-Ach and AchM characteristics, on the one hand,
and CNV amplitude parameters, on the other hand, on the hereditary factors, in particular neurochemical ones. It is obvious
that such peculiarities of the neurodynamic constitution of an individual are, to a considerable extent, determined by the
specificity of organization and functioning of a few neurotransmitter (in particular aminergic) and neurohumoral systems. 相似文献
11.
The EEGs of 885 healthy subjects of both sexes aged 7 to 89 years were recorded in two modes: with the subjects’ eyes closed
and with the eyes open. The subjects were divided into 20 age groups, for each of which the normative values of the EEG spectral
characteristics were determined: the total EEG power spectra and the EEG independent component power spectra in the Δ, ϑ,
α, and β frequency bands. Tables of confidence intervals with a level of confidence of 0.95 were constructed for each electrode
channel in the case of the EEG power spectra and for each component in the case of the EEG independent component power spectra.
The normative values obtained may provide EEG specialists with objective criteria for assessing cerebral dysfunction. 相似文献
12.
Epicatechin belongs to flavonoids protecting cells against oxidative/nitrative stress. Oxidative/nitrative stress observed
in schizophrenia may be caused partially by the treatment of patients with various antipsychotics. The aim of our study was
to establish the effects of epicatechin and antipsychotics action (the first generation antipsychotic (FGA)—haloperidol and
the second generation antipsychotic (SGA)—amisulpride) on peroxidation of plasma lipids in vitro. Lipid peroxidation in human
plasma was measured by the level of thiobarbituric acid reactive species (TBARS). The properties of epicatechin were also
compared with the action of a well characterized antioxidative commercial polyphenol—resveratrol (3,4′,5-trihydroxystilbene)
and quercetin (3,5,7,3′,4′-pentahydroxyflavone). Amisulpride, contrary to haloperidol (after 1 and 24 h) does not significantly
influence the increase of plasma TBARS level in comparison with control samples (P > 0.05). After incubation (1 and 24 h) of plasma with haloperidol in the presence of epicatechin we observed a significantly
decreases the level of TBARS (P < 0.001, P < 0.001, respectively). In our other experiments, we found that epicatechin also decreased the amount of TBARS in human plasma
treated with amisulpride. In conclusion, the presented results indicate that epicatechin—the major polyphenolic component
of green tea reduced significantly human plasma lipid peroxidation caused by haloperidol. Moreover, epicatechin was found
to be a more effective antioxidant, than the solution of pure resveratrol or quercetin. 相似文献
13.
A component analysis of human neurodynamic and psychodynamic characters in the norm was carried out in 8 human populations characterized by different degrees of isolation and ethnic origin. An increase in phenotypic variability and a decrease in heritability with increasing complexity of organization of the characters under study were demonstrated for all these populations. The additive effect plays the major role in genetic determination of neurodynamic and psychodynamic characters studied. For a number of neurodynamic parameters the effect of intralocus dominance indicative of the oligogenic determination system was observed. Data in favour of real contribution of the factors linked to X-chromosome were obtained for simple sensomotor reactions. 相似文献
14.
Rudolf M. Dünki 《Bulletin of mathematical biology》1991,53(5):665-678
A method to estimate a lower bound of the Kolmogorov entropy—the so calledK
2-entropy—from a time series is presented which avoids use of the generalized correlation integral. The influence of the norm
is studied. The method is demonstrated on some standard examples. The entropy of the attractor apparent in the EEG of the
foetal sheep is estimated and the results are compared with results obtained from synthesized data featuring some basic properties
of EEG. This gives an insight into the limitations of the procedure. 相似文献
15.
LC-NMR: a new tool to expedite the dereplication and identification of natural products 总被引:1,自引:0,他引:1
The rapid identification of known or undesirable compounds from natural products extracts — “dereplication” — is an important
step in an efficiently run natural products discovery program. Dereplication strategies use analytical techniques and database
searching to determine the identity of an active compound at the earliest possible stage in the discovery process. In the
past few years, advances in technology have allowed the development of tandem analytical techniques such as liquid chromatography
mass spectrometry (LC-MS), LC-MS-MS, liquid chromatography nuclear magnetic resonance (LC-NMR), and LC-NMR-MS. LC-NMR, despite
its lower sensitivity as compared to LC-MS, provides a powerful tool for rapid identification of known compounds and identification
of structure classes of novel compounds. LC-NMR is especially useful in instances where the data from LC-MS are incomplete
or do not allow confident identification of the active component of a sample. LC-NMR has been used to identify the marine
alkaloid aaptamine as the active component in an extract of the sponge Aaptos sp. This extract had been identified as an enzyme inhibitor by a high throughput screening (HTS) effort. Isolated aaptamine
exhibited an IC50=120 μM against this enzyme. Strategies for the identification of aaptamine and for the use of LC-NMR in a natural products
HTS program are discussed. Journal of Industrial Microbiology & Biotechnology (2000) 25, 342–345.
Received 30 March 2000/ Accepted in revised form 03 July 2000 相似文献
16.
The aim of the present study was to develop and evaluate a buccal adhesive tablet containing ondansetron hydrochloride (OH).
Special punches and dies were fabricated and used while preparing buccal adhesive tablets. The tablets were prepared using
carbopol (CP 934), sodium alginate, sodium carboxymethylcellulose low viscosity (SCMC LV), and hydroxypropylmethylcellulose
(HPMC 15cps) as mucoadhsive polymers to impart mucoadhesion and ethyl cellulose to act as an impermeable backing layer. The
formulations were prepared by direct compression and characterized by different parameters such as weight uniformity, content
uniformity, thickness, hardness, swelling index, in vitro drug release studies, mucoadhesive strength, and ex vivo permeation study. As compared with the optimized formulation composed of OH—5 mg, CP 934—30 mg, SCMC LV—165 mg, PEG 6000—40 mg,
lactose—5 mg, magnesium stearate—1.5 mg, and aspartame—2 mg, which gave the maximum release (88.15%), non-bitter (OH) that
form namely ondansetron base and complexed ondansetron was used in order to make the selected formulation acceptable to human.
