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1.
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
2.
We studied changes in the amplitudes of event-related EEG potentials (ERPs) and power spectra of background EEG in the course
of a series of EEG-feedback sessions directed toward an increase in the ratio of powers of the α vs θ rhythms. The examined group included 70 volunteers divided into an experimental group (n = 37) and a control group (n = 33). The intensity of acoustic white noise overlapping the musical background served as a feedback signal; it became lower
with increase in the above ratio, while in the control group it remained constant. The EEG potentials were recorded from C3
and C4 leads. The ERPs were recorded within a paradigm of measuring time intervals. Within a series of EEG-feedback sessions,
the α/θ ratio decreased somewhat both in the control and experimental groups, but in subjects of the latter group this decrease
was less significant, and the mean intragroup index became significantly greater than the respective value in the control
group after the end of the third session. The EEG-feedback sessions also resulted in significant increases in the amplitudes
of early components of the readiness potential in both hemispheres and in the amplitude of the contingent negative variation
in the right hemisphere. We conclude that, in most healthy subjects, at least three sessions of α/θ training are necessary
to form an effective series providing considerable changes in the pattern of EEG potentials.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 1, pp. 88–98, January–February, 2007. 相似文献
3.
E. V. Evstaf’eva O. A. Zalata E. V. Repinskaya I. A. Evstaf’eva M. G. Shchegoleva S. L. Tymchenko N. M. Ovsyannikova 《Neurophysiology》2006,38(2):142-148
In 18-to 19-year-old students, the content of a number of microelements, as well as of calcium, in biologically stable tissues
(hair samples) was measured using X-ray fluorescent analysis. In the tested persons, we observed a certain deficit of main
elements (calcium, copper, and zinc), while in some persons the levels of toxic lead and strontium were exceeded. Correlation
analysis of the parameters of EEG potentials (current EEG and evoked and event-related potentials, EPs and ERPs, respectively)
showed the existence of a few significant (or close to those) correlations of the spectral powers of some rhythms and derivatives
of a few indices of the background EEG and more numerous cases of correlations of the parameters of EPs and ERPs (latencies
and amplitudes) with the contents of the studied elements. The physiological importance of metals, according to the number
of characteristics of EEG potentials that correlate with their contents, can be arranged in descending order as follows: As,
Zn > Ca > Cd > Pb > Sr. None of the studied parameters of EEG phenomena correlated with the level of copper. The strength
of correlations varied from weak to mild (0.29 < R < 0.50). The densest correlations were observed for the concentrations of toxic lead and cadmium. With respect to the characteristics
of ERPs, some of the elements under study demonstrated synergism (e.g., lead and arsenic), while others were in an antagonistic
relation (cadmium and calcium).
Neirofiziologiya/Neurophysiology, Vol. 38, No. 2, pp. 167–174, March–April, 2006. 相似文献
4.
Measures of event-related band power such as event-related desynchronization (ERD) are conventionally analyzed within fixed
frequency bands, although it is known that EEG frequency varies as a function of a variety of factors. The question of how
to determine these frequency bands for ERD analyses is discussed and a new method is proposed. The rationale of this new method
is to adjust the frequency bands to the individual alpha frequency (IAF) for each subject and to determine the bandwidth for
the alpha and theta bands as a percentage of IAF. As an example, if IAF equals 12 Hz, the widths of the alpha and theta bands
are larger as compared to a subject with an IAF of, e.g., only 8 Hz. The results of an oddball paradigm show that the proposed
method is superior to methods that are based on fixed frequencies and fixed bandwidths.
Received: 22 July 1997 / Accepted in revised form: 22 April 1998 相似文献
5.
D. J. Davidson 《Neurophysiology》2009,41(1):71-79
In electro/psychophysiological experiments, linear mixed-effect modeling is an effective statistical technique for data repeatedly
observed from the same experimental participants or stimulus items. This review describes the application of mixed-effect
modeling to functional responses, in particular those observed in event-related EEG or MEG experiments, using a discrete wavelet
transform. The technique is illustrated with a design with several covariates, and procedures for generating posterior samples
and computing a Bayesian false discovery rate are described.
Neirofiziologiya/Neurophysiology, Vol. 41, No. 1, pp. 79–87, January–February, 2009. 相似文献
6.
