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1.
Coherence at the frequency oftheta, alpha, and beta EEG rhythms was analyzed in 14 adults and 23 children of 7-8 years old while they performed cognitive tasks requiring an involvement of working memory (WM). We used the pair matching paradigm in which subjects had to match a pair of stimuli shown in succession in the central visual field. The pairs of verbal and visuo-spatial stimuli were mixed together and presented in a pseudo random order. Each pair was preceded by a warning signal that did not specify a modality of upcoming stimuli. We analyzed EEG segments recorded (i) in the rest condition, (ii) prior to the first (etalon) stimulus (maintenance of nonspecific voluntary attention), and (iii) prior to the second (test) stimulus (retention of information in WM). In the present study we focused on the regulatory functional components of WM, and therefore, the stimulus modality has not been taken into account. In adults, maintaining nonspecific voluntary attention was accompanied by an increase of the strength of theta-related functional coupling between medial areas of the frontal cortex and temporal cortical zones and by a strengthening of local beta-related functional connectivity in the anterior areas of the central cortex. In children, no such increase was found for theta-rhythm; for beta-rhythm the increase was limited to several short-range functional links. In adults, the retention of information in WM was accompanied by the growth in alpha coherence in distant fronto-parietal links, predominantly in the right hemisphere, while in children information retention was accompanied by the growth of theta-coherence in the inferio-temporal and parietal cortical regions. The results of the study point to a relative immaturity of the mechanisms of executive control of WM in children of 7-8 years old. 相似文献
2.
V. A. Ponomarev O. V. Kropotova Yu. D. Kropotov Yu. I. Polyakov 《Human physiology》2000,26(3):251-257
Evoked desynchronization and synchronization of EEG in θ (4–7.5 Hz), α (7.5–14 Hz) and β (14–20 Hz) ranges were recorded by
19 electrodes in healthy volunteer adolescents and those with attention deficit hyperactivity syndrome in the modified GO/NO-GO
test. Two stimuli (high and low tone) were presented in pairs with 1 s intervals inside the pair and 1.5 s intervals between
the pairs. Test subjects had to push the button in response to presentation of a pair of high tones and to ignore other stimulus
combinations. The components of evoked EEG synchronization in α-θ range that were revealed in the frontocentral and temporoparietal
brain regions in connection with inhibition of action (inhibition of movements and making a decision to cancel sensory-motor
task performance) were statistically significantly lower in subjects with attention deficit hyperactivity disorder compared
with that in healthy subjects. 相似文献
3.
E. A. Kostandov D. A. Farber E. A. Cheremushkin N. E. Petrenko M. L. Ashkinazi 《Human physiology》2011,37(5):519-525
The θ and α band EEG coherence during forming and testing sets to an emotionally negative facial expression (angry) was studied
in five- to six-year-old (n = 18) and 10- to 11-year-old (n = 25) children. Younger children displayed lower coherence values, especially in the right hemisphere, than older ones. Differences
in θ- and α band coherence in the cases of rigid and flexible sets to an angry face expression were also revealed. With relatively
rigid forms of cognitive activity, the EEG coherence values were lower. A correlation between the electrophysiological and
behavioral data was established. It supports the hypothesis that two functional brain integration systems, the corticohippocampal
and the frontothalamic ones, play a role in the processes of facial expression recognition and provide cognition flexibility. 相似文献
4.
L. A. Zhavoronkova A. V. Zharikova E. M. Kushnir A. A. Mikhalkova S. B. Kuptsova 《Human physiology》2011,37(6):688-699
Comprehensive EEG and stabilography investigation with separate and simultaneous performance of motor (voluntary postural
control) and cognitive (calculation) tasks has been performed in 20 healthy subjects (22 ± 0.7 years). Specific spatial and
frequency reactive changes have been found during motor task performance. These included an increase in coherence in the EEG
α band for distant derivation pairs in the right hemisphere, as well as in symmetric parietal-occipital areas in both hemispheres.
Cognitive task performance was accompanied by an increase in coherence for the slow bands (δ and θ) with a higher activation
in the left hemisphere and frontal cortex areas. In performing the dual task, one could observe activation of spatial and
frequency changes including both motor and cognitive tasks. In the dual tasks where both components were performed worse as
compared to the control, reactive reorganization of EEG coherence was less pronounced than during the performance of separate
tasks. A decrease in the coherence of the α1 band in the frontal areas appeared as a zone of “conflict of interest” or interference. In dual tasks with better performance
of each component as compared to the control, EEG coherence increased in each specific area, as well as in the areas of “conflict
of interests.” 相似文献
5.
