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S V Pavlov

Publications and source records attributed to S V Pavlov.

17 recordsLinked to original sources
PubMed2004

Analysis of evoked EEG synchronization and desynchronization in conditions of emotional activation in humans: temporal and topographic characteristics.

Studies in 20 healthy right-handed subjects analyzed evoked EEG synchronization and desynchronization in the delta, theta1, theta2, alpha1, alpha2, beta1, beta2, beta3, and gamma ranges in response to sequential presentation of stimuli from the International Affective Picture System (IAPS) with low, medium, and high emotional activation impact. Each signal presentation was accompanied by subjective scaling of the extent of its emotional impact. EEG traces were recorded in 62 channels as signals were presented. These experiments showed that the degree of emotional impact of the signal was significantly associated with increases in evoked synchronization in the delta, theta1, theta2, beta1, beta3, and gamma ranges and with the effects of combined changes in evoked synchronization and desynchronization in the alpha2 frequency range. The interhemisphere distribution of evoked changes in power provided evidence that not only the posterior areas of the right hemisphere were involved in analyzing the emotional significance of images, as indicated by changes in evoked theta1 and theta2 synchronization and alpha2 desynchronization, but also the anterior areas of the left hemisphere, as indicated by changes in evoked theta2 synchronization. From the standpoint of affective chronometry, the earliest discrimination of the emotional content of stimuli, regardless of the sign of the emotion, occurred in the lower theta range and was seen at 0-600 msec after the start of stimulus presentation. This process was delayed 600-1000 msec in the theta2, alpha2, and gamma ranges.

Adolescent↗
PubMed2003

Disruption of early event-related theta synchronization of human EEG in alexithymics viewing affective pictures.

The 62-channel EEG was recorded while control non-alexithymic (n=21) and alexithymic (n=20) participants viewed sequentially presented neutral, pleasant and unpleasant pictures and subjectively rated them after each presentation. The event-related synchronization (ERS) to these stimuli was assessed in the theta-1 (4-6 Hz) and theta-2 (6-8 Hz) frequency bands. The obtained findings indicate that alexithymia influences perception of only emotional stimuli. Over anterior cortical regions alexithymia vs. control individuals in response to both pleasant and unpleasant stimuli manifested decreased left hemisphere ERS in the early test period of 0-200 ms along with enhanced ERS in response to negative vs. positive and neutral stimuli in the right hemisphere at 200-600 ms after stimulus onset. The findings provide the first EEG evidence that alexithymia construct, associated with a cognitive deficit in initial evaluation of emotion, is indexed by disrupted early frontal synchronization in the upper theta band that can be best interpreted to reflect disregulation during appraisal of emotional stimuli.

Affective Symptoms↗
PubMed2003

[Effect of alexithymia on the event-related theta-synchronization of human EEG during reception of emotional visual stimuli].

The 62-channel EEG was recorded while control non-alexithymic (n = 21) and alexithymic (n = 20) participants viewed sequentially presented neutral, pleasant and unpleasant pictures and subjectively rated them after each presentation. The event-related synchronization (ERS) to these stimuli was assessed in the theta-1 (4-6 Hr) and theta-2 (6-8 Hz) frequency bands. The obtained findings indicate that alexithymia influences perception of only emotional stimuli. In the upper theta over anterior cortical regions alexithymia vs control individuals in response to both pleasant and unpleasant stimuli manifested decreased left hemisphere ERS in the early test period of 0-200 ms along with enhanced ERS in response to negative vs positive and neutral stimuli in the right hemisphere at 200-600 ms after stimulus onset. The findings provide the first EEG evidence that alexithymia construct, associated with a cognitive deficit in initial evaluation of emotion, is indexed by disrupted early frontal synchronization in the upper theta band that can be best interpreted to reflect disregulation during appraisal of emotional stimuli.

Affective Symptoms↗
PubMed2002

[Reflection of the emotion manifestation in effects of evoked EEG synchronization and desynchronization].

Event-related desynchronization (ERD) and synchronization (ERS) in response to neutral, positive and negative emotional IAPS stimuli were measured in narrow theta, alpha-1, alpha-2 and alpha-3 frequency bands in 22 healthy Ss. A high resolution 62-channel EEG was recorded while subjects viewed a sequence of pictures. The effects of valence discrimination related to hemispheric asymmetries are associated with increased theta and alpha-3 synchronization. Theta ERS revealed a significant valence by hemisphere interaction for anterior temporal leads in the time window of 100-700 ms after stimulus onset indicating a relatively greater right hemisphere ERS for negative and a left hemisphere ERS for positive stimuli in comparison to neutral those. In the alpha-3 band, negative stimuli induced a left hemisphere ERS increase (F7 site) in the time window of 800-1200 ms not observed for neutral and positive stimuli. The results obtained along with the earlier observations on EEG correlates of affective processing challenge the notion that effective anterior hemispheric asymmetries are reflected mainly in the wide alpha frequency band.

Adolescent↗
PubMed2001

Affective picture processing: event-related synchronization within individually defined human theta band is modulated by valence dimension.

Event-related desynchronization (ERD) and synchronization (ERS) in the theta frequency band was measured while subjects viewed stimuli with differing emotional content (from the International Affective Picture System). A significant valence by hemisphere interaction emerged only in the anterior temporal regions, showing relatively greater right hemisphere ERS for negative and left hemisphere ERS for positive stimuli. In turn, in the posterior brain regions affectively valenced vs neutral stimuli prompted larger extent of ERS against the background of the overall right hemisphere dominance in theta synchronization. The findings document that valence discrimination is associated with the early (200-500 ms poststimulus) time-locked synchronized theta activity as well as hemispheric asymmetries in anterior-posterior direction.

Adolescent↗
PubMed2001

[Mental disorders in patients with benign prostatic hyperplasia].

310 patients with benign prostatic hyperplasia have been studied. Their mental state being analyzed by clinical and psychometric methods using Spilberger and Hamilton scales. Neurotic disorders have been reported in all the patients: 53.8% having neurasthenic syndrome, 30% anxiety- or astheno-subdepressive syndrome, 16.2% neurotic hypochondriac symptomatology. After treatment with minor neuroleptics, antidepressants and tranquilizers, patients' psychic state improved, even when the objective urologic data remained unchanged. Treatment of mental disorders makes it possible to prepare a patient for the operation and to improve quality of life of patients with benign prostatic hyperplasia before the operation.

Aged↗
PubMed1997

[An information support system for managing the environmental status in the Republic of Bashkortostan].

The main function of informational system supporting environmental control in Bashkortostan Republic is to prevent and liquidate accidents, to provide operative and complete information on current and future state of environment. Functioning of the system is supported by geological informational structure, ecologic databases, space information processor, broad system of mathematic models incorporated into local computer network.

Bashkiria↗
PubMed1997

[The biomonitoring subsystem of the Republic of Bashkortostan for assessing environmental quality].

General integrated system evaluates the state of soil, waters and atmosphere through natural biotest organisms and monitors anthropogenic changes in environment. The topics discussed are modern methods of soil, waters and atmosphere monitoring, main parameters for ecologic regulation of toxic chemicals, creation of biomonitoring subsystem in whole ecologic control. Efficiency of studies aimed at creation of biomonitoring subsystem depends on systematic investigations of anthropogenic influence on living creatures and on assessment of integral parameters describing biologic environment and characterizing jeopardy of various polluters.

Animals↗
PubMed1997

[Geographical informational technology as the basis for the informational integration for the large-scale evaluation of the environment].

Complex evaluation of environmental state requires processing of extensive information describing various components and objects of environment. Characteristic of this information is territory fix--each environmental object has definite geographic position and border. The authors discuss effects of up-to-date geographic information technologies on evaluation of environmental state in Bashkortostan Republic. Examples of analysis and simulation of possible changes in environmental state are given.

Bashkiria↗
PubMedDate not supplied

[Diagnostic scale of infravesical obstruction in patients d with benign prostatic hyperplasia].

A clinical diagnostic scale of infravesical obstruction (IVO) in patients with benign prostatic hyperplasia is proposed which provides the diagnosis of IVO in BPH patients with probability up to 89% basing only on clinical evidence obtained at a detailed urological examination (size of the gland, size and index of the prostatic transitional zone, residual urine, micturition urine, maximal micturition rate).

Humans↗
PubMedDate not supplied

[Transurethral rotoresection - a new method of benign prostatic hyperplasia treatment].

Karl Storz company (Germany) offers a novel endoscopic technology in the treatment of benign prostatic hyperplasia (BPH) i.e. rotoresection which combined mechanic and electrosurgical methods of removal of the hyperplastic tissue. The operation is performed with application of a special rotoresectoscope connected with a rotor electrode which, in its turn, is connected with mechanical rotor generator making it to rotate and with powerful electrogenerator (radiotome). The hyperplastic tissue is removed both mechanically (by high-frequency rotation of the rotor tip) and due to electrovaporization with simultaneous coagulation of the underlying tissue layers. Transurethral rotoresection was performed in 40 patients with BPH. Intraoperative and postoperative complications were not observed. Examination at discharge and 1 month after surgery showed a 4-fold decrease in the prostatic symptoms by IPSS scale, residual urine decreased 3-fold, maximal urine flow rate rose 2.5-fold. Transurethral rotoresection combines effective removal of BPH tissue with minimal intraoperative bleeding. It is a good alternative to conventional TUR. For more detailed evaluation further studied are needed.

Cystoscopes↗
PubMedDate not supplied

[Analysis of elicited EEG synchronization and desynchronization in emotional activation: temporal and topographic characteristics].

Event-related synchronization (ERS) and desynchronization (ERD) in delta, theta1, theta2, alpha1, alpha2, beta1, beta2, beta3, and gamma were measured in 20 healthy right-handed subjects in response to IAPS stimuli with low, moderate, and high arousal reactions. The 62-channel EEG was simultaneously recorded while subjects viewed sequentially presented pictures and subjectively rated them after each presentation. The results show that emotionally loaded stimuli induced higher ERS in the delta, theta1, theta2, beta1, beta3, and gamma bands along with combined ERD and ERS effects in alpha2 band. As to hemispheric asymmetries, the effects of emotional arousal were restricted not only to right parietal (theta1 and theta2 ERS, alpha2 ERD) but also to left frontal (theta2 ERS) regions. In terms of affective chronometry, lower theta was the first to catch the affective salience of incoming stimuli (time window 0-600 ms after the stimulus input). For theta2, alpha2, and gamma bands this process was delayed to 600-1000 ms.

Adolescent↗
PubMedDate not supplied

[Event-related synchronization and desynchronization of EEG during appraisal of threatening and pleasant visual stimuli in high anxious subjects].

The 62-channel EEG was recorded while low (LA, n = 18) and high (HA, n = 18) trait-anxious subjects viewed sequentially presented neutral, threatening and pleasant IAPS stimuli. Event-related desynchronization (ERD) and synchronization (ERS) were studied in the delta, theta1, theta2, alpha1, alpha2, beta1, beta2, beta3, and gamma frequency bands. Between-group differences, related to stimulus emotionality, were linked to theta1 and theta2 bands. In the low theta at prefrontal sites in the test period of 100-700 ms after stimulus onset HA exhibited relative predominance of the left hemisphere in response to both threatening and pleasant stimuli, whereas LA yielded larger right than left hemisphere activity in response to all the three stimulus categories. In the upper theta band between group differences were associated with posterior cortical regions and the test period of 0-1000 ms after stimulus onset: HA exhibited the largest ERS to threatening, whereas LA prompted the largest ERS to pleasant stimuli. Finally, according to the ERD data, in the alpha1 band HA participants in comparison with LA revealed enhanced left hemisphere activation in response to all the stimulus categories. It is suggested that as it is indexed by theta-ERS relative predominance of the left hemisphere at prefrontal sites along with the largest bilateral activity of posterior cortical regions (i.e., enhanced higher order visual processing) to threatening stimuli could form the basis for general bias towards threatening information in HA at the very early stages of emotional processing.

Adolescent↗
PubMedDate not supplied

[Extracorporeal shock-wave therapy in Peyronie's disease].

The aim of the study was to validate clinical methodology on application of shock-wave impact on plaques in Peyronie's disease (PD). We studied short- and long-term results of extracorporeal shock-wave therapy (ESWT) in 54 patients 3, 6 and 12 months after the exposure. We performed ESWT sessions on different lithotriptors using different mechanisms of shock wave mechanism (hydromechanical and piezoelectric). Choice of the ESWT technique was based on the thickness and density of the plaque. The proposed ESWT method provides an effective treatment of the disease basing on the initial angle of penis deformation in erection.

Adult↗
PubMedDate not supplied

[Characteristics of interhemispheric EEG band power distribution in high anxiety individuals under emotionally neutral and aversive arousal conditions].

The 62-channel EEG was recorded in control (CI, n = 21) and high anxiety (HA, n = 18) individuals under emotionally neutral (eyes closed, eyes open, and neutral videoclip) as well as under emotionally positive and aversive arousal conditions elicited by affective videoclips. In the present study the first three experimental conditions (eyes closed--eyes open--viewing emotionally neutral films) modeled increasing non-emotional arousal. Findings from this continuum show that in the HA individuals the lowest level of tonic arousal (eyes closed) was associated with stronger right-sided parietotemporal theta1 and beta1 activity. Group differences during cortical arousal increased by sensory stimulation (eyes open, neutral clips presentation) were marked only by persisting favored right hemisphere beta1 activity in high anxiety individuals. Under aversive arousal condition, attended by high intensity experience of emotions of anger, fear, disgust and anxiety, the HA subjects selectively desynchronized the right parietotemporal beta1 power which was initially higher in the control conditions. The obtained findings allow to suggest that peculiarities of right-sided parietotemporal EEG theta1 and beta1 activity in HA individuals under studied emotionally neutral and aversive arousal conditions point to overactivated withdrawal system in "checking" and "control" modes.

Anxiety↗