Ferreira AG Scherer EB da Cunha MJ Machado FR Cunha AA Graeff JS Netto CA Wyse AT 《Neurochemical research》2011,36(12):2306-2315
This study investigated whether physical exercise would reverse proline-induced performance deficits in water maze tasks,
as well as its effects on brain-derived neurotrophic factor (BDNF) immunocontent and brain acetylcholinesterase (AChE) activity
in Wistar rats. Proline administration followed partial time (6th–29th day of life) or full time (6th–60th day of life) protocols. Treadmill exercise was performed from 30th to 60th day of life, when behavioral testing
was started. After that, animals were sacrificed for BDNF and AChE determination. Results show that proline impairs cognitive
performance, decreases BDNF in cerebral cortex and hippocampus and increases AChE activity in hippocampus. All reported effects
were prevented by exercise. These results suggest that cognitive, spatial learning/memory, deficits caused by hyperprolinemia
may be associated, at least in part, to the decrease in BDNF levels and to the increase in AChE activity, as well as support
the role of physical exercise as a potential neuroprotective strategy. 相似文献
7.
Background
Motor imagery training is a promising rehabilitation strategy for stroke patients. However, few studies had focused on the neural mechanisms in time course of its cognitive process. This study investigated the cognitive alterations after left hemispheric ischemic stroke during motor imagery task.Methodology/Principal Findings
Eleven patients with ischemic stroke in left hemisphere and eleven age-matched control subjects participated in mental rotation task (MRT) of hand pictures. Behavior performance, event-related potential (ERP) and event-related (de)synchronization (ERD/ERS) in beta band were analyzed to investigate the cortical activation. We found that: (1) The response time increased with orientation angles in both groups, called “angle effect”, however, stoke patients’ responses were impaired with significantly longer response time and lower accuracy rate; (2) In early visual perceptual cognitive process, stroke patients showed hypo-activations in frontal and central brain areas in aspects of both P200 and ERD; (3) During mental rotation process, P300 amplitude in control subjects decreased while angle increased, called “amplitude modulation effect”, which was not observed in stroke patients. Spatially, patients showed significant lateralization of P300 with activation only in contralesional (right) parietal cortex while control subjects showed P300 in both parietal lobes. Stroke patients also showed an overall cortical hypo-activation of ERD during this sub-stage; (4) In the response sub-stage, control subjects showed higher ERD values with more activated cortical areas particularly in the right hemisphere while angle increased, named “angle effect”, which was not observed in stroke patients. In addition, stroke patients showed significant lower ERD for affected hand (right) response than that for unaffected hand.Conclusions/Significance
Cortical activation was altered differently in each cognitive sub-stage of motor imagery after left hemispheric ischemic stroke. These results will help to understand the underlying neural mechanisms of mental rotation following stroke and may shed light on rehabilitation based on motor imagery training. 相似文献8.
While neuronal desynchronization in the mu (≈10Hz) and beta (≈20Hz) frequency bands has long been known to be an EEG index of sensorimotor activity, this method has rarely been employed to study auditory perception. In the present study, we measured mu and beta event-related desynchronisation (ERD) while participants were asked to listen to vocal and triangle-wave melodies and to sing them back. Results showed that mu and beta ERD began earlier and were stronger when listening to vocal compared to non-vocal melodies. Interestingly, this humanness effect was stronger for less accurate singers. These results show that voice perception favors an early involvement of motor representations. 相似文献
9.
I. N. Konareva 《Neurophysiology》2011,42(5):354-361
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. 相似文献
10.
A Generalized Framework for Quantifying the Dynamics of EEG Event-Related Desynchronization
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Brains were built by evolution to react swiftly to environmental challenges. Thus, sensory stimuli must be processed ad hoc, i.e., independent—to a large extent—from the momentary brain state incidentally prevailing during stimulus occurrence. Accordingly, computational neuroscience strives to model the robust processing of stimuli in the presence of dynamical cortical states. A pivotal feature of ongoing brain activity is the regional predominance of EEG eigenrhythms, such as the occipital alpha or the pericentral mu rhythm, both peaking spectrally at 10 Hz. Here, we establish a novel generalized concept to measure event-related desynchronization (ERD), which allows one to model neural oscillatory dynamics also in the presence of dynamical cortical states. Specifically, we demonstrate that a somatosensory stimulus causes a stereotypic sequence of first an ERD and then an ensuing amplitude overshoot (event-related synchronization), which at a dynamical cortical state becomes evident only if the natural relaxation dynamics of unperturbed EEG rhythms is utilized as reference dynamics. Moreover, this computational approach also encompasses the more general notion of a “conditional ERD,” through which candidate explanatory variables can be scrutinized with regard to their possible impact on a particular oscillatory dynamics under study. Thus, the generalized ERD represents a powerful novel analysis tool for extending our understanding of inter-trial variability of evoked responses and therefore the robust processing of environmental stimuli. 相似文献
11.