A. A. Cherninskii I. G. Zima N. Ye. Makarchouk N. G. Piskorskaya S. A. Kryzhanovskii 《Neurophysiology》2009,41(1):63-70
We recorded EEG in adult volunteers in the course of perception of smells of plant essential oils under conditions of directed
attention. It was found that perception of olfactory information, even in the case of mild intensity of the smells inducing
no aversive effects, correlates with noticeable changes in the EEG characteristics mostly typical of the reaction of nonspecific
EEG activation induced by sensory stimulation and manifested in a decrease in the spectral power, SP, of low-frequency EEG
components (6–10 Hz)). In addition, the SP of relatively high-frequency EEG components (11–25 Hz) increased; this effect was
most pronounced in the occipital regions of the neocortex. Perception of the smells of essential oils was also accompanied
by increases in the coherence of EEG oscillations, most intense in the β2 range (20–25 Hz). Such modifications were maximum
in the left temporal/parietal region; this is interpreted as an indication of the special role of these cortical areas in
the processes of interaction between the neocortical part of the olfactory analyzer and the respective structures of other
analyzer systems. It is hypothesized that such interaction is necessary for the formation of a semantic image of the analyzed
stimuli.
Neirofiziologiya/Neurophysiology, Vol. 41, No. 1, pp. 70–78, January–February, 2009. 相似文献
6.
The coherence of the components of the EEG θ rhythm was analyzed in subjects performing a visual object classification task
under the conditions of uncertainty after a feedback. The functional coupling between cortical areas in the course of strategy
formation was demonstrated to be stronger than at the stage when the strategy had already been formed. The θ-related functional
connectivity were characterized by a specific topographic pattern: they converged to the foci located in the polar frontal
cortex and reflect the interaction of these frontal areas with the anterior associative and temporal cortices of the left
hemisphere, as well the parietal and occipital areas of both hemispheres. The frequency and topographic characteristics of
the functional cortical links suggest that they reflect the functioning of a distributed neural network through which the
limbic structures and the controlling frontal cortical structures interact in the process of cognitive strategy formation. 相似文献
7.
Electroencephalograms (EEGs) were recorded in 19 standard derivations in 88 healthy subjects (students) in the state of rest
with eyes open and during memorization (learning) of verbal bilingual semantic pairs (the Latin and Russian languages) and
retrieval of information from memory (control). The estimates of EEG coherence in these states were compared for the following
frequency bands: θ (4–7 Hz), α1 (7–10 Hz), α2 (10–13 Hz), β1 (13–18 Hz), β2 (18–30 Hz), and γ (30–40 Hz). Compared to the state of rest, the decrease in coherence in the pairs of derivations from the
frontal and central cortical areas in all EEG frequency bands was the most pronounced for memorization, and the increase in
coherence in the interhemispheric derivation pairs of the parietal-occipital region in most of the frequency bands was the
most pronounced for retrieval. In addition, in the pairs formed by derivations from the parietal-occipital region with derivations
from the frontal and central regions, retrieval is also characterized by an increase in coherence in the β2 and γ bands along with its decrease in the low-frequency ranges. The dynamics of EEG coherence, when comparing the states
of memorization and retrieval, is more statistically significant in the interhemispheric and cross-hemispheric pairs of derivations
than in the intrahemispheric pairs. The revealed topographic specificity of the dynamics of EEG coherence owing to the change
of state is considered in terms of the notion on cognitive-specific forms of sustained goal-directed mental attention. 相似文献
8.
I. N. Konareva 《Neurophysiology》2012,43(6):459-467
In a group including 65 adults of both sexes, we examined correlations of the internal/external personality type (locus of
psychological control diagnosed by the Rotter questionnaire) with parameters of the EEG frequency components (rhythms). Multichannel
recording of ongoing EEG was carried out in the resting state; leads were located according to the 10-20 system. Despite natural
high interindividual variability, the subgroup of internals was, in general, characterized by higher spectral powers (SPs)
of the δ, θ, α, and β1 rhythms and a lower SPs of β2 and γ oscillations recorded in the resting state with the eyes closed.
