69 resultados para non-conscious cognitive processing (NCCP) time.


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Background Non-AIDS defining cancers (NADC) are an important cause of morbidity and mortality in HIV-positive individuals. Using data from a large international cohort of HIV-positive individuals, we described the incidence of NADC from 2004–2010, and described subsequent mortality and predictors of these. Methods Individuals were followed from 1st January 2004/enrolment in study, until the earliest of a new NADC, 1st February 2010, death or six months after the patient’s last visit. Incidence rates were estimated for each year of follow-up, overall and stratified by gender, age and mode of HIV acquisition. Cumulative risk of mortality following NADC diagnosis was summarised using Kaplan-Meier methods, with follow-up for these analyses from the date of NADC diagnosis until the patient’s death, 1st February 2010 or 6 months after the patient’s last visit. Factors associated with mortality following NADC diagnosis were identified using multivariable Cox proportional hazards regression. Results Over 176,775 person-years (PY), 880 (2.1%) patients developed a new NADC (incidence: 4.98/1000PY [95% confidence interval 4.65, 5.31]). Over a third of these patients (327, 37.2%) had died by 1st February 2010. Time trends for lung cancer, anal cancer and Hodgkin’s lymphoma were broadly consistent. Kaplan-Meier cumulative mortality estimates at 1, 3 and 5 years after NADC diagnosis were 28.2% [95% CI 25.1-31.2], 42.0% [38.2-45.8] and 47.3% [42.4-52.2], respectively. Significant predictors of poorer survival after diagnosis of NADC were lung cancer (compared to other cancer types), male gender, non-white ethnicity, and smoking status. Later year of diagnosis and higher CD4 count at NADC diagnosis were associated with improved survival. The incidence of NADC remained stable over the period 2004–2010 in this large observational cohort. Conclusions The prognosis after diagnosis of NADC, in particular lung cancer and disseminated cancer, is poor but has improved somewhat over time. Modifiable risk factors, such as smoking and low CD4 counts, were associated with mortality following a diagnosis of NADC.

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BACKGROUND: We investigated the psychometric properties of a short questionnaire for combined assessment of different perceived stress management skills in the general population and tested whether scores relate to physiological stress reactivity. METHODS: For psychometric evaluation, we determined the factor structure of the questionnaire and investigated its measurement invariance in the participant groups and over time in three different independent samples representing the general population (total N=332). Reliability was tested by estimating test-retest reliability, internal consistency, and item reliabilities. We examined convergent and criterion validity using selected criterion variables. For endocrine validation, 35 healthy non-smoking and medication-free men in a laboratory study and 35 male and female employees in a workplace study underwent an acute standardized psychosocial stress task. We assessed stress management skills and measured salivary cortisol before and several times up to 60 min (workplace study) and 120 min (laboratory study) after stress. Potential confounders were controlled. RESULTS: The factor structure of the questionnaire consists of five scales reflecting acceptably distinct stress management skills such as cognitive strategies, use of social support, relaxation strategies, anger regulation, and perception of bodily tension. This factor structure was stable across participant groups and over time. Internal consistencies, item reliabilities, and test-retest reliabilities met established statistical requirements. Convergent and criterion validity were also established. In both endocrine validation studies, higher stress management skills were independently associated with lower cortisol stress reactivity (p's<.029). CONCLUSIONS: Our findings suggest that the questionnaire has good psychometric properties and that it relates to subjective psychological and objective physiological stress indicators. Therefore, the instrument seems a suitable measure for differential assessment of stress management skills in the general population.

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In this study we investigated whether synaesthesia is associated with a particular cognitive style. Cognitive style refers to preferred modes of information processing, such as a verbal style or a visual style. We reasoned that related to the enriched world of experiences created by synaesthesia, its association with enhanced verbal and visual memory, higher imagery and creativity, synaesthetes might show enhanced preference for a verbal as well as for a visual cognitive style compared to non-synaesthetes. In Study 1 we tested a large convenience sample of 1046 participants, who classified themselves as grapheme-color, sound-color, lexical-gustatory, sequence-space, or as non-synaesthetes. To assess cognitive style, we used the revised verbalizer-visualizer questionnaire (VVQ), which involves three independent cognitive style dimensions (verbal style, visual-spatial style, and vivid imagery style). The most important result was that those who reported grapheme-color synaesthesia showed higher ratings on the verbal and vivid imagery style dimensions, but not on the visual-spatial style dimension. In Study 2 we replicated this finding in a laboratory study involving 24 grapheme-color synaesthetes with objectively confirmed synaesthesia and a closely matched control group. Our results indicate that grapheme-color synaesthetes prefer both a verbal and a specific visual cognitive style. We suggest that this enhanced preference, probably together with the greater ease to switch between a verbal and a vivid visual imagery style, may be related to cognitive advantages associated with grapheme color synaesthesia such as enhanced memory performance and creativity.