《Electronic Notes in Theoretical Computer Science》1993,88(1):32-41
Our laboratory has repeatedly found a left < right auditory P300 temporal lobe topographic asymmetry in right-handed, medicated schizophrenics. To determine whether this asymmetry was attributable to the effects of antipsychotic medications, we collected auditory “odd-ball” P300 event-related potentials from 14 right-handed, unmediated schizophrenics (withdrawn from medication for an average of 21 days) and 14 right-handed, normal controls. Analysis of normalized P300 amplitudes showed a statistically significant difference in the voltage distributions between groups (a group by temporal electrode site interaction) that was consistent with a left < right temporal voltage asymmetry in schizophrenics but not in the normal controls. We conclude that P300 topographic asymmetries are present in unmedicated schizophrenics. These data are compatible with the growing body of data suggsting left temporal lobe structural abnormalities in schizophrenia. 相似文献
12.
We estimated the efficacy of using the technique of feedback (FB) by EEG characteristics (EEG-FB, neurotherapy) with the aim
of reducing increased anxiety levels in healthy 10- to 14-year-old children. The anxiety level was estimated using the Prikhojan
anxiety test, the Spielberger–Khanin questionnaire, and the House–Tree–Person projective drawing technique. Positive effects
of series of neurotherapy sessions were obvious. After training was completed, we observed significant increases in the ratios
of the amplitudes of alpha and theta rhythms, semsorimotor and theta rhythms, as well as of the modal frequency of the EEG
alpha rhythm in tested persons of the experimental group (n = 7). In the control group (n = 10), changes in these values did not reach the significance level. In the experimental group of tested persons subjected
to EEG-FB sessions, the anxiety level decreased appreciably; in addition, the indices “feeling of inferiority” and “frustration”
decreased significantly. In the control group, alterations of these psychological indices were not unidirectional. Therefore,
modifications of the EEG pattern, which occurred in the course of training and were accompanied by a decrease in the anxiety
level in the experimental group, can be indicative of the expediency of EEG-FB for the reduction of high anxiety levels in
children and teenagers. 相似文献
13.
《Electronic Notes in Theoretical Computer Science》1997,104(3):199-206
To investigate the activity of cortical regions in the control of movement, we studied event-related desynchronization/synchronization (ERD/ERS), event-related coherence (ERC), and phase coherence in 29-channel EEGs from 9 subjects performing self-paced movements of the right index finger. Movement preparation and execution produced ERD over the sensorimotor areas at 10 Hz and 20 Hz, followed by ERS. ERD corresponded spatiotemporally to an increase in coherence over the frontocentral areas. For both frequency bands, ERD began over the left sensorimotor areas and became bilateral at the time of movement onset. The coherence increase with frontal areas began in the left central areas and became symmetrical after EMG onset. The ERD and coherence increase was longer at 10 Hz than at 20 Hz. Phase coherence at 10 Hz showed a lead of anterior regions to posterior regions throughout the time period, and at 20 Hz showed a tendency toward zero phase delay corresponding with the movement. EEG desynchronization parallels functional coupling over sensorimotor and frontal areas. Event-related coherence and phase coherence findings implicate the frontal lobes in control of movement planning and execution. The involvement of different frequency bands with different timings may represent parallel changes in the cortical network. 相似文献
14.
