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1.
Changes in face expression recognition and EEG synchronization arising from additional load on working memory were studied in healthy adults. Two types of additional task--semantic and visuospatial--were used to load working memory in an experiment with a visual set, formed to facial stimuli. During perception of new facial stimuli, both these types of additional task caused an increase of erroneous face expression recognitions in the form of assimilative illusions. Alpha-band (8-10 Hz) EEG synchronization analysis revealed that additional memory load causes a decrease of frontal attention system input in set-forming and set-shifting. As for theta-band (4-7 Hz) synchronization, it changed ambiguously at additional memory load--in right fronto-temporal region coherence function decreased; other coherence connections, especially intra-hemispheric and in the left hemisphere, increased. At issue is the crucial role of fronto-thalamic and cortico-hippocampal systems in plasticity of visual sets formed to facial expressions. 相似文献
2.
Kostandov EA Cheremushkin EA Iakovenko IA Ashkinazi ML 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2010,96(11):1075-1087
Influence of additional working memory load on emotional face recognition was studied in healthy adults. Visual set to emotional face expression was experimentally formed, and two types of additional task--visual-spatial or semantic--were embedded in the experiment. Additional task caused less plastic set, i.e., a slower set-shifting. This effect displayed itself in an increase of erroneous facial expression perceptions. The character of these erroneous perceptions (assimilative or contrast or visual illusions) depended on the type of the additional task. Pre-stimulus EEG coherence across experimental trials in theta (4-7), low alpha (8-10 Hz) and beta (14--20) bands was analysed. Data of low-alpha and beta-coherence supported the hypothesis that increased memory load caused less involvement of frontal lobes in selective attention mechanisms that are associated with set-forming. This results in a slower set-shifting. Increased memory load also led to a growth of theta-band coherence in the left hemisphere and its decrease in the right hemisphere. The account of theta-coherence decrease in the right hemisphere between prefrontal and temporal areas for a slower set-shifting is discussed. 相似文献
3.
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
4.
Kostandov EA Cheremushkin EA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2011,61(1):35-46
Using a cognitive set to emotional facial expression as a model, induced synchronization/desynchronization of the cortical theta- and alpha-activities were studied in adult healthy people under conditions of increased load on the working memory (additional task of the verbal stimuli recognition). A correlation was found between behavioral (increase in the set rigidity) and electrophysiological (decrease of the induced theta-rhythm synchronization) data. A hypothesis is suggested that the earlier revealed increase in the tonic prestimulus theta-activity and suppression of the poststimulus phasic activation of the cortico-hippocampal system are one of the mechanisms of the decrease in plasticity of the cognitive function of the emotional facial expression recognition under conditions of the increased load on the working memory. Reciprocal relations between two functional systems of the brain activity integration (cortico-hippocampal and fronto-thalamic) in the process of recognition of emotional facial expression are discussed. 相似文献
5.
Coherence at the frequency of θ, α, and β 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 (reference)
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 θ-related functional coupling between medial areas of the frontal cortex and temporal cortical zones and by
a strengthening of local β-related functional connectivity in the fronto-central areas of the cortex. In children, no such
increase was found for θ rhythm; for β 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 α coherence in distant fronto-parietal links, predominantly
in the right hemisphere, while in children information retention was accompanied by the growth of θ 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
6.
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
7.
E. A. Kostandov 《Human physiology》2010,36(5):510-517
The hypotheses that the plasticity or flexibility of cognitive activity substantially depends on the ability to replace the
previous cognitive sets by new sets that are more appropriate to new conditions is substantiated. Working memory overload
results in a decrease in set-shifting and, as a consequence, increased erroneous stimuli recognition. The plasticity of set-shifting
is changed depending on the context of cognitive activity. On the basis of the data from the analysis of the coherence function
and induced synchronization/desynchronization responses of potentials in the θ (4–7 Hz) and low-frequency α (8–10 Hz) bands,
the roles of the tonic and phasic forms of activity of the cortico-hippocampal and fronto-thalamic functional systems of cerebral
integration in changes of plasticity of cognitive functions are discussed. 相似文献
8.
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
9.
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
10.
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
11.
The power spectra of cortical potentials of baseline activity during interstimulus intervals (4 s; Fourier transform in the
frequency band of 1–60 Hz) and short-term (0.8 s) induced responses to facial stimuli (wavelet transform in the 15–60 Hz band)
were assessed during the study of the visual cognitive set to facial expression. Significant differences between groups of
subjects with different set plasticities were observed only at the set-testing stage. Estimation of short-term (0.8 s) induced
responses of wavelet spectra in the group with the plastic set revealed an increase in the power (compared to the power of
background activity) of the γ2 band (41–60 Hz) in the temporal, central and occipital areas of the left hemisphere, whereas in the group with the rigid
set these power spectra decreased. At the same time, the power in the γ1 band (21–40 Hz) was significantly lower (at the same level with the rigid form), indicating the discrete nature and functional
selectivity in the γ frequency band. 相似文献
12.
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
13.