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Serial correlation of extreme midlatitude cyclones observed at the storm track exits is explained by deviations from a Poisson process. To model these deviations, we apply fractional Poisson processes (FPPs) to extreme midlatitude cyclones, which are defined by the 850 hPa relative vorticity of the ERA interim reanalysis during boreal winter (DJF) and summer (JJA) seasons. Extremes are defined by a 99% quantile threshold in the grid-point time series. In general, FPPs are based on long-term memory and lead to non-exponential return time distributions. The return times are described by a Weibull distribution to approximate the Mittag–Leffler function in the FPPs. The Weibull shape parameter yields a dispersion parameter that agrees with results found for midlatitude cyclones. The memory of the FPP, which is determined by detrended fluctuation analysis, provides an independent estimate for the shape parameter. Thus, the analysis exhibits a concise framework of the deviation from Poisson statistics (by a dispersion parameter), non-exponential return times and memory (correlation) on the basis of a single parameter. The results have potential implications for the predictability of extreme cyclones.

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Objectives- We investigated whether apoE genotypes correlate with cognitive functions in clinically healthy persons. Methods - In 1993 and 1995, we measured information processing speed, delayed free recall and semantic aspects of long-term memory in 227 men and 105 women aged 65 and over, a randomly selected subsample of the prospective Basel Study. Cardiovascular risk factors and education were assessed. Results -E2 were more prevalent in old-old (>75 years, 23.5% vs 15%) compared to E4 than in young-old (<75 years, 19.3% vs 23.5%). Taking into account age and education, subjects with ɛ3/ɛ4 or ɛ4/ɛ4 alleles (E4) performed lowest in all 3 tests compared to those homozygous for ɛ3 (E3) or carriers of one or two ɛ2 alleles (E2) (reaction time P=0.009, free recall P=0.05, WAIS-R vocabulary P<0.05). In old-old there was a significant difference between E2 and E4 for reaction time (P=0.02) and free recall (P<0.02) but not for vocabulary (P=0.086). In all 3 groups there were no significant changes after 2 years. The subgroup with the genotype ɛ2/ɛ4 performed consistently best in the cognitive tests. Cholesterol was significantly increased in the E4 and E3 group compared to the E2 group. Conclusion - ApoE genotype correlates with cognitive performance. The increased prevalence of E2 in the old-old and the significantly lower plasma cholesterol levels suggest differential morbidity and mortality as important factors influencing the prevalence of cognitive disorders in late life.

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Systematic differences in circadian rhythmicity are thought to be a substantial factor determining inter-individual differences in fatigue and cognitive performance. The synchronicity effect (when time of testing coincides with the respective circadian peak period) seems to play an important role. Eye movements have been shown to be a reliable indicator of fatigue due to sleep deprivation or time spent on cognitive tasks. However, eye movements have not been used so far to investigate the circadian synchronicity effect and the resulting differences in fatigue. The aim of the present study was to assess how different oculomotor parameters in a free visual exploration task are influenced by: a) fatigue due to chronotypical factors (being a 'morning type' or an 'evening type'); b) fatigue due to the time spent on task. Eighteen healthy participants performed a free visual exploration task of naturalistic pictures while their eye movements were recorded. The task was performed twice, once at their optimal and once at their non-optimal time of the day. Moreover, participants rated their subjective fatigue. The non-optimal time of the day triggered a significant and stable increase in the mean visual fixation duration during the free visual exploration task for both chronotypes. The increase in the mean visual fixation duration correlated with the difference in subjectively perceived fatigue at optimal and non-optimal times of the day. Conversely, the mean saccadic speed significantly and progressively decreased throughout the duration of the task, but was not influenced by the optimal or non-optimal time of the day for both chronotypes. The results suggest that different oculomotor parameters are discriminative for fatigue due to different sources. A decrease in saccadic speed seems to reflect fatigue due to time spent on task, whereas an increase in mean fixation duration a lack of synchronicity between chronotype and time of the day.