Correlations between indices of P300 EEG potential,cognitive tests,and variational pulsometry in Parkinsonian patients 总被引:1,自引:1,他引:0
The parameters of an event-related EEG potential (ERP), P300 wave, are now extensively used as objective neurophysiological
indices of the state of cognitive functions. At the same time, information on the effects of the autonomic nervous system
on the parameters of P300 is limited. In Parkinson’s disease clinics, in addition to the leading motor disorders, more or
less clear psychoemotional, cognitive, and autonomic (in particular cardiovascular) impairments are usually observed. This
allows one to study the dependence between the cardiovascular dysfunction and intensity of cognitive disorders in Parkinsonian
patients. In our study on this contingent, we analyzed correlations between the parameters of P300 potential, indices of the
state of the cognitive sphere (determined using a questionnaire, Mini Mental State Examination, MMSE, and a Luriya’s test),
and indices of variational pulsometry. Thirty-five Parkinsonian patients (49 to 74 years, severity of disease 1.5 to 3.0 by
the international classification) were examined. We found a negative influence of excessive sympathetic tonus in cardiovascular
control on the state of cognitive functions. The latency of P300 potential was longer in patients with greater intensities
of sympathetic influences on the cardiovascular system. The coefficients of correlation of the latency of P300 with the amplitude
of mode of R-R intervals (AMo), index of tension in the regulatory systems by Baevskii (IT), and index of autonomic balance
by Baevskii (IAB) were 0.52 (P < 0.01), 0.36 (P < 0.05), and 0.37 (P < 0.05), respectively. The above autonomic indices demonstrated significant negative correlations with the volume of short-term
memory measured by Luriya’s test. The P300 latency, in turn, showed negative correlations with the memory volume estimated
by the MMSE scale and Luriya’s test. With increase in the age of patients, the degree of the above-mentioned correlations
between the P300 latency, memory volume (by Luriya’s test), and parameters of variational pulsometry increased. Our data emphasize
the expedience of “routine” studies of the balance of sympathetic and parasympathetic control in pathological states accompanied
by clear or subclinical cognitive disorders. Early recognition of cardiovascular dysfunction and its corresponding therapeutic
correction should improve the state of brain functions and quality of life in patients suffering from neurodegenerative diseases,
in particular from Parkinson’s disease.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 1, pp. 43–52, January–February, 2008. 相似文献
15.
Wavelet entropy in event-related potentials: a new method shows ordering of EEG oscillations 总被引:3,自引:0,他引:3
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 相似文献
16.
Prospective memory (PM) refers to memory for future intentions. Difference due to memory (Dm effect) is the difference in
neural activity related to stimuli that were subsequently remembered or forgotten. Using event-related potentials (ERPs),
the present study investigated the Dm effect for PM using a subsequent task-switching paradigm. The results showed that a
Dm effect of ERP P150 was more positive-going for later PM hit trials than for later PM forgotten trials during 100–200 ms.
This Dm effect may reflect the process for the production of future intention or the process for attention. Consistent with
previously reported Dm effects of other types of memory, we found that the fbN2 (250–280 ms) and late positivity component
(400–700 ms) were stronger in later PM hit trials than in forgotten trials. The fbN2 was evoked by Chinese characters. The
late positivity component was related to the precise encoding process. In conclusion, because of the early P150, PM encoding
appears to be somewhat different from previously identified Dm effects. However, further research is needed. Our findings
reveal that Dm effects of PM share similar characteristics with known Dm effects of other types of episodic memory after the
very early stage of neural processing. 相似文献
17.
We compared the alpha band EEG depression (event-related desynchnization, ERD) level in two tasks, involving activation of different attentional processes: visual search for a deviant relevant stimulus among many similar ones and visual oddball. Control data for the visual search task consisted of simple viewing of several stimuli being of the same shape as the relevant stimulus in the search trials. Gaze position was verified by eye tracking method. We interpreted alpha band ERD as a correlate of activation of attentional processes. Fixating the target in visual search task caused a significantly larger ERD than fixating the same stimuli in control trials over all leads. We suppose this to be related with task and visual environment complexities. The frontal ERD domination may indicate attentional control over voluntary movements execution (top-down attention). The caudal ERD may be related with updating of visual information as a result of search process (bottom-up attention). Both relevant and irrelevant stimuli in the oddball task also induced alpha band ERD, but it was larger in response to relevant one and reached maximum level over occipital leads. Domination of caudal ERD in oddball task is supposed to indicate bottom-up attention processes. 相似文献
18.
