Cílem této studie bylo představit české veřejnosti návrh clusteringu a switchingu v testu verbální fluence (VF), adaptovat vybrané klasifikace do českého prostředí a posoudit jejich relevanci. Článek se zabývá hodnocením uspořádání slov do celků (tzv. clusterů) a plynulosti přepínání mezi nimi (switching). Tento v zahraničí rozšířený přístup k analýze protokolů VF nebyl doposud v češtině systematizován. Čtenář je seznámen s teoretickým pozadím hodnocení clusterů a switchů ve fonologické verzi (PVF) i kategoriální verzi (SVF) a některými vybranými klasifikacemi – např. Troyer et al. (1997), Abwender et al. (2001), Libon et al. (2009) či Tallberg et al. (2011). Klasifikace Troyerové et al. (1997), která je celosvětově nejcitovanější, byla převzata a autoři článku se vyjádřili k jednotlivým pravidlům z pohledu českého jazyka i kulturního prostředí (Studie 1). Ve Studii 2 byly u deseti vybraných protokolů dvěma posuzovateli oskórovány fonematické clustery v PVF a sémantické clustery v SVF. Vypočtená shoda posuzovatelů ukázala v obou případech na dobrou až výbornou shodu. Jedná se o velmi slibný, nicméně stále teoretický koncept, jehož aplikace do praxe si žádá další zkoumání.

The main goal of this study was to introduce the evaluation procedure in Verbal fluency task – clustering and switching – to the Czech public, to adapt this procedure to the Czech language and to judge its relevance. The review focuses on the way of arranging the words into the clusters (so called clustering) and switching between them. This procedure is extended in foreign research but it has not yet been systematically adapted in the Czech context. In the article the theoretical background of clustering and switching in phonological verbal fluency (PVF) and also in semantic verbal fluency (SVF) is introduced and few classifications of clustering are described – e.g. Troyer et al. (1997), Abwender et al. (2001), Libon et al. (2009) and Tallberg et al. (2011). In Study 1, the most cited classification by Troyer et al. (1997) is adapted to the Czech language and the differences between the original version and Czech adaptation are discussed. In Study 2, ten protocols were rated by two raters and the inter-rater reliability was calculated. The value of Cohen,s kappa showed moderate to excellent agreement. This approach is very promising but it requires further research.

• MeSH
• fonetika MeSH
• lingvistika metody   MeSH
• neuropsychologické testy MeSH
• sémantika MeSH
• verbální chování klasifikace   MeSH
• Publikační typ
• práce podpořená grantem MeSH

Cognitive flexibility is a major requirement for successful goal-directed behavior and their neurobiological underpinnings are becoming better understood. However, the role of the norepinephrine system during task switching is largely enigmatic, despite neurobiological considerations make it likely that the norepinephrine system likely plays an important role. Theoretical considerations also suggest that the norepinephrine system mainly modulates task-switching processes when these rely upon working memory mechanisms. This topic was examined in the current system neurophysiological study integrating event-related potential (ERP) with pupil diameter data as a proximate the norepinephrine system activity. Combined with source localization methods, human brain structure, brain function, and phasic modulations by an important neurobiological system were integrated. The results show that cognitive-neurophysiological subprocesses during the actual switching processes, reflected by the N2 and P3 ERP components, are not modulated by the norepinephrine system. Rather, this system modulates preparatory processes in the fore period of stimuli signaling possible switches of response sets. The source localization results show that this is achieved by modulating neural processes in the temporo-parietal junction (BA40). Importantly, these phasic modulatory effects of the norepinephrine system were only evident when working memory processes had to be used to guide the selection of the appropriate responses for task switching.

• MeSH
• dospělí MeSH
• elektroencefalografie MeSH
• evokované potenciály fyziologie   MeSH
• kognice fyziologie   MeSH
• lidé MeSH
• mapování mozku * MeSH
• mladý dospělý MeSH
• noradrenalin fyziologie   MeSH
• paměť fyziologie   MeSH
• podněty MeSH
• pozornost fyziologie   MeSH
• pupila MeSH
• reakční čas fyziologie   MeSH
• temenní lalok fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Task switching processes reflect a faculty of cognitive flexibility. The underlying neural mechanisms and functional cortical networks have frequently been investigated using neurophysiological (EEG) or functional imaging methods. However, task switching processes are subject to strong intra-individual variability, especially when tested under varying levels of working memory demands. This intra-individual variability compromises the reliable estimation of neurophysiological processes and related functional neuroanatomical networks. In this study, we combine residue iteration decomposition (RIDE) of event-related potentials (ERPs) and source localization methods to circumvent this problem. Due to strong intra-individual variability, behavioral effects between memory-based and cue-based task switching were not reflected by classical ERPs, but were so after applying RIDE. Using RIDE, modulations paralleling the behavioral data were specifically reflected by processes related to the updating of internal representations for response selection (reflected by the C-cluster in the P3-component time range) rather than by stimulus and motor-related processes (reflected by the S-cluster and R-cluster). The C-cluster-processes were associated with activation differences in the inferior parietal cortex, including the temporo-parietal junction (TPJ, BA40) and likely reflect mechanisms related to the updating of internal representations and task sets for response selection. The results underline the necessity to use temporal decomposition methods to control the problem of intra-individual signal variability to decipher the neurophysiology and functional neuroanatomy of cognitive processes.