In internals, the modal frequencies of practically all EEG ranges were, on average, somewhat lower. In this subgroup, reaction
of EEG activation related to opening of the eyes was stronger, while the interhemisphere asymmetry was weaker. 相似文献
9.
Modality-specific and supramodal EEG components that are related to the reorientation of involuntary anticipatory attention
from the internal to the external type were studied by comparing the unblocking of the visual and acoustic channels. EEG recording
was performed while subjects were at rest with their eyes open, with their eyes closed, or with their eyes closed while using
noise-protective earplugs. The means of both the EEG power in each of the derivations and EEG coherence in each of the derivation
pairs were calculated for every subject and for each of the states. The estimations have been done for the Δ, θ, α1, α2, β1, β2, and γ frequency bands. The obtained data proved the hypothesis on the manifestation of both modality-specific and supramodal
components in the brain mechanisms of involuntary anticipatory attention. These results are of interest for discussion on
the degree of similarity and distinction between the systemic supports of the brain mechanisms of visual and auditory attention. 相似文献
10.
Parameters of cortical interactions depending on the level of creative achievements were studied in 40 right-handed subjects
(22 men and 18 women). EEG was recorded at rest and during performance of a verbal creativity task (the Cognitive Synthesis
test). The subjects were divided (by the median split) into groups with high and low originality scores (OSs). EEG coherence
was computed within a range of frequencies from 4 to 30 Hz. The total values of coherence were determined separately for intra-
and interhemispheric coherent connections using each of 16 electrode sites. Unlike subjects with a low OS, those with a high
OS values were characterized by a decrease in the interhemispheric coherence of the θ1,2-rhythm bioelectric potentials, which was especially pronounced in frontal cortical regions, and by an increased β1-rhythm interhemispheric coherence in the occipital and temporal-parietal brain regions. The results are discussed in the
context of right- and left-hemisphere contributions into the top-down and bottom-up regulation mechanisms during creative
thinking. 相似文献
11.
I. N. Konareva 《Neurophysiology》2005,37(5-6):388-395
We studied changes in the frequency pattern of EEG related to a single session of biological feedback by the EEG characteristics
(neurofeedback, NFB) directed toward an increase in the ratio of α/θ spectral powers (SPs) (an experimental group; 30 subjects)
and to a session of the supposedly indifferent acoustic influence (listening to a musical background; 30 persons). A standard
technique of EEG recording was used; the loudness of white noise overlapping the musical background served as an NFB signal.
EEG was recorded from the C3 and C4 leads. Within the examined experimental group, an NFB session elicited a trend toward
statistically insignificant decreases in the SPs of δ, α, and β rhythms and increases in the SPs of θ and γ EEG components.
Listening to a supposedly neutral musical background by the control group, with no attempts at self-control of the SPs of
EEG rhythms, was followed by rather clear unidirectional (partially significant) decreases in the SPs of θ, α, β, and γ components;
the δ activity in the left hemisphere decreased, while in the right hemisphere it increased. In general, results of the single
NFB session were characterized by a high interindividual variability, which can be related mostly to the specificities of
psychophysiological characteristics of the personality of the tested subject.
Neirofiziologiya/Neurophysiology, Vol. 37, Nos. 5/6, pp. 443–451, September–December, 2005. 相似文献
12.
Functional connectivity between the prefrontal cortex and the temporal and temporo-parieto-occipital cortices in the process of preparing for the recognition of fragmented images were analyzed in adults (n = 26) and seven- to eight-year-old children (n = 20).The evaluations of the imaginary part of the complex-valued coherency for the EEG alpha-rhythm (Jα) were used as an index for the strength of cortico-cortical interactions. The Jα value was analyzed in the following three experimental conditions corresponding to different stages of readiness for visual recognition: (1) nonspecific attention holding in the period preceding a warning stimulus (S1); (2) focused attention in the interval preceding a not-yet-recognized target stimulus (S2) and (3) pretuning preceding a recognized stimulus (S3). Adult subjects tended towards a growing level of functional connectivity in α-rhythm in progressing from attention holding to focused attention preceding the emergence of a target stimulus, but children, on the contrary, demonstrated a decreasing trend. Comparing the Jα values in the subgroups of adults and children who showed the highest recognition scores in the solution of cognitive tasks helped reveal age-specific patterns in the rearrangements of cortico-cortical functional connectivity in α-rhythm in the left and right hemispheres at different stages of readiness for recognizing incomplete images. In adults, the maximal Jα values were found in the left hemisphere in the interval preceding the recognition of a target image. At this stage of pretuning, the Jα values at the leads in the left hemisphere in adults significantly exceeded those in children. The Jα values for the right hemisphere in adults were maximal during focused prestimulus attention when the image was not yet recognized and these values were significantly higher than in children under the same experimental conditions. Children showed maximal Jα values in both hemispheres during nonspecific attention. The specifics of functional connectivity observed between the prefrontal, temporal and temporo-parieto-occipital cortices in seven- to eight-year-old children during functional pretuning to the recognition of fragmented images are considered to reflect the relative immaturity of neurophysiological mechanisms underlying the voluntary attention and working memory in children of this age group. 相似文献
13.