Reflection of Anxiety in the Characteristics of Evoked EEG Potentials in 10- to 11-Year-Old Children
We studied the peculiarities of the amplitude/time parameters of evoked EEG potentials (EPs) and event-related potentials
(ERPs) in 10- to 11-year-old children characterized by low and high anxiety levels. The latter levels were estimated using
the scale of the manifest anxiety test of Prikhozhan and projective techniques (“House–Tree–Person,” HTP, and the Lüscher
color test). For children with a high anxiety level, the amplitudes of the following EP components and ERPs were lower than
those in low-anxiety children of the same age: P1 (predominantly in the occipital region of the left hemisphere), P2 (in the
right occipital region), and Р300 wave (in different loci of both hemispheres). In high-anxiety children, we also more frequently
observed increased amplitudes of the N2 component in the left parietal and right occipital regions. High-anxiety individuals
were characterized by longer latencies of component P1 (mostly in the right frontal and left central regions) and, at the
same time, shorter latencies of component N1 (in the parietal and occipital regions of the left hemisphere and also in the
right temporal region). Thus, we found that the amplitude/time characteristics of a few EP components and ERPs in children
with high anxiety levels differ statistically significantly from the parameters of corresponding EPs/ERPs in individuals of
the same age but with low anxiety levels. 相似文献
19.
Yasuo Yagi Kerry L. Coburn Kristi M. Estes James E. Arruda 《European journal of applied physiology and occupational physiology》1999,80(5):402-408
Visual and auditory reaction times (RTs) have been reported to decrease during moderate aerobic exercise, and this has been interpreted as reflecting an exercise-induced activation (EIA) of cognitive information processing. In the present study we examined changes in several independent measures of information processing (RT, accuracy, P300 latency and amplitude) during exercise, and their relationship to visual or auditory modalities and to gender. P300 latencies offer independent measures of cognitive speed that are unrelated to motor output, and P300 amplitudes have been used as measures of attentional allocation. Twenty-four healthy college students [mean (SD) age 20 (2) years] performed auditory and visual "oddball" tasks during resting baseline, aerobic exercise, and recovery periods. Consistent with previous studies, both visual and auditory RTs during exercise were significantly shortened compared to control and recovery periods (which did not differ from each other). We now report that, paralleling the RT changes, auditory and visual P300 latencies decreased during exercise, indicating the occurrence of faster cognitive information processing in both sensory modalities. However, both auditory and visual P300 amplitudes decreased during exercise, suggesting diminished attentional resource allocation. In addition, error rates increased during exercise. Taken together, these results suggest that the enhancement of cognitive information processing speed during moderate aerobic exercise, although operating across genders and sensory modalities, is not a global facilitation of cognition, but is accompanied by decreased attention and increased errors. 相似文献
20.
Makeig S Delorme A Westerfield M Jung TP Townsend J Courchesne E Sejnowski TJ 《PLoS biology》2004,2(6):e176
Scalp-recorded electroencephalographic (EEG) signals produced by partial synchronization of cortical field activity mix locally synchronous electrical activities of many cortical areas. Analysis of event-related EEG signals typically assumes that poststimulus potentials emerge out of a flat baseline. Signals associated with a particular type of cognitive event are then assessed by averaging data from each scalp channel across trials, producing averaged event-related potentials (ERPs). ERP averaging, however, filters out much of the information about cortical dynamics available in the unaveraged data trials. Here, we studied the dynamics of cortical electrical activity while subjects detected and manually responded to visual targets, viewing signals retained in ERP averages not as responses of an otherwise silent system but as resulting from event-related alterations in ongoing EEG processes. We applied infomax independent component analysis to parse the dynamics of the unaveraged 31-channel EEG signals into maximally independent processes, then clustered the resulting processes across subjects by similarities in their scalp maps and activity power spectra, identifying nine classes of EEG processes with distinct spatial distributions and event-related dynamics. Coupled two-cycle postmotor theta bursts followed button presses in frontal midline and somatomotor clusters, while the broad postmotor "P300" positivity summed distinct contributions from several classes of frontal, parietal, and occipital processes. The observed event-related changes in local field activities, within and between cortical areas, may serve to modulate the strength of spike-based communication between cortical areas to update attention, expectancy, memory, and motor preparation during and after target recognition and speeded responding. 相似文献