• MeSH
• dospělí MeSH
• elektroencefalografie metody   MeSH
• evokované potenciály MeSH
• individualita MeSH
• kognice fyziologie   MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mozková kůra fyziologie   MeSH
• nervové dráhy fyziologie   MeSH
• paměť fyziologie   MeSH
• počítačové zpracování obrazu MeSH
• počítačové zpracování signálu MeSH
• podněty * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The active place avoidance task is used in the research of spatial cognition. Rats are trained on a rotating arena to avoid an aversive stimulus delivered in a part of the room while being transported toward it by the arena rotation. The task tests the ability of rats to navigate with respect to distal cues in the room and to ignore confusing cues on the arena. The demand for cue segregation makes the task suitable for studying neural mechanisms responsible for cognitive coordination. An incidental observation made in our laboratory implied that overtrained rats may be able to solve the task without the room-bound cues. The aim of this study was to test this observation. The room-bound cues were hidden by switching off the lights. Rats trained only in darkness did not learn the task at all. Rats that were initially pre-trained in light performed considerably better. In a few exceptional dark sessions they even reached the level of performance observed in light. The rats needed the aversive stimuli to keep off the to-be-avoided sector. Without them, they continued their behavior, but with no spatial relationship to the to-be-avoided sector. We conclude that rats are able to solve the place avoidance task without the room-bound cues, but not as efficiently as in their presence.

• MeSH
• elektrický šok MeSH
• plnění a analýza úkolů MeSH
• podněty * MeSH
• potkani Long-Evans MeSH
• prostorové učení * MeSH
• psychologické testy MeSH
• tma MeSH
• učení vyhýbat se * MeSH
• zraková percepce MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Antagonistic activity of brain networks likely plays a fundamental role in how the brain optimizes its performance by efficient allocation of computational resources. A prominent example involves externally/internally oriented attention tasks, implicating two anticorrelated, intrinsic brain networks: the default mode network (DMN) and the dorsal attention network (DAN). To elucidate electrophysiological underpinnings and causal interplay during attention switching, we recorded intracranial EEG (iEEG) from 25 epilepsy patients with electrode contacts localized in the DMN and DAN. We show antagonistic network dynamics of activation-related changes in high-frequency (> 50 Hz) and low-frequency (< 30 Hz) power. The temporal profile of information flow between the networks estimated by functional connectivity suggests that the activated network inhibits the other one, gating its activity by increasing the amplitude of the low-frequency oscillations. Insights about inter-network communication may have profound implications for various brain disorders in which these dynamics are compromised.

• MeSH
• dospělí MeSH
• elektroencefalografie MeSH
• elektrofyziologické jevy MeSH
• epilepsie patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mozek * fyziologie   patofyziologie   MeSH
• nervová síť * fyziologie   MeSH
• pozornost * fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Úvod: Při přepínání pozornosti mezi dvěma úlohami, které obsahují stejný počet prvků jako úloha jediná, je pozorováno prodloužení času nazývané jako cena přepnutí „switch cost“. Cílem studie bylo zjistit vztah mezi rychlostí zpracování informací, pracovní pamětí a stářím při použití upravené verbální formy testu cesty. Verbální test cesty byl dále porovnáván s klasickým testem cesty. Metodika: U 137 zdravých dobrovolníků průměrného věku 45,5 ± 18,9 let (min. 20, max. 80 let) byl použit test cesty a verbální test přepínání mezi 1–4 kategoriemi. Byla měřena rychlost vyjmenování 12 slov v rámci jedné kategorie, 12 slov při střídání 2, 3 a 4 kategorií (měsíce, čísla, dny v týdnu, roční období). Výsledky: Při zachování stejného počtu slov rostl čas nutný k dokončení testu s přibývajícím počtem kategorií ANOVA (p < 0,001). Průměrný časový rozdíl mezi 1 a 2 kategoriemi byl 5 s. S každou další kategorií se cena přepnutí zvyšovala o cca 4 s. Byla zjištěna významná korelace mezi věkem a časem provedení testu cesty A i B (Pearsonovo r = 0,47 resp. R = 0,52) i střídáním 3 a 4 kategorií (r = 0,47 resp. r = 0,41). Nejvyšší korelace bylo dosaženo mezi verbálním testem střídání 4 kategorií a testem cesty B (r = 0,61, p < 0,001). Diskuze: Se zvyšováním nároků na pracovní paměť se výrazně prodlužuje doba k dokončení testu. S věkem dochází ke zpomalení psychického tempa, které může být na pozadí zhoršení pracovní paměti a dalších kognitivních funkcí.

