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OA Förderung 2023 The task-switching paradigm is deemed a measure of cognitive flexibility. Previous research has demonstrated that individual differences in task-switch costs are moderately inversely related to cognitive ability. However, current theories emphasize multiple component processes of task switching, such as task-set preparation and task-set inertia. The relations of task-switching processes with cognitive ability were investigated in the current study. Participants completed a task-switching paradigm with geometric forms and a visuospatial working memory capacity (WMC) task. The task-switch effect was decomposed with the diffusion model. Effects of task-switching and response congruency were estimated as latent differences using structural equation modeling. Their magnitudes and relations with visuospatial WMC were investigated. Effects in the means of parameter estimates replicated previous findings, namely increased non-decision time in task- switch trials. Further, task switches and response incongruency had independent effects on drift rates, reflecting their differential effects on task readiness. Findings obtained with the figural tasks employed in this study revealed that WMC was inversely related to the task-switch effect in non- decision time. Relations with drift rates were inconsistent. Finally, WMC was moderately inversely related to response caution. These findings suggest that more able participants either needed less time for task-set preparation or that they invested less time for task-set preparation.

Traumatic brain injury (TBI) causes the release of danger-associated molecular patterns (DAMP) from damaged or dead cells, which contribute to secondary brain damage after TBI. Cell-free DNA (cfDNA) is a DAMP known to cause disruption of the blood–brain barrier (BBB), promote procoagulant processes, brain edema, and neuroinflammation. This study tested the hypothesis that administration of deoxyribonuclease-I (DNase-I) has a beneficial effect after TBI. Mice (n = 84) were subjected to controlled cortical impact (CCI) and posttraumatic intraperitoneal injections of low dose (LD) or high dose (HD) of DNase-I or vehicle solution at 30 min and 12 h after CCI. LD was most effective to reduce lesion volume (p = 0.003), brain water content (p p = 0.019) 1 day post-injury (dpi). At 6 h post injury LD-treated animals showed less cleavage of fibrin (p = 0.0014), and enhanced perfusion as assessed by micro-computer-tomography (p = 0.027). At 5 dpi the number of Iba1-positive cells (p = 0.037) were reduced, but the number of CD45-positive cells, motoric function and brain lesion volume was not different. Posttraumatic-treatment with DNase-I therefore stabilizes the BBB, reduces the formation of brain edema, immune response, and delays secondary brain damage. DNase-I might be a new approach to extend the treatment window after TBI.

Hintergrund: Sprechen ist ein essenzieller Teil der Kommunikation und hat damit eine hohe Relevanz für die Partizipation, Teilhabe und die Lebensqualität. Dysarthrien, als häufigste Form einer neurologisch bedingten Sprechstörung, führen dazu, dass Betroffene entweder gar nicht oder nur erschwert zu verstehen sind. Eine qualitativ hochwertige Dysarthriediagnostik und -therapie erhalten daher in der Logopädie eine besondere Bedeutung. Methode: Es wurde eine systematische Literaturrecherche zu RCTs und Leitlinien mit dem Ziel durchgeführt, evidenzbasierte und aktuelle Empfehlungen für die Dysarthriediagnostik und -therapie zu identifizieren. Die Recherche schloss daher nur Evidenzen ein, die nicht älter als fünf Jahre sind. Die Qualität der gefundenen RCTs wurde mit Hilfe der CASPCheckliste bewertet. Ergebnisse: Es wurden drei RCTs und acht Leitlinien in die Auswertung eingeschlossen. Allgemein wird eine sprachtherapeutische Behandlung bei Dysarthrie empfohlen. Dabei ist eine therapeutische Anpassung an den individuellen Bedarf der Betroffenen notwendig. Der Einsatz nicht-sprachlicher oralmotorischer Bewegungen wird nicht empfohlen. Hingegen sollen Kommunikationshilfen wie die technisch unterstützte Kommunikation bei geringer Verständlichkeit in Betracht gezogen werden. Diskussion: Es liegen nur wenige Wirksamkeitsnachweise von angemessener Qualität für die Behandlung von Dysarthrien vor. Daher beinhalten die Leitlinien nur allgemein gehaltene Empfehlungen, aus denen kaum konkrete Handlungshilfen für die Praxis abgeleitet werden können. In den Empfehlungen der Leitlinien werden darüber hinaus die Störungsbilder Dysarthrie und Aphasie nicht immer konsequent und klar voneinander getrennt betrachtet. Schlussfolgerung: Um evidenzbasierte Empfehlungen für die Dysarthriediagnostik und -therapie geben zu können, bedarf es weiterer Forschung. Wünschenswert wäre auch mehr Diversität bei der Untersuchung der Behandlungsmethoden. Abstract Background: Speaking is an essential part of communication and therefore highly relevant for participation and quality of life. Dysarthrias are the most common form of neurologically induced speech disorders which means that those affected either cannot be understood at all or only with difficulty. Highquality dysarthria diagnosis and therapy therefore have a high priority in speech therapy. Methods: A systematic literature search for RCTs and guidelines was conducted with the aims of identifying evidence-based and current recommendations for dysarthria diagnosis and therapy. Thus, the search included only evidence that was not older than five years. The quality of the RCTs found was assessed using the CASP checklist. Results: Three RCTs and eight guidelines were included in the analysis. In general, speech therapy treatment is recommended for dysarthria. Therapeutic adaptation to the individual needs of the affected person is necessary. The use of non-linguistic oral-motor movements is not recommended. On the other hand, communication aids such as technology-assisted communication should be considered when intelligibility is low. Discussion: Although dysarthria often occurs as a result of stroke and neurodegenerative diseases, there is little evidence of efficacy of adequate quality for the treatment of dysarthria. As a result, guidelines only contain generalized recommendations that are unlikely to provide concrete guidance for practice. In the guidelines’ recommendations, the disorders dysarthria and aphasia are not consistently and clearly separated from each other. Conclusion: Further research is needed to make evidence-based recommendations for dysarthria diagnosis and treatment. Also, more diversity in the study of treatment methods would be desirable.

Cerebral inflammation with invasion of neutrophils and lymphocytes is a crucial factor in the process of secondary brain damage after traumatic brain injury (TBI). In TBI the intrinsic renin-angiotensin system is an important mediator of cerebral inflammation, as inhibition of the angiotensin II receptor type 1 (AT1) reduces secondary brain damage and the invasion of neutrophil granulocytes into injured cerebral tissue. The present study investigated the role of immune cells in AT1 inhibition-mediated neuroprotection after experimental TBI. In four different cohorts, male mice were studied to examine effects of neutropenia (anti-Ly6G antibody mediated neutrophil depletion; C57BL/6) or lymphopenia (RAG1 deficiency, RAG1-/-) alone, or in combination with candesartan-mediated AT1 inhibition. The present results demonstrate that reduction of neutrophils (neutrophil depletion in wild type mice) and of lymphocytes (RAG1-/-) as well as AT1 inhibition in (control antibody treated) wild type and RAG1-/- mice reduce brain damage and neuroinflammation after TBI compared to control groups, while in neutropenic mice, candesartan had no effect. However, AT1 inhibition was neuroprotective in RAG1-/- mice, but not in neutropenic mice. Therefore, the results indicate that AT1 inhibition mediated neuroprotection may be exerted by anti-inflammatory effects on neutrophils, with a subsequent reduction of neutrophil invasion.

ZusammenfassungEin 3‑jähriges Mädchen wird in der pädiatrischen Stoffwechselambulanz vorgestellt, da seit einigen Monaten im Rahmen der Sauberkeitsentwicklung dunkle Urinverfärbungen aufgefallen sind. Die ausführliche Abklärung bezüglich einer Porphyrie und Hämaturie führte nicht zur Diagnosestellung. Die beim Kinderarzt abgegebenen Urinproben waren jeweils unauffällig. Im Rahmen der spezifischen Diagnostik zeigten sich eine erhöhte Homogentisatausscheidung im Urin und damit die Diagnosestellung einer Alkaptonurie. Es wurde eine spezifische Therapie eingeleitet, um Gelenkschädigungen durch pathologische Ablagerungen zu reduzieren. Die weitere Prognose bleibt unklar.

The time on task (ToT) effect describes the relationship of the time spent on a cognitive task and the probability of successful task completion. The effect has been shown to vary in size and direction across tests and even within tests, depending on the test taker and item characteristics. Specifically, investing more time has a positive effect on response accuracy for difficult items and low ability test-takers, but a negative effect for easy items and high ability test-takers. The present study sought to test the replicability of this result pattern of the ToT effect across samples independently drawn from the same populations of persons and items. Furthermore, its generalizability was tested in terms of differential correlations across ability tests. To this end, ToT effects were estimated for three different reasoning tests and one test measuring natural sciences knowledge in 10 comparable subsamples with a total N = 2640. Results for the subsamples were highly similar, demonstrating that ToT effects are estimated with sufficient reliability. Generally, faster answers tended to be more accurate, suggesting a relatively effortless processing style. However, with increasing item difficulty and decreasing person ability, the effect flipped to the opposite direction, i.e., higher accuracy with longer processing times. The within-task moderation of the ToT effect can be reconciled with an account on effortful processing or cognitive load. By contrast, the generalizability of the ToT effect across different tests was only moderate. Cross-test relations were stronger in relative terms if performance in the respective tasks was more strongly related. This suggests that individual differences in the ToT effect depend on test characteristics such as their reliabilities but also similarities and differences of their processing requirements.

The electric quadrupole moment of $^{49}$Sc was measured by collinear laser spectroscopy at CERN-ISOLDE to be $Q_{\rm s}=-0.159(8)$ $e$b, and a nearly tenfold improvement in precision was reached for the electromagnetic moments of $^{47,49}$Sc. The single-particle behavior and nucleon-nucleon correlations are investigated with the electromagnetic moments of $Z=21$ isotopes and $N=28$ isotones as valence neutrons and protons fill the distinctive $0f_{7/2}$ orbit, respectively, located between magic numbers, 20 and 28. The experimental data are interpreted with shell-model calculations using an effective interaction, and ab-initio valence-space in-medium similarity renormalization group calculations based on chiral interactions. These results highlight the sensitivity of nuclear electromagnetic moments to different types of nucleon-nucleon correlations, and establish an important benchmark for further developments of theoretical calculations., Comment: Accepted by Physics Letters B (2022)

Traumatic brain injury (TBI) involves primary mechanical damage and delayed secondary damage caused by vascular dysfunction and neuroinflammation. Intracellular components released into the parenchyma and systemic circulation, termed danger-associated molecular patterns (DAMPs), are major drivers of vascular dysfunction and neuroinflammation. These DAMPs include cell-free RNAs (cfRNAs), which damage the blood–brain barrier (BBB), thereby promoting edema, procoagulatory processes, and infiltration of inflammatory cells. We tested the hypothesis that intraperitoneal injection of Ribonuclease-1 (RNase1, two doses of 20, 60, or 180 µg/kg) at 30 min and 12h after controlled-cortical-impact (CCI) can reduce secondary lesion expansion compared to vehicle treatment 24h and 120h post-CCI. The lowest total dose (40 µg/kg) was most effective at reducing lesion volume (−31% RNase 40µg/kg vs. vehicle), brain water accumulation (−5.5%), and loss of BBB integrity (−21.6%) at 24h post-CCI. RNase1 also reduced perilesional leukocyte recruitment (−53.3%) and microglial activation (−18.3%) at 120h post-CCI, but there was no difference in lesion volume at this time and no functional benefit. Treatment with RNase1 in the early phase following TBI stabilizes the BBB and impedes leukocyte immigration, thereby suppressing neuroinflammation. RNase1-treatment may be a novel approach to delay brain injury to extend the window for treatment opportunities after TBI.