29 research outputs found

    Of monkeys and men:Impatience in perceptual decision-making

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    For decades sequential sampling models have successfully accounted for human and monkey decision-making, relying on the standard assumption that decision makers maintain a pre-set decision standard throughout the decision process. Based on the theoretical argument of reward rate maximization, some authors have recently suggested that decision makers become increasingly impatient as time passes and therefore lower their decision standard. Indeed, a number of studies show that computational models with an impatience component provide a good fit to human and monkey decision behavior. However, many of these studies lack quantitative model comparisons and systematic manipulations of rewards. Moreover, the often-cited evidence from single-cell recordings is not unequivocal and complimentary data from human subjects is largely missing. We conclude that, despite some enthusiastic calls for the abandonment of the standard model, the idea of an impatience component has yet to be fully established; we suggest a number of recently developed tools that will help bring the debate to a conclusive settlement

    Neural correlates of evidence accumulation during value-based decisions revealed via simultaneous EEG-fMRI

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    Current computational accounts posit that, in simple binary choices, humans accumulate evidence in favour of the different alternatives before committing to a decision. Neural correlates of this accumulating activity have been found during perceptual decisions in parietal and prefrontal cortex; however the source of such activity in value-based choices remains unknown. Here we use simultaneous EEG–fMRI and computational modelling to identify EEG signals reflecting an accumulation process and demonstrate that the within- and across-trial variability in these signals explains fMRI responses in posterior-medial frontal cortex. Consistent with its role in integrating the evidence prior to reaching a decision, this region also exhibits task-dependent coupling with the ventromedial prefrontal cortex and the striatum, brain areas known to encode the subjective value of the decision alternatives. These results further endorse the proposition of an evidence accumulation process during value-based decisions in humans and implicate the posterior-medial frontal cortex in this process

    Concrete knowledge improvement in sub-Saharan Africa

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    The building situation in Africa is overwhelmed with high-priced materials and lack of adequate concrete technology, which provides a challenge in the concrete industry. Worldwide, cement and concrete experts are at the cutting-edge to sustainable, green and healthy but nonetheless highperformance concrete, which is more sustainable and safer than traditional methods of construction with clay and wood. Since concrete in Africa is rather a new construction material, this sustainability experience can offer the continent a unique opportunity to begin a constantly growing building sector with the newest state-of-the-art technology. This can be achieved without subordinating to existing standards by establishing a sustainable "African concrete technology". The major challenge for most sub-Saharan countries is the deficiency of experts, which would be required to establish such state-of-the-art technology. Based on the examples of two African-European scientific networks - SPIN and LightSHIP - this paper presents possible solution strategies for the establishment of a scientific cooperation between Europe and Africa, with links to policy making bodies that can help accelerate the progress of cement and concrete industries in Africa

    Comparison of First-Line Radiosurgery for Small-Cell and Non-Small Cell Lung Cancer Brain Metastases (Cross-FIRE)

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    INTRODUCTION Historical reservations regarding radiosurgery (SRS) for small-cell-lung-cancer (SCLC) brain metastases (BrM) include concerns for short-interval/diffuse CNS-progression, poor prognoses, and increased neurological mortality specific to SCLC histology. We compared SRS outcomes for SCLC and non-small-cell-lung-cancer (NSCLC) where SRS is well established. METHODS Multicenter first-line SRS outcomes for SCLC and NSCLC from 2000-2022 were retrospectively collected (N=892-SCLC/N=4,785-NSCLC). Data from the prospective JLGK0901 SRS trial were analyzed as a comparison cohort (N=98-SCLC/N=794-NSCLC). OS and CNS-progression were analyzed using Cox-Proportional-Hazard and Fine-Gray models, respectively, with multivariable (MV) adjustment (including age/sex/performance-status/year/extracranial disease/BrM-number/BrM-volume). Mutation-stratified analyses were performed in propensity score-matched (PSM) retrospective cohorts of EGFR/ALK-positive-NSCLC, mutation-negative-NSCLC, and SCLC. RESULTS OS was superior with NSCLC over SCLC in the retrospective dataset (median-OS, 10.5 vs 8.6 months, MV-p<0.001) and JLGK0901. Hazard estimates for first CNS-progression favoring NSCLC were similar in both datasets but reached significance in the retrospective dataset only (MV-HR:0.82 [95%-CI:0.73-0.92], p=0.001). In the PSM cohorts, there were continued OS advantages for NSCLC (median-OS, 23.7 [EGFR/ALK-positive-NSCLC] vs 13.6 [mutation-negative-NSCLC] vs 10.4 months [SCLC], pairwise-p-values<0.001), but no significant differences in CNS-progression. Neurological mortality and number of lesions at CNS-progression were similar for NSCLC and SCLC patients. Leptomeningeal-progression was increased in NSCLC patients in the retrospective dataset only (MV-HR:1.61 [95%-CI:1.14-2.26], p=0.007). CONCLUSION After SRS, SCLC was associated with shorter OS compared to NSCLC. CNS progression occurred earlier in SCLC overall but was similar in patients matched on baseline characteristics. Neurological mortality, lesions at CNS-progression, and leptomeningeal-progression were comparable. These findings may better inform clinical decision-making for SCLC patients
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