Switching attention between two tasks takes longer than completing simple tasks that have the same number of particulars. This effect is called a switch cost. The aim of our study was to assess the relationships between psychomotor speed, working memory load, and age using an oral Trail Making Test (TMT). Then classical and oral version of TMT were compared. Methodology: 137 healthy volunteers were included with a mean age of 45.5 ± 18.9 years (min. 20, max. 80 years). We measured the time it took to recite 12 words from each category (months, numbers) and then the time it took to recite 12 switch words from 2, 3 and 4 routine sets (months, numbers, days of week, seasons). Results: The time taken to recite 12 words was significantly longer after adding each new category ANOVA (p<0.001). The difference in time between categories 1 and 2 was 5s. The switch cost increased by about 4s with every new category. A significant correlation was found between age, TMT parts A and B (Pearson’s r = 0.47 resp. r = 0.52), and 3-switch and 4-switch categories (r = 0.47 resp. r = 0.41). The highest correlation was found between TMT B and 4-switch categories (r = 0.61, p < 0.001). Discusion: We found association between working memory demand and the extension of time required to finish oral TMT. We also found that age correlated with mental speed, and therefore could form a base of impairment of working memory and other cognitive functions.

• Klíčová slova
• Disperdal r Consta TM,
• MeSH
• dospělí MeSH
• financování organizované MeSH
• interpretace statistických dat MeSH
• lidé MeSH
• neuropsychologie metody   statistika a číselné údaje   MeSH
• paměť fyziologie   MeSH
• pozornost fyziologie   MeSH
• psychologické testy statistika a číselné údaje   MeSH
• psychomotorický výkon fyziologie   MeSH
• stárnutí MeSH
• verbální chování fyziologie   MeSH
• verbální učení fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

Borrelia burgdorferi sensu lato (Spirochaetes) is a group of at least 12 closely related species, some of which are responsible for chronic zoonotic infection that may cause Lyme disease. The only experimentally confirmed vector transmitting Borrelia to mammals is the Ixodes ticks. Borrelia is a highly adapted pathogen that can survive in the host organism in spite of the intense immune responses. Some patients have chronic long-lasting complications despite antibiotic therapy, probably due to adverse effects of the immune responses. A preventive vaccine against this bacterium has not been available due to the relatively broad spectrum and antigenic variability of Borrelia-surface lipoproteins and the different epitope recognition by experimental animals and humans. Although a human vaccine was marketed in the USA, it has been already pulled off the market. In addition, this vaccine was effective only in the USA, where the only pathogenic species is B. burgdorferi sensu stricto. Recent data indicate that a broadly effective vaccine will to be composed of a mixture of several antigens or multiple epitopes.

• MeSH
• antigenní variace MeSH
• antigeny bakteriální imunologie   metabolismus   MeSH
• antigeny povrchové imunologie   MeSH
• autoimunitní nemoci etiologie   MeSH
• bakteriální proteiny imunologie   metabolismus   MeSH
• bakteriální vakcíny imunologie   MeSH
• Borrelia burgdorferi imunologie   metabolismus   MeSH
• klíště imunologie   metabolismus   mikrobiologie   MeSH
• lidé MeSH
• lipoproteiny imunologie   metabolismus   MeSH
• lymeská nemoc imunologie   mikrobiologie   patologie   prevence a kontrola   MeSH
• molekulární sekvence - údaje MeSH
• myši MeSH
• proteiny vnější bakteriální membrány imunologie   MeSH
• protilátky bakteriální imunologie   MeSH
• vakcinace škodlivé účinky   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Geografické názvy
• Spojené státy americké MeSH