The dynamics of power of short-term (0.8 s) induced responses to facial stimuli (wavelet transform in the 15-60 Hz band) were assessed in the study of the visual cognitive set under conditions of different loads on working memory in two groups of subjects. Subjects of the first group had to react only to facial stimuli (n = 29), whereas the second group solved an additional task loading the working memory (they had to find a target stimulus in a matrix of letters, n = 35). We estimated wavelet spectra in the occipital, temporal, central and frontal areas of both hemispheres. In both groups of subjects with the plastic form of set, the power level in the gamma2 band (41-60 Hz) was significantly higher than in subject with the rigid form. In group A at the set-testing stage, the largest increase in the gamma2 band was related to the central areas of the left hemisphere. In more complex situation (group ), the increase in power in the gamma2 and gamma1 (21-40 Hz) bands was observed in the occipital and temporal areas of both hemispheres. At the same time, the EEG power of the central areas in these gamma bands was significantly lower. In the frontal areas there were no significant differences in the dynamics of power between the subjects of both groups. 相似文献
14.
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
15.
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
16.
Kostandov EA Kurova NS Cheremushkin EA Petrenko NE Ashkinazi ML Iakovenko IA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2008,58(2):163-171
The effect of increasing working memory load (by introduction of an additional cognitive task into the experimental context) on the recognition of emotional facial expression in a visual set paradigm was studied in healthy adult subjects. The link between plasticity of the cognitive set to emotional facial expression and the working memory was revealed. It was found that an increase in the working memory load was associated with a delay of set shifting in a modified situation. The set became more rigid which appeared as increasing number of trials with erroneous assessments of facial expression in the form of contrast or assimilative illusions. The significance of inner states and priming for the insight into psychophysiological mechanisms of erroneous assessments under conditions of the working memory loading is discussed in terms of the concept of the integration of bottom-up and top-down streams. 相似文献
17.
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
18.
Gender differences in electroencephalographic activity (EEG) changes during navigation task performance after training were
assessed in young adults. Female and male subjects were matched on initial navigation performance. EEG recordings were obtained
while subjects navigated in an immersive virtual environment without visual cues, before and after a navigational skills training
(9 sessions). In spite of task performance was similar in both groups, females showed higher theta band coherent activity
between frontal and parietal and frontal and central regions than males before training. Correlation in theta band between
fronto-central, fronto-parietal, and centro-parietal regions was enhanced in the left hemisphere for females but in the right
hemisphere for males after training. Females also demonstrated a decreased in correlation in theta band over the right hemisphere
between centro-parietal regions, whereas males demonstrated a similar effect over the left hemisphere. Navigation training
seems to promote fronto-central-parietal synchronization in both genders but in different hemisphere. These results are interpreted
as reflecting verbal-analytical working memory functions in females and global-spatial working memory mode in males. 相似文献
19.
The subjects were divided into two groups according to the α1 and α2 spectral powers in the occipital derivations of the EEG recorded in the initial state with their eyes closed. Group I included
subjects whose α1-rhythm spectral power (7–10 Hz) was more than 70% of the total α-rhythm band power. Group II included subjects whose α2-rhythm spectral power (10–13 Hz) was more than 70% of the total α-rhythm band power. It was established that, in the tasks
requiring prediction of the subsequent result (memorizing a certain sequence of signals and its subsequent reproduction on
the monitor screen), group I subjects differed from group II subjects in fewer sequence errors and a greater number of accurate
predictions. In group II subjects, a decrease in the ϑ-band spectral power in the EEG of the central and frontal cortical
areas was observed compared to the baseline. Therefore, the EEG ϑ-rhythm power at the memorizing stage was lower in them than
in group II subjects. The results suggest that the baseline characteristics of ϑ-activity can be regarded as prognostic criteria
of similar types of activity. 相似文献
20.
This study investigated the spatial, spectral, temporal and functional proprieties of functional brain connections involved in the concurrent execution of unrelated visual perception and working memory tasks. Electroencephalography data was analysed using a novel data-driven approach assessing source coherence at the whole-brain level. Three connections in the beta-band (18-24 Hz) and one in the gamma-band (30-40 Hz) were modulated by dual-task performance. Beta-coherence increased within two dorsofrontal-occipital connections in dual-task conditions compared to the single-task condition, with the highest coherence seen during low working memory load trials. In contrast, beta-coherence in a prefrontal-occipital functional connection and gamma-coherence in an inferior frontal-occipitoparietal connection was not affected by the addition of the second task and only showed elevated coherence under high working memory load. Analysis of coherence as a function of time suggested that the dorsofrontal-occipital beta-connections were relevant to working memory maintenance, while the prefrontal-occipital beta-connection and the inferior frontal-occipitoparietal gamma-connection were involved in top-down control of concurrent visual processing. The fact that increased coherence in the gamma-connection, from low to high working memory load, was negatively correlated with faster reaction time on the perception task supports this interpretation. Together, these results demonstrate that dual-task demands trigger non-linear changes in functional interactions between frontal-executive and occipitoparietal-perceptual cortices. 相似文献