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BACKGROUND Vitamin D deficiency is prevalent in HIV-infected individuals and vitamin D supplementation is proposed according to standard care. This study aimed at characterizing the kinetics of 25(OH)D in a cohort of HIV-infected individuals of European ancestry to better define the influence of genetic and non-genetic factors on 25(OH)D levels. These data were used for the optimization of vitamin D supplementation in order to reach therapeutic targets. METHODS 1,397 25(OH)D plasma levels and relevant clinical information were collected in 664 participants during medical routine follow up visits. They were genotyped for 7 SNPs in 4 genes known to be associated with 25(OH)D levels. 25(OH)D concentrations were analyzed using a population pharmacokinetic approach. The percentage of individuals with 25(OH)D concentrations within the recommended range of 20-40ng/ml during 12 months of follow up and several dosage regimens were evaluated by simulation. RESULTS A one-compartment model with linear absorption and elimination was used to describe 25(OH)D pharmacokinetics, while integrating endogenous baseline plasma concentrations. Covariate analyses confirmed the effect of seasonality, body mass index, smoking habits, the analytical method, darunavir/r and the genetic variant in GC (rs2282679) on 25(OH)D concentrations. 11% of the interindividual variability in 25(OH)D levels was explained by seasonality and other non-genetic covariates and 1% by genetics. The optimal supplementation for severe vitamin D deficient patients was 300000 IU two times per year. CONCLUSIONS This analysis allowed identifying factors associated with 25(OH)D plasma levels in HIV-infected individuals. Improvement of dosage regimen and timing of vitamin D supplementation is proposed based on those results.

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The relationship between time in dreams and real time has intrigued scientists for centuries. The question if actions in dreams take the same time as in wakefulness can be tested by using lucid dreams where the dreamer is able to mark time intervals with prearranged eye movements that can be objectively identified in EOG recordings. Previous research showed an equivalence of time for counting in lucid dreams and in wakefulness (LaBerge, 1985; Erlacher and Schredl, 2004), but Erlacher and Schredl (2004) found that performing squats required about 40% more time in lucid dreams than in the waking state. To find out if the task modality, the task length, or the task complexity results in prolonged times in lucid dreams, an experiment with three different conditions was conducted. In the first condition, five proficient lucid dreamers spent one to three non-consecutive nights in the sleep laboratory. Participants counted to 10, 20, and 30 in wakefulness and in their lucid dreams. Lucidity and task intervals were time stamped with left-right-left-right eye movements. The same procedure was used for these condition where eight lucid dreamers had to walk 10, 20, or 30 steps. In the third condition, eight lucid dreamers performed a gymnastics routine, which in the waking state lasted the same time as walking 10 steps. Again, we found that performing a motor task in a lucid dream requires more time than in wakefulness. Longer durations in the dream state were present for all three tasks, but significant differences were found only for the tasks with motor activity (walking and gymnastics). However, no difference was found for relative times (no disproportional time effects) and a more complex motor task did not result in more prolonged times. Longer durations in lucid dreams might be related to the lack of muscular feedback or slower neural processing during REM sleep. Future studies should explore factors that might be associated with prolonged durations.