The hippocampus (HPC) is essential for navigation and memory, tracking environmental continuity and change, including navigation relative to moving targets. CA1 ensembles expressing immediate-early gene (IEG) Arc and Homer1a RNA are contextually specific. While IEG expression correlates with HPC-dependent task demands, the effects of behavioral demands on IEG-expressing ensembles remain unclear. In three experiments, we investigated the effects of context switch, sustained presence, and task demands on dorso-proximal CA1 IEG+ ensembles in rats. Experiment 1 showed that the size of IEG+ (Arc, Homer1a RNA) ensembles dropped to baseline during uninterrupted 30-min exploration, reflecting familiarization, unless a context switch was present. Context-specificity of the ensembles depended on both environment identity and timing of the context switch. Experiment 2 found no effect of HPC-dependent mobile robot avoidance or HPC-independent avoidance of a stationary robot on IEG+ ensembles beyond mere exploration. Experiment 3 replicated these findings for c-Fos protein. The data suggest that IEG+ ensembles are driven by a context switch and shrink over time during sustained presence in the same environment. We found no evidence of task demands or their change affecting the size, stability over time, or task-specificity of IEG+ ensembles. These results shed light on the temporal dynamics of CA1 IEG+ ensembles, and their control by contextual and behavioral factors.

• MeSH
• chování zvířat fyziologie   MeSH
• cytoskeletální proteiny genetika   metabolismus   MeSH
• hipokampální oblast CA1 * metabolismus   fyziologie   MeSH
• Homer scaffold proteiny * metabolismus   genetika   MeSH
• krysa rodu rattus MeSH
• okamžité časné geny * fyziologie   MeSH
• potkani Long-Evans * MeSH
• proteiny nervové tkáně genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The effects of high-dose ethanol intoxication on cognitive flexibility processes are not well understood, and processes related to hangover after intoxication have remained even more elusive. Similarly, it is unknown in how far the complexity of cognitive flexibility processes is affected by intoxication and hangover effects. We performed a neurophysiological study applying high density electroencephalography (EEG) recording to analyze event-related potentials (ERPs) and perform source localization in a task switching paradigm which varied the complexity of task switching by means of memory demands. The results show that high-dose ethanol intoxication only affects task switching (i.e. cognitive flexibility processes) when memory processes are required to control task switching mechanisms, suggesting that even high doses of ethanol compromise cognitive processes when they are highly demanding. The EEG and source localization data show that these effects unfold by modulating response selection processes in the anterior cingulate cortex. Perceptual and attentional selection processes as well as working memory processes were only unspecifically modulated. In all subprocesses examined, there were no differences between the sober and hangover states, thus suggesting a fast recovery of cognitive flexibility after high-dose ethanol intoxication. We assume that the gamma-aminobutyric acid (GABAergic) system accounts for the observed effects, while they can hardly be explained by the dopaminergic system.

• MeSH
• cingulární gyrus fyziologie   patofyziologie   MeSH
• dechové testy MeSH
• dospělí MeSH
• elektroencefalografie MeSH
• evokované potenciály fyziologie   MeSH
• GABA MeSH
• kognice fyziologie   MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mozek fyziologie   patofyziologie   MeSH
• nervový přenos fyziologie   MeSH
• otrava alkoholem patofyziologie   psychologie   MeSH
• plnění a analýza úkolů MeSH
• pozornost MeSH
• reakční čas MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Executive functions, like the capacity to control and organize thoughts and behavior, develop from childhood to young adulthood. Although task switching and working memory processes are known to undergo strong developmental changes from childhood to adulthood, it is currently unknown how task switching processes are modulated between childhood and adulthood given that working memory processes are central to task switching. The aim of the current study is therefore to examine this question using a combined cue- and memory-based task switching paradigm in children (N = 25) and young adults (N = 25) in combination with neurophysiological (EEG) methods. We obtained an unexpected paradoxical effect suggesting that memory-based task switching is better in late childhood than in young adulthood. No group differences were observed in cue-based task switching. The neurophysiological data suggest that this effect is not due to altered attentional selection (P1, N1) or processes related to the updating, organization, and implementation of the new task-set (P3). Instead, alterations were found in the resolution of task-set conflict and the selection of an appropriate response (N2) when a task has to be switched. Our observation contrasts findings showing that cognitive control mechanisms reach their optimal functioning in early adulthood.

• MeSH
• exekutivní funkce * MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• neuropsychologické testy MeSH
• paměť MeSH
• pozornost MeSH
• vývoj člověka * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH