536 research outputs found

    Kognitive Testung in Laborstudien: Motivationsverlust oder Last Test Effect?

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    Fragestellung Wenn Probanden in Laborstudien längerer Dauer eine Vielzahl kognitiver Testbatterien wiederholt durchführen, wird häufig befürchtet, dass sich ein Motivationsverlust der Probanden einstellen könnte, die Tests mit immer gleichem Engagement durchzuführen. Zudem ist fraglich, ob die letzte Testung durch die Aussicht auf das bevorstehende Studienende beeinflusst und somit in ihrer Aussagekraft eingeschränkt wird. Diese beiden Themen wurden anhand einer Laborstudie untersucht. Methoden Die kognitive Leistung von 47 gesunden Probanden (mittleres Alter 27 ± 5 (SD) Jahre, 21 Frauen) wurde in 3-stündigen Intervallen während eines 12-tägigen Studienprotokolls getestet so dass insgesamt 65 Tests eines Psychomotorischen Vigilanztests (PVT) und eines Hand-Auge-Koordinationstests (UTT) absolviert wurden. Nach Basismessungen (8 Stunden Schlafzeit) wurden drei Schlafentzugsbedingungen in einem balancierten cross-over Design dargeboten. Nach jeder Intervention erholten sich die Probanden während zwei Nächten und Tagen. Am letzten Studientag wurden 24 Probanden im Vorhinein darüber informiert, dass es sich bei Test 65 um den letzten Test handelte, während 23 Probanden davon ausgingen, dass sich drei Stunden später noch ein weiterer Test anschließen würde. Ergebnisse Eine mixed ANOVA, die die kognitive Leistung am Basistag und am jeweils 2. Erholungstag berücksichtigte, ergab, dass sich die Geschwindigkeit (p=0,3475) und Lapses (p=0,2429) im PVT im Studienverlauf nicht veränderten. Der UTT (p=0,0211) verbesserte sich. Eine 2-way mixed ANOVA mit den Faktoren Gruppe (wissend/unwissend) und Test (Basis/Test 65) sowie deren Interaktion zeigte, dass im Vergleich zum Basistag die letzte Testleistung im PVT besser (Geschwindigkeit: p0,5). Schlussfolgerung Die Ergebnisse legen nahe, dass es möglich ist, die Motivation und das Engagement der Probanden für immer wiederkehrende kognitive Testverfahren über einen längeren Zeitraum aufrechtzuerhalten. Es ergaben sich keine Hinweise auf einen ‚Last Test Effect‘

    Impact Of Sleep Restriction And Recovery On Motivation During Repeated Cognitive Performance Testing

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    Introduction: Both motivation and sleep deprivation affect cognitive performance. Especially during long-lasting studies with repeated cognitive performance tasks there is concern that subjects will lose motivation over time. Results may be confounded due to changes in motivation. Methods: In an ongoing study, 29 healthy volunteers performed 55 cognitive performance tasks at three-hourly intervals in a 12-day inpatient study. After two baseline nights with 8 h time in bed (TIB) the intervention group (N=20; mean age 26 ± 4 years, 9 females) underwent chronic sleep restriction for 5 nights (5 h TIB) with a following recovery night of 8 h TIB. The control group (N=9; mean age 25 ± 5 years, 3 females) had the opportunity to sleep 8 hours every night. Participants completed the Karolinska Sleepiness Scale (KSS) and a questionnaire about their motivation (from 1=very little/not motivated to 5=very motivated) at 6 p.m. on all days. Results: Wilcoxon signed-rank tests showed a significant decrease in motivation (p=.0439) and a significant increase in subjective sleepiness (p=.0184) from baseline (motivation: 2.8 ± 0.6 (SD), sleepiness: 3.2 ± 1.2) to the last day of chronic sleep restriction (motivation: 2.2 ± 0.5, sleepiness: 5.1 ± 1.8) for the experimental group. Motivation remained low after recovery sleep (2.2 ± 0.8; p=.0198). Sleepiness and motivation scores showed a significant Spearman correlation (r=-0.43, p<0.001). Discussion: Chronic sleep restriction for five days leads to an increase in sleepiness and a decrease in motivation. One night of recovery is insufficient to reverse the motivation loss, contrasting with the beneficial effect on sleepiness. During chronic sleep restriction conditions subjective motivation seems to decrease as a function of subjective sleepiness

    Nocturnal air, road, and rail traffic noise and daytime cognitive performance and annoyance

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    Various studies indicate that at the same noise level and during the daytime, annoyance increases in the order of rail, road, and aircraft noise. The present study investigates if the same ranking can be found for annoyance to nocturnal exposure and next day cognitive performance. Annoyance ratings and performance change during combined noise exposure were also tested. In the laboratory 72 participants were exposed to air, road, or rail traffic noise and all combinations. The number of noise events and LAS,eq were kept constant. Each morning noise annoyance questionnaires and performance tasks were administered. Aircraft noise annoyance ranked first followed by railway and road noise. A possible explanation is the longer duration of aircraft noise events used in this study compared to road and railway noise events. In contrast to road and rail traffic, aircraft noise annoyance was higher after nights with combined exposure. Pooled noise exposure data showed small but significant impairments in reaction times (6 ms) compared to nights without noise. The noise sources did not have a differential impact on performance. Combined exposure to multiple traffic noise sources did not induce stronger impairments than a single noise source. This was reflected also in low workload ratings

    Interindividual variabilities in cognitive performance degradation after alcohol consuption and sleep loss are related

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    Introduction The sleep inducing effects of alcohol as well as the increase in sleep propensity and sleepiness after sleep loss have been linked to the adenosinergic system in the brain. While the performance impairing effects of ethanol have partly been related to the inhibitory effects of cerebral adenosine, sleep loss has been found to increase adenosine receptor density. The interindividual variability of cognitive performance impairments after alcohol intake as well as after sleep loss is extensive. Thus, we examined in humans whether performance degradations resulting from sleep loss and alcohol consumption are related. Methods Performance in a 10-min Psychomotor Vigilance Task (PVT) was tested in 47 healthy volunteers (mean age 27 ± 5 (SD) years, 21 females) at 6 pm 1) after an 8 hour control night, 2) after alcohol consumption (aiming at a blood alcohol concentration (BAC) of 0.08%), and 3) after 35 hours of total sleep deprivation. After alcohol intake, 35 of the participants reached a BAC of more than 0.06% prior to the performance testing (mean BAC 0.074%, SD 0.009%, min. 0.063%, max. 0.095%) and were included in the analyses. Two recovery nights were scheduled between conditions. Results Performance impairments due to acute alcohol intake and due to 35 hours of sustained wakefulness were calculated as differences from performance under control conditions. The degree in performance degradation correlated highly between both conditions (i.e. 10% slowest reaction times: Pearson’s r=0.73, p<0.0001; standard deviation of reaction times: r=0.75, p<0.0001; mean reaction time: r=0.59, p=0.0002). Conclusions Participants whose PVT performance proved to be vulnerable to the effects of alcohol consumption were also vulnerable to sleep loss, whereas individuals who were resilient against the effects of alcohol were also less susceptible to the impact of sleep deprivation. These results suggest that the effects of alcohol and sleep deprivation on performance are mediated – at least in part – by a common pathway that may involve the adenosinergic system in the brain

    Residents’ negative attitude towards air traffic is associated with impaired objective sleep quality