The result of the in vitro release studies and permeation studies through bovine buccal mucosa revealed that complexed ondansetron gave the maximum
release and permeation. The stability of drug in the optimized adhesive tablet was tested for 6 h in natural human saliva;
both the drug and device were found to be stable in natural human saliva. Thus, buccal adhesive tablet of ondansetron could
be an alternative route to bypass the hepatic first-pass metabolism and to improve the bioavailability of (OH). 相似文献
17.
The electroencephalogram (EEG) is a multiscaled signal consisting of several time-series components each with different dominant
frequency ranges and different origins. Nonlinear measures of the EEG reflect the complexity of the overall EEG, but not of
each component in it. The aim of this study is to examine effect of the sound and light (SL) stimulation on the complexity
of each component of the EEG. We used independent component analysis to obtain independent components of the EEG. The first
positive Lyapunov exponent (L1) was estimated as a nonlinear measure of complexity. Twelve subjects were administered photic
and auditory stimuli with a frequency of 10 Hz, which corresponded to the alpha frequency of the EEG, by a sound and light
entrainment device. We compared the L1 values of the EEGs and their independent components between baseline and after the
SL stimulation. We detected that the L1 values of the EEG decreased after the SL stimulation in all channels except C3 and
F4, indicating that the complexity of the EEG decreased. We showed that alpha components increased in proportion but decreased
in complexity after the SL stimulation. The beta independent components were found to decrease in proportion and complexity.
These results suggest that decreased complexity of the EEG after the SL stimulation may be principally caused by decreased
complexity and increased proportion of the alpha independent components. We showed also that theta components increased in
complexity after the SL stimulation. We propose that nonlinear dynamical analysis combined with independent component analysis
may be helpful in understanding the temporal characteristics of the EEG, which cannot be detected by conventional linear or
nonlinear methods.
Received: 12 March 2001 / Accepted in revised form: 27 November 2001 相似文献
18.
Topographic analysis of dimension estimates of EEG and filtered rhythms in epileptic patients with complex partial seizures 总被引:2,自引:0,他引:2
Nonlinear dynamic properties were analyzed on the EEG and filtered rhythms recorded from healthy subjects and epileptic patients
with complex partial seizures. Estimates of correlation dimensions of control EEG, interictal EEG and ictal EEG were calculated.
The values were demonstrated on topograms. The delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–30 Hz) and gamma
(30–40 Hz) components were obtained and considered as signals from the cortex. Corresponding surrogate data was produced.
Firstly, the influence of sampling parameters on the calculation was tested. The dimension estimates of the signals from the
frontal, temporal, parietal and occipital regions were computed and compared with the results of surrogate data. In the control
subjects, the estimates between the EEG and surrogate data did not differ (P > 0.05). The interictal EEG from the frontal region and occipital region, as well as its theta component from the frontal
region, and temporal region, showed obviously low dimensions (P < 0.01). The ictal EEG exhibited significantly low-dimension estimates across the scalp. All filtered rhythms from the temporal
region yielded lower results than those of the surrogate data (P < 0.01). The dimension estimates of the EEG and filtered components markedly changed when the neurological state varied.
For each neurological state, the dimension estimates were not uniform among the EEG and frequency components. The signal with
a different frequency range and in a different neurological state showed a different dimension estimate. Furthermore, the
theta and alpha components demonstrated the same estimates not only within each neurological state, but also among the different
states. These results indicate that the theta and alpha components may be caused by similar dynamic processes. We conclude
that the brain function underlying the ictal EEG has a simple mechanism. Several heterogeneous dynamic systems play important
roles in the generation of EEG.
Received: 10 December 1999 / Accepted in revised form: 8 May 2000 相似文献
19.
V. A. Ponomarev O. E. Gurskaya Yu. D. Kropotov L. V. Artjushkova A. Müller 《Human physiology》2010,36(2):123-131
The efficiencies of three clustering methods for independent components of 19-channel baseline EEG in location of pathological
cerebral activity sources were compared. The samples comprised 518 healthy subjects and 87 patients with postconcussion syndrome
after traumatic brain injury (TBI). Clustering of independent component topographies, the spatial coordinates of equivalent
dipole sources corresponding to independent component topographies, and locations of the maximums of the equivalent source
current density calculated by standardized low resolution electromagnetic tomography (sLORETA) were compared. A comparison
of the power spectra of independent components showed a significant increase in the EEG power in the Δ, θ, and α bands for
sources located in the frontal and temporal lobes of TBI patients compared to healthy subjects. The method of clustering of
independent component topographies proved to be the most sensitive of the methods compared. 相似文献
20.
V. Ya. Brodsky S. I. Rapoport T. K. Dubovaya N. D. Zvezdina V. I. Fateeva L. A. Malchenko 《Russian Journal of Developmental Biology》2010,41(2):77-81
Melatonin injected intraperitoneally into rat synchronizes the ultradian rhythm of protein synthesis after 100 min in primary
hepatocyte cultures isolated from this rat, which are studied after 1 or 2 days. The effective synchronization concentrations
of melatonin—0.01–0.02 μg per kg of rat weight—are three orders lower than melatonin doses used in clinical practice in human
treatment. 相似文献