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
14.
Independent component analysis (ICA) of 19-channel background EEG was performed in 111 patients with the early signs of depressive
disorders and in 526 healthy subjects. The power spectra of the independent components were compared in the depressive patients
and in healthy subjects at the eyes closed and eyes opened states. Statistically significant differences between the groups were detected in three frequency bands: θ (4–7.5 Hz), α
(7.5–14 Hz), and β (14–20 Hz). Increased θ and α activities in parietal and occipital derivations of depressive patients may
have been caused by a reduced cortical activity in the projection of these derivation. Diffuse enhancement of the β activity
may be correlated with anxiety symptoms that are pronounced in the clinical picture of depressive disorders at early stages
of the disease. ICA used to compare quantitative EEG parameters in different groups of patients and in healthy persons makes
it possible to localize the differences more accurately than the traditional analysis of EEG spectra. 相似文献
15.
R. I. Machinskaya 《Human physiology》2006,32(1):20-29
A particular role was demonstrated for functional maturation of the frontothalamic system (FTS) of the brain in forming the cerebral organization of selective voluntary attention in ontogeny. Analysis of the coherence of the rhythmic components of the EEG α range in adults and seven-to eight-and nine-to ten-year-old children showed that, if the functional state of the control structures corresponds to the age, the formation of the neurophysiological mechanisms selectively modulating cortical activity and supporting selective tuning of the cerebral structures to the cognitive task is completed by the age of seven or eight years. Unlike adults, children demonstrated no interhemispheric features of the intercenter integration of cortical zones in the prestimulus period of voluntary attention. Children with a functionally immature FTS lacked selective specific integration of cortical zones in the pretuning period. The deficit of selective modulation of cortical activity in children with a functionally immature FTS is considered as the neurophysiological factor that delays the formation of voluntary attention and voluntary control of activity and, finally, leads to learning difficulties. 相似文献
16.
L. A. Zhavoronkova O. A. Maksakova N. Ya. Smirnova O. A. Krotkova V. L. Naidin 《Human physiology》2001,27(2):133-142
Dynamic clinical and EEG examinations (78 observations) were carried out in 17 patients suffering from severe craniocerebral injury during the course of their rehabilitation. Successful recovery of functions to the point of social and family readaptation was reached in 61% of patients (group I), and in 39% of patients the results were poor (group II). The complex of EEG coherence parameters (six rhythmic bands, mean coherence levels for 26 intrahemispheric and 8 interhemispheric derivation pairs, and the asymmetry coefficient of the EEG coherence) was analyzed in patients in comparison with normal values (20 right-handers). The rehabilitation was most efficient in cases when a certain dynamic sequence of patterns of interhemispheric relations of the EEG coherence was observed. First, a stable formation of right-hemispheric dominance was observed (most expressed in the centrofrontal areas in the range). This asymmetry pattern was phenomenologically associated with the recovery of the emotional sphere and positive dynamics in the motor and autonomic spheres. Later on, formation of the left-hemispheric dominance of the EEG coherence was observed (in the frontotemporal areas in the – ranges. This pattern was associated with complication of the cognitive functions. In the most severe forms of brain damage, the rehabilitation process was accompanied by changes in the interhemispheric EEG coherence with the elements of stealing from one of the hemispheres, which was correlated with clinical dynamics. Different types of the dynamics of reactive changes in the EEG coherence were revealed in patients of the two groups: successive formation of a generalized and then local modally specific reaction to afferent stimuli was observed in group I, while the generalized type of reactivity persisted in group II until the end of rehabilitation. It is suggested that the different sequence of formation of the interhemispheric EEG coherence reflects the involvement of different brain regulation systems in different orders into the integrative activity, i.e., some specific features of the rehabilitation process. 相似文献
17.