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Einleitung Aktuelle empirische Befunde deuten darauf hin, dass Sportler/innen durch Stress und erhöhte Angst eine reduzierte Effizienz bei der Entscheidungsfindung aufweisen (Wilson, 2008). Erklärt werden kann dieser Befund durch die Attentional-Control-Theory (ACT, Eysenck et al., 2007), die postuliert, dass aufmerksamkeitslenkende Prozesse unter Angst gestört werden. Um diese Annahme für komplexe Situationen im Sport zu prüfen, wurden Fußballspieler unter erhöhten und regulären Druckbedingungen verglichen. Methode Je 11 Experten und Nicht-Experten hatten aus der Perspektive des Abwehrspielers die Aufgabe, in zwei mal 24 Spielsituationen so schnell und korrekt wie möglich verbal anzugeben, welche Aktion der ballführende Spieler (in naher vs. ferner Spielsituation) nach Ausblendung der Szene ausführen wird. Während im ersten Block der Druck nicht erhöht wurde, wurden Druckbedingungen im zweiten Block u.a. durch eine Wettkampfsituation und „falscher“ Ergebnisrückmeldung gesteigert. Entscheidungs- und Blickverhalten (u.a. Anzahl Fixationen), Pupillengröße, Zustandsangst und „Mental Effort“ (Wilson, 2008) wurden erfasst. Neben Expertiseunterschieden wurde erwartet, dass erhöhte Angst die Entscheidungseffizienz sowie das Blickverhalten stört (ACT-Annahme), was mit 2 (Experten/Nicht-Experten) x 2 (nahe/ferne Spielsituation) x 2 (hohe/reguläre Druckbedingung) ANOVAs (? = .05) mit Messwiederholungen auf den letzten beiden Faktoren geprüft wurde. Ergebnisse Druckmanipulationen führten zu höherer Zustandsangst und größeren Pupillendurchmessern. Neben Expertiseunterschieden – Experten antworteten schneller, korrekter und zeigten ein situationsangepasstes visuelles Suchverhalten – wiesen beide Gruppen in Drucksituationen längere Antwortzeiten und höheren Mental Effort auf. Erhöhter Druck führte bei Experten zur Reduktion der Fixationsortwechsel für ferne Spielsituationen. Nicht-Experten differenzierten ihr Suchverhalten weder zwischen Bedingungen noch für Spielsituationen. Diskussion Die Resultate bestätigen die ACT-Annahme, dass Angst und Stress die sportliche Leistung durch längere Reaktionszeiten, höhere kognitive Anstrengung und ein teilweise ineffizientes visuelles Suchverhalten negativ beeinflusst. Eine gestörte Balance zwischen Top-Down und Bottom-Up-Prozessen könnte die Ursache sein (Eysenck et al., 2007). Literatur Eysenck, M. W., Derakshan, N., Santos, R., & Calvo, M. G. (2007). Anxiety and cognitive performance: Attentional control theory. Emotion, 7, 336–353. Wilson, M. (2008). From processing efficiency to attentional control: A mechanistic account of the anxiety-performance relationship. International Review of Sport and Exercise Psychology, 1, 184– 201. 2 Vorträge und Poster

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Strategies of cognitive control are helpful in reducing anxiety experienced during anticipation of unpleasant or potentially unpleasant events. We investigated the associated cerebral information processing underlying the use of a specific cognitive control strategy during the anticipation of affect-laden events. Using functional magnetic resonance imaging, we examined differential brain activity during anticipation of events of unknown and negative emotional valence in a group of eighteen healthy subjects that used a cognitive control strategy, similar to "reality checking" as used in psychotherapy, compared with a group of sixteen subjects that did not exert cognitive control. While expecting unpleasant stimuli, the "cognitive control" group showed higher activity in left medial and dorsolateral prefrontal cortex areas but reduced activity in the left extended amygdala, pulvinar/lateral geniculate nucleus and fusiform gyrus. Cognitive control during the "unknown" expectation was associated with reduced amygdalar activity as well and further with reduced insular and thalamic activity. The amygdala activations associated with cognitive control correlated negatively with the reappraisal scores of an emotion regulation questionnaire. The results indicate that cognitive control of particularly unpleasant emotions is associated with elevated prefrontal cortex activity that may serve to attenuate emotion processing in for instance amygdala, and, notably, in perception related brain areas.

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BACKGROUND The number of older adults in the global population is increasing. This demographic shift leads to an increasing prevalence of age-associated disorders, such as Alzheimer's disease and other types of dementia. With the progression of the disease, the risk for institutional care increases, which contrasts with the desire of most patients to stay in their home environment. Despite doctors' and caregivers' awareness of the patient's cognitive status, they are often uncertain about its consequences on activities of daily living (ADL). To provide effective care, they need to know how patients cope with ADL, in particular, the estimation of risks associated with the cognitive decline. The occurrence, performance, and duration of different ADL are important indicators of functional ability. The patient's ability to cope with these activities is traditionally assessed with questionnaires, which has disadvantages (eg, lack of reliability and sensitivity). Several groups have proposed sensor-based systems to recognize and quantify these activities in the patient's home. Combined with Web technology, these systems can inform caregivers about their patients in real-time (e.g., via smartphone). OBJECTIVE We hypothesize that a non-intrusive system, which does not use body-mounted sensors, video-based imaging, and microphone recordings would be better suited for use in dementia patients. Since it does not require patient's attention and compliance, such a system might be well accepted by patients. We present a passive, Web-based, non-intrusive, assistive technology system that recognizes and classifies ADL. METHODS The components of this novel assistive technology system were wireless sensors distributed in every room of the participant's home and a central computer unit (CCU). The environmental data were acquired for 20 days (per participant) and then stored and processed on the CCU. In consultation with medical experts, eight ADL were classified. RESULTS In this study, 10 healthy participants (6 women, 4 men; mean age 48.8 years; SD 20.0 years; age range 28-79 years) were included. For explorative purposes, one female Alzheimer patient (Montreal Cognitive Assessment score=23, Timed Up and Go=19.8 seconds, Trail Making Test A=84.3 seconds, Trail Making Test B=146 seconds) was measured in parallel with the healthy subjects. In total, 1317 ADL were performed by the participants, 1211 ADL were classified correctly, and 106 ADL were missed. This led to an overall sensitivity of 91.27% and a specificity of 92.52%. Each subject performed an average of 134.8 ADL (SD 75). CONCLUSIONS The non-intrusive wireless sensor system can acquire environmental data essential for the classification of activities of daily living. By analyzing retrieved data, it is possible to distinguish and assign data patterns to subjects' specific activities and to identify eight different activities in daily living. The Web-based technology allows the system to improve care and provides valuable information about the patient in real-time.

