202 research outputs found
Digitale GesprĂ€che in einer virtuellen Welt? Eine linguistische Analyse der kommunikativen Spezifika spanischer Freizeitchat-Kommunikation im Spannungsfeld von MĂŒndligkeit und Schriftlichkeit
Die Heidelberger Dissertation âDigitale GesprĂ€che in einer virtuellen Welt?â diskutiert die kommunikationstheoretische Verortung des spanischen Freizeitchat im Spannungsfeld von MĂŒndlichkeit und Schriftlichkeit. Um ein möglichst ganzheitliches Bild der getippten Kommunikation zu zeichnen, wird zunĂ€chst die Bedeutung des medialen Kontexts (d.h. des durch das Medium Computer generierten Offline- und Online-Kontextes) sowie der Chatprogramme beleuchtet. So ermöglicht es der Vergleich der Programme âInternet Relay Chatâ, âInstant Messaging-Systemâ und âWeb-Chatâ allgemeine Konstitutiva des Kommunikationsvollzuges zu identifizieren und von technologisch bedingten Unterschieden zu differenzieren. Weiter wird zwischen im beruflichen Kontext und im freizeitlichen Bereich eingesetzten Chat-Angeboten unterschieden, da sowohl die QuantitĂ€t als auch die ModalitĂ€t bestimmter Verfahren und Elemente in AbhĂ€ngigkeit vom Kommunikationsziel variieren. Diese Differenzierung ist besonders wichtig, da der GroĂteil der PhĂ€nomene, die hĂ€ufig als Hinweise zur Situierung von Chat-Kommunikation im Rahmen von MĂŒndlichkeit interpretiert werden (z. B. der hohe Anteil umgangssprachlicher Elemente oder die Verwendung von Emoticons), nur fĂŒr im Freizeitbereich angesiedelte Chats als charakteristisch gelten können. Um schlieĂlich die GradualitĂ€t dieser verschiedenen EinflĂŒsse auf die im Freizeit-Chat vollzogene Interaktion sowohl in Bezug auf die ModalitĂ€t des Kommunikations-vollzuges als auch auf sprachlicher Ebene bewerten zu können, wird die Klassifikation des Chats als Kommunikationsform oder kommunikative Gattung diskutiert und dieser in Anlehnung an BeiĂwenger 2007 als Kommunikationsform identifiziert, in deren Rahmen die kommunikative Gattung des Freizeit-Chats bereitgestellt wird. Im Anschluss wird die sprach- und kommunikationstheoretische Grundlage fĂŒr die Situierung des spanischen Freizeitchats im Spannungsfeld von MĂŒndlichkeit und Schriftlichkeit gelegt, indem MĂŒndlichkeit und Schriftlichkeit zunĂ€chst aus medial-extensionaler Perspektive beleuchtet werden, d.h. die in der aktuellen Forschungsliteratur auf dieser Basis der gesprochenen und geschriebenen Sprache zugesprochenen Merkmale kontrastiert und im Kontext der kommunikativen Gattung erörtert werden. In einem zweiten Schritt werden MĂŒndlichkeit und Schriftlichkeit aus einer von der Realisationsform der Sprache unabhĂ€ngigen Perspektive betrachtet, indem das von Peter Koch und Wulf Oesterreicher etablierte Modell kritisch diskutiert wird, das die respektiv charakteristischen Elemente auf prototypisch graduierende Weise bestimmt. In diesem Kontext wird auch die Anwendbarkeit der Konzepte Text, Diskurs und Paradiskurs auf die im Rahmen der Chat-Technologie vollzogene Kommunikation reflektiert und die in der aktuellen medienlinguistischen Forschung diskutierten VorschlĂ€ge zur kommunikationstheoretischen Verortung von computervermittelter Kommunikation im Spannungsfeld von MĂŒndlichkeit und Schriftlichkeit von Kattenbusch 2002, Berruto 2005, DĂŒrscheid 2003 betrachtet. Auch die von Ăgel und Hennig 2007 entwickelte Theorie des NĂ€he- und Distanzsprechens wird vorgestellt und im Hinblick auf ihre Anwendbarkeit auf Freizeit-Chat-Kommunikation beleuchtet. Auf dieser Basis wird nun ein durch DĂŒrscheid 2003 und Ăgel und Hennig 2007 inspiriertes Konzept der medial-extensionalen Bestimmung von MĂŒndlichkeit und Schriftlichkeit bei deren gleichzeitiger prototypisch-graduierender Differenzierung entwickelt und die Kommunikation im spanischen Freizeit-Chat Lycos als NĂ€hesprechen identifiziert, indem die durch die QualitĂ€t der kommunikativen NĂ€he ausgelösten sprachlichen Besonderheiten beschrieben und auf die sie bedingenden Dimensionen zurĂŒckgefĂŒhrt werden. Hierbei werden sowohl die durch das Medium im Sinne Koch/ Oesterreichers determinierten PhĂ€nomene als auch die weder durch die schriftliche Realisierung noch durch eine NĂ€he- oder Distanz-Dimension ausgelösten, jedoch durch eine Kommunikationsbedingung generierten Merkmale berĂŒcksichtigt und mit Hilfe von dem spanischen Freizeit-Chat Lycos entnommenen Sprachmaterial veranschaulicht. So lĂ€sst z. B. die Selbstwahrnehmung der Chatter als Sprecher oder Schreiber (d. h. die in Lycos Chat verwendete GesprĂ€chs- und Textmetaphorik) RĂŒckschlĂŒsse auf die Perzeption der besonderen QualitĂ€t der Schriftlichkeit durch die Teilnehmer