I. I. Korobeinikova 《Human physiology》2011,37(5):537-544
Students (46 young men) were asked to memorize and reproduce the order and location (on a computer monitor) of signals. Two
groups of subjects were formed according to how accurately they reproduced the true location and order of the signals. Subjects
of the first group, in contrast to the second group, reproduced the signal location and order at a high accuracy and with
few mistakes even in the first trials. EEGs were recorded prior to the test, during memorizing, and after completion of the
task. In the initial state and after completion of the task, the two groups did not differ in the EEG θ-rhythm. During memorizing
the signal sequence, an increase in the coefficients of coherence was recorded in the EEG θ band of the right brain hemisphere
of the first-group of students; this was not characteristic of the second group. Three systems of connection with the foci
of activity were determined in the right occipital, central, and frontal cortical areas, where the coherence of the EEG θ
band was significantly higher during memorizing in the students that had exhibited a high accuracy of signal reproduction.
Since the right hemisphere deals mainly with the perception of visual spatial information and it is more active in processing
nonverbal and stereotyped signals, we have suggested that the students of two groups employed different strategies in solving
the task during memorizing. 相似文献
18.
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
19.
I. N. Konareva 《Neurophysiology》2011,42(6):434-445
In a group of 118 adults of both sexes, we studied modulation of the low-frequency EEG components (δ and θ rhythms) under
conditions of an activation reaction resulting from opening of the eyes. Typical changes of the α rhythm (considerable depression
in a great majority of the tested subjects) was accompanied by diverse, in their direction, shifts of the spectral power (SP)
of the δ and θ components in different subjects. The δ rhythm power increased upon the reaction of activation in 79 subjects
and decreased in 29 subjects, while changes in this index in different hemispheres were of opposite directions in 10 persons.
According to the reactivity of the θ rhythm, the respective subgroups included 36, 75, and 7 subjects. Values of the differential
coefficients of reactivity (DCR) for the δ and θ rhythms demonstrated significant positive correlation (r = 0.616 and 0.603
for the left and right hemispheres, respectively). Indices of reactivity of the α and θ rhythms also correlated but less closely
(r about 0.3). At the same time, there was practically no correlation between the DCR values of the α and δ rhythms. Within
the entire studied group, we found significant negative correlations between the DCRs of the δ and θ activity with the estimates
of some psychological characteristics of the subjects (levels of extroversion, psychoticism, ergicity, plasticity, dominance,
and a few others) measured using the questionnaires RTS (Strelau), EPQ (Eysenck), OST (Rusalov), and 16 PF (Kettel). We also
found positive correlations with the levels of normativity of behavior and development of imagination. At a rather high significance
of such correlations, coefficients of the latter were, as a rule, relatively low (usually less than 0.2). Results of dispersion
analysis showed that significant or close to significant intergroup differences of the mean values of estimates of psychological
characteristics diagnosed according to the above-mentioned questionnaires were typical of the subgroups of subjects with increases
and decreases in the SPs of the δ and θ rhythms or with opposite changes of these indices in the hemispheres. Probable mechanisms
of modulation of the low-frequency EEG components under conditions of the activation reaction and correlations of such changes
with psychological peculiarities of the personality are discussed. 相似文献
20.
We studied changes in the power spectra of EEG in the course of sessions of feedback by EEG characteristics (neurofeedback
sessions) and estimated the effects of neurofeedback on psychological and EEG correlates of voluntary attention. Indices of
the latter were estimated using Bourdon’s test (a correcture test) and Schulte’s tables. Twenty-nine reasonably healthy 10-to
13-year-old children took part in the study; they were divided into two groups, an experimental group (n = 12) and a control group (n = 15). The results obtained support the statement on noticeable changes in the functional state of the brain both immediately
in the course of a neurofeedback session and after a course of such trainings. Changes in the ratios of the spectral powers
of the beta1
vs theta rhythms and the low-frequency beta vs theta rhythms were found in EEG recorded from the sensorimotor zone of the right hemisphere (C4). The observed changes in
the spectral characteristics of EEG induced by the course of neurofeedback sessions were accompanied by the improvement of
a few indices of voluntary attention.
Neirofiziologiya/Neurophysiology, Vol. 38, Nos. 5/6, pp. 458–465, September–December, 2006. 相似文献