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    Objectives: Nocturnal aircraft noise induces sleep disturbances and is associated with impaired quality of life. The magnitude of physiological and psychological responses to noise varies among individuals. Stable individual vulnerabilities have been reported for aircraft noise induced awakenings. To date it is unknown, whether the subjective attitude towards air traffic and residents' sleep quality impact on each other. Methods: Seventy-four out of 81 investigated residents around Frankfurt Airport (Germany) rated their attitude towards air traffic (from 1 = negative to 5 = positive; negative attitude: score ≤ 2, N=28, mean age 44 ± 16 years; moderate to positive attitude: score > 3, N=46, mean age 44 ± 15 years) and evaluated its necessity (from 1 = not necessary to 5 = highly necessary; no to moderate necessity: score ≤ 3, N=22, mean age 45 ± 10 years; high necessity: score > 3, N=52, mean age 43 ± 17 years). In addition, polysomnographical recordings were obtained in residents' home environment. These investigations were part of the NORAH sleep study in 2012. Results: Significant impairments in sleep quality (prolonged sleep onset latency, increased wake after sleep onset, reduced sleep efficiency, and less deep sleep) were found for participants with a negative attitude towards air traffic. The judgement of no or moderate necessity of air traffic was associated with a significantly reduced deep sleep duration. Conclusions: Residents' subjective attitude towards air traffic and their objective sleep quality are related. Cause and effect in this relationship remain to be identified

    Improvising bags choreographies: Disturbing normative ways of doing research

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    Post-qualitative research-creation improvisations offer new possibilities to explore method/ology. In this article we question how bags, as seemingly mundane objects, work as ontologically lively matter – as active agencies – to choreograph human-nonhuman relations and heterogeneous materialities. Working from three questions – How might a bag become? What do bags do? What do bags enable and enact? – we discuss four research-creation improvisations and the insights they generated. The article maps how bags choreographies put affects, bodies and materialities into co-motional relations in order to disturb normative approaches to research both within conference sessions and through writing articles

    Coffee Effectively Attenuates Impaired Attention in ADORA2A C/C-Allele Carriers During Chronic Sleep Restriction

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    Many people consume coffee to attenuate increased sleepiness and impaired vigilance and attention due to insufficient sleep. We investigated in genetically caffeine sensitive individuals whether 'real world' coffee consumption during a simulated busy work week counteracts disabling consequences of chronically restricted sleep. We subjected homozygous C-allele carriers of ADORA2A (gene encoding adenosine A2A receptors) to 5 nights of only 5 h time-in-bed. We administered regular coffee (n = 12; 200 mg caffeine at breakfast and 100 mg caffeine after lunch) and decaffeinated coffee (n = 14) in double-blind fashion on all days following sleep restriction. At regular intervals 4 times each day, participants rated their sleepiness and performed the psychomotor vigilance test, the visual search task, and the visuo-spatial and letter n-back tasks. At bedtime, we quantified caffeine and the major caffeine metabolites paraxanthine, theobromine and theophylline in saliva. The 2 groups did not differ in age, body-mass-index, sex-ratio, chronotype and mood states. Subjective sleepiness increased in both groups across consecutive sleep restriction days and did not differ. By contrast, regular coffee counteracted the impact of repeated sleep loss on sustained and selective attention, as well as executive control when compared to decaffeinated coffee. The coffee induced benefits on different aspects of performance lasted for 4-5 days of insufficient sleep. All differences between the groups disappeared after the recovery night and the cessation of coffee administration. The data suggest that 'real world' coffee consumption can efficiently attenuate sleep restriction-induced impairments in vigilance and attention in genetically caffeine sensitive individuals. German Clinical Trial Registry: # DRSK00014379

    Disturbing the AcademicConferenceMachine: Post-qualitative re-turnings

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    Author 1: They say they want to disturb the AcademicConferenceMachine. Author 34: What is an AcademicConferenceMachine? Author 2: Please do not go in that direction. Ask, for example, what does an AcademicConferenceMachine do? Author 51: Ok, so what does it do? Author 6: AcademicConferenceMachines are becoming so regulated and standardized that they might lose the possibility to produce different knowledge and to produce knowledge differently. Author 227: Do you think they succeeded? Author 9999: I do not know

    Conferencing otherwise: a feminist new materialist writing experiment

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    This paper attempts to reconfigure hegemonic framings of ‘the academic conference’ and thereby offer a means to (re-)encounter the spatial, temporal and affective forces that conferences generate, differently. We are a geographically dispersed but multiply entangled group of academic researchers united by theoretical fault lines within our work that seek to ask what if (Haraway, 2016) and what else (Manning, 2016). This ‘what if’ and ‘what else’ thinking has manifested in experimental and subversive doings otherwise at a series of academic conferences. The storying practices presented in this paper were made possible by the vital materialism (Bennett, 2010) of a shared google.doc. It was within this virtual environment that we attempted to weave diffractive accounts of what conferencing otherwise produces. This writing experiment offers a series of speculative provocations and counter-provocations to ask what else does conferencing make possible. This article is an invitation to the reader to plunge in and wallow (Taylor, 2016) within the speculative accounts which ensue and to contemplate the possibilities of breaking free from sedimented ways of neoliberal conferencing

    Repeated caffeine intake suppresses cerebral grey matter responses to chronic sleep restriction in an A1 adenosine receptor-dependent manner: a double-blind randomized controlled study with PET-MRI

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    Evidence has shown that both sleep loss and daily caffeine intake can induce changes in grey matter (GM). Caffeine is frequently used to combat sleepiness and impaired performance caused by insufficient sleep. It is unclear (1) whether daily use of caffeine could prevent or exacerbate the GM alterations induced by 5‑day sleep restriction (i.e. chronic sleep restriction, CSR), and (2) whether the potential impact on GM plasticity depends on individual differences in the availability of adenosine receptors, which are involved in mediating effects of caffeine on sleep and waking function. Thirty‑six healthy adults participated in this double‑blind, randomized, controlled study (age = 28.9 ± 5.2 y/; F:M = 15:21; habitual level of caffeine intake < 450 mg; 29 homozygous C/C allele carriers of rs5751876 of ADORA2A, an A 2A adenosine receptor gene variant). Each participant underwent a 9‑day laboratory visit consisting of one adaptation day, 2 baseline days (BL), 5‑day sleep restriction (5 h time‑in‑bed), and a recovery day (REC) after an 8‑h sleep opportunity. Nineteen participants received 300 mg caffeine in coffee through the 5 days of CSR (CAFF group), while 17 matched participants received decaffeinated coffee (DECAF group). We examined GM changes on the 2nd BL Day, 5th CSR Day, and REC Day using magnetic resonance imaging and voxel‑based morphometry. Moreover, we used positron emission tomography with [ 18 F]‑CPFPX to quantify the baseline availability of A 1 adenosine receptors (A 1 R) and its relation to the GM plasticity. The results from the voxel‑wise multimodal whole‑brain analysis on the Jacobian‑modulated T1‑weighted images controlled for variances of cerebral blood flow indicated a significant interaction effect between caffeine and CSR in four brain regions: (a) right temporal‑occipital region, (b) right dorsomedial prefrontal cortex (DmPFC), (c) left dorsolateral prefrontal cortex (DLPFC), and (d) right thalamus. The post‑hoc analyses on the signal intensity of these GM clusters indicated that, compared to BL, GM on the CSR day was increased in the DECAF group in all clusters but decreased in the thalamus, DmPFC, and DLPFC in the CAFF group. Furthermore, lower baseline subcortical A 1 R availability predicted a larger GM reduction in the CAFF group after CSR of all brain regions except for the thalamus. In conclusion, our data suggest an adaptive GM upregulation after 5‑day CSR, while concomitant use of caffeine instead leads to a GM reduction. The lack of consistent association with individual A 1 R availability may suggest that CSR and caffeine affect thalamic GM plasticity predominantly by a different mechanism. Future studies on the role of adenosine A 2A receptors in CSR‑induced GM plasticity are warranted
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