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Motor-performance-enhancing effects of long final fixations before movement initiation – a phenomenon called Quiet Eye (QE) – have repeatedly been demonstrated. Drawing on the information-processing framework, it is assumed that the QE supports information processing revealed by the close link between QE duration and task demands concerning, in particular, response selection and movement parameterisation. However, the question remains whether the suggested mechanism also holds for processes referring to stimulus identification. Thus, in a series of two experiments, performance in a targeting task was tested as a function of experimentally manipulated visual processing demands as well as experimentally manipulated QE durations. The results support the suggested link because a performance-enhancing QE effect was found under increased visual processing demands only: Whereas QE duration did not affect performance as long as positional information was preserved (Experiment 1), in the full vs. no target visibility comparison, QE efficiency turned out to depend on information processing time as soon as the interval falls below a certain threshold (Experiment 2). Thus, the results rather contradict alternative, e.g., posture-based explanations of QE effects and support the assumption that the crucial mechanism behind the QE phenomenon is rooted in the cognitive domain.

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Background Nowadays there is extensive evidence available showing the efficacy of cognitive remediation therapies. Integrative approaches seem superior regarding the maintenance of proximal outcome at follow-up as well as generalization to other areas of functioning. To date, only limited evidence about the efficacy of CRT is available concerning elder schizophrenia patients. The Integrated Neurocognitive Therapy (INT) represents a new developed cognitive remediation approach. It is a manualized group therapy approach targeting all 11 NIMH-MATRICS dimensions within one therapy concept. In this study we compared the effects of INT on an early course group (duration of disease<5 years) to a long-term group of schizophrenia outpatients (duration of disease>15 years). Methods An international multicenter study carried out in Germany, Switzerland and Austria with a total of 90 outpatients diagnosed with Schizophrenia (DSM-IV-TR) were randomly assigned either to an INT-Therapy or to Treatment-As-Usual (TAU). 50 of the 90 Patients were an Early-Course (EC) group, suffering from schizophrenia for less than 5 years (Mean age=29 years, Mean duration of illness=3.3 years). The other 40 were a Long-term Course (LC) group, suffering from schizophrenia longer than 15 years (Mean age= 45 years, Mean duration of illness=22 years). Treatment comprised of 15 biweekly sessions. An extensive assessment battery was conducted before and after treatment and at follow up (1 year). Multivariate General Linear Models (GLM) (duration of illness x treatment x time) examined our hypothesis, if an EC group of schizophrenia outpatients differ in proximal and distal outcome from a LC group. Results Irrespective of the duration of illness, both groups (EC & LC) were able to benefit from the INT. INT was superior compared to TAU in most of the assessed domains. Dropout rate of EC group was much higher (21.4%) than LC group (8%) during therapy phase. However, interaction effects show that the LC group revealed significantly higher effects in the neurocognitive domains of speed of processing (F>3.6) and vigilance (F>2.4). In social cognition the EC group showed significantly higher effects in social schema (F>2.5) and social attribution (blame; F>6.0) compared to the LC group. Regarding more distal outcome, patients treated with INT obtained reduced general symptoms unaffected by the duration of illness during therapy phase and at follow-up (F>4.3). Discussion Results suggest that INT is a valid goal-oriented treatment to improve cognitive functions in schizophrenia outpatients. Irrespective of the duration of illness significant treatment, effects were evident. Against common expectations, long-term, more chronic patients showed higher effects in basal cognitive functions compared to younger patients and patients without any active therapy (TAU). Consequently, more integrated therapy offers are also recommended for long-term course schizophrenia patients.