The study investigated whether specific changes in phase synchrony in the beta 2 frequency band of EEG (25-35 Hz) occurred during a recognition task. The level of synchrony was examined between one hundred and eighty loci in the frontal and temporal lobes of eight epileptic patients with intracerebral electrodes; the EEG records were obtained during a visual oddball task. In each pair of records, the correlation curves were created from the sequence of correlation coefficients calculated. These curves consisted of irregular oscillations between the maximal and minimal r-values. Transient highly synchronized activity was observed during the whole time course of the experiment in all record pairs investigated and a significant relationship was found between the number of such episodes and the mean correlation coefficient (Spearman R 0.84; N 3240; p<0.001). On averaged curves, which were calculated using stimulus onsets as the trigger of averaging, a significant increase of the mean correlation coefficient in the post-stimulus epoch was found (p<0.01 after both target and non-target stimuli; t-test for dependent samples). As the cognitive demand significantly increases after stimulus presentation, the results are considered to be the first evidence from intracranial recording of increased synchronization in the beta 2 frequency band related to the cognitive activity., M. Kukleta ... [et al.]., and Obsahuje seznam literatury
Spatiotemporal dynamics of event-related potentials (ERP) evoked by non-target stimuli in a visual oddball experiment and the presence of coherent oscillations in beta 2 frequency band of decomposed EEG records from peristimulus period were investigated by means of intracranial electrodes in humans. Twenty-one patients with medically intractable epilepsy participated in the study. The EEG signal was recorded using platinum electrodes implanted in several cortical and subcortical sites. Averaged 2 s EEG records were analyzed. Task-specific EEG changes were found in each patient, ERPs were derived from 92 electrodes used (96 % of possible cases). In the majority of analysed cases, ERPs were composed of several distinct components, and their duration was mostly longer than 1 s. The mean onset of the first ERP component was 158±132 ms after the stimulus (median 112 ms, minimum value 42 ms, maximum value 755 ms), and large variability of these onset times was found in all the investigated structures. Possible coherence between neural activities of remote brain sites was investigated by calculating running correlations between pairs of decomposed EEG records (alpha, beta 1, beta 2 frequency bands were used, total number of correlated pairs was 662 in each frequency band). The record pairs exhibiting highly correlated time segments represented 23 % of all the investigated pairs in alpha band, 7 % in beta 1 band, and 59 % in beta 2 band. In investigated 2 s record windows, such segments were distributed evenly, i.e. they were also found before the stimulus onset. In conclusion, the results have implicated the idea that a lot of recorded ERPs was more or less by-products of chance in spreading a signal within the neuronal network, and that their functional relevance was somewhat linked with the phenomenon of activity synchronization., M. Kukleta ... [et al.]., and Obsahuje seznam literatury
Desenzitizace a zpracování pomocí očních pohybů (EMDR) představuje terapeutickou metodu pro léčbu posttraumatické stresové poruchy s empiricky ověřovanou účinností. Výzkumy ukázaly, že EMDR snižuje živost a emocionalitu autobiografických vzpomínek a redukuje psychofyziologické nabuzení vlivem na autonomní nervový systém. Hypotézy o mechanismu účinku EMDR předpokládají aktivaci orientační reakce, procesů duální pozornosti a procesy analogické REM fázi spánku. Předpokládá se, že EMDR vyvolává funkční neurobiologické změny, které zefektivňují zpracování informací v centrální nervové soustavě, především u jedinců s posttraumatickou stresovou poruchou., Eye Movement Desensitization and Reprocessing (EMDR) represents a promising approach to treatment of posttraumatic stress disorder. The empirical findings provide evidence for the effect of EMDR on decreasing of subjectively perceived vividness and emotional burden of autobiographic memories and on reducing arousal of the autonomic nervous system by shifting the balance towards parasympathetic activation. Recent hypotheses suggest that the effects of EMDR rely on neurobiological mechanisms employed in dual focus attention, orienting reflex and REM sleep. This reprocessing seems to provoke a specific neurobiological response that makes the information processing in central nervous system more efficient, particularly in individuals with PTSD., Hana Vojtová, Petr Bob, Radek Ptáček., and Obsahuje seznam literatury
Narcismus je forma nezdravé sebelásky, často se spojuje s nedostatkem empatie k druhým, s arogancí, s přehnaným sebevědomím, nebo naopak velmi nízkým sebevědomím. První koncept narcismu představil v roce 1914 Sigmund Freud, který předpokládal, že všichni se rodíme do stavu tzv. primárního narcismu. Freud považoval narcismus za patologický až v dospělosti - takzvaný sekundární narcismus. Podle současných poznatků, doložených především Kernbergem a několika dalšími autory, je přiměřená míra narcismu vlastní každému jedinci, a náleží k ní i určitá adaptabilita, která napomáhá seberealizaci a uskutečňování životních cílů. V tomto kontextu autoři rozlišují normální osobnost, osobnost s narcistickými rysy a narcistickou poruchu osobnosti jako psychiatrickou diagnózu. Rozložení narcistických rysů v populaci se zkoumalo v mnohých studiích, které často poukazují na vztah narcismu a rizikového chování. Další studie poukazují také na možný vznik narcistické poruchy osobnosti, nebo narcistických rysů jako následek nepřiměřené rodičovské výchovy nebo traumatického stresu. Článek předkládá systematický pohled na vývoj konceptu narcismu, především v kontextu psychodynamické teorie., Narcissism is a form of unhealthy self-love, often associated with lack of empathy for others, the arrogance or very low self-esteem. The concept of narcissism was first introduced in 1914 by Sigmund Freud, who assumed that everyone is born into a condition called primary narcissism. Freud regarded narcissism as pathological lately in adulthood - the so-called secondary narcissism. According to the current knowledge, supported mainly by Kernberg and several other authors, an adequate level of narcissism is inherent in every individual, and it is connected to some degree of adaptability, which facilitates self-actualization and realization of life goals. In this context we distinguish normal personality, personality with narcissistic traits and narcissistic personality disorder as a psychiatric diagnosis. Distribution of narcissistic personality traits in the population was examined in many studies. They showed especially the relationship of narcissism and risk behavior. Other studies pointed to the possible development of narcissistic personality disorder, or narcissistic features as a result of inadequate parenting education or traumatic stress. The paper presents a systematic overview of the evolution of the concept of narcissism, especially in the context of psychodynamic theory., Petra Sélešová [et al.]., and Obsahuje seznam literatury
In this study, we tested the hypothesis that experimental stress induces a specific change of left-right electrodermal activity (EDA) coupling pattern, as indexed by pointwise transinformation (PTI). Further, we hypothesized that this change is associated with scores on psychometric measures of the chronic stress-related psychopathology. Ninety-nine university students underwent bilateral measurement of EDA during rest and stress-inducing Stroop test and completed a battery of self-report measures of chronic stress-related psychopathology. A significant decrease in the mean PTI value was the prevalent response to the stress conditions. No association between chronic stress and PTI was found. Raw scores of psychometric measures of stress-related psychopathology had no effect on either the resting levels of PTI or the amount of stress-induced PTI change. In summary, acute stress alters the level of coupling pattern of cortico-autonomic influences on the left and right sympathetic pathways to the palmar sweat glands. Different results obtained using the PTI, EDA laterality coefficient, and skin conductance level also show that the PTI algorithm represents a ne w analytical approach to EDA asymmetry description., M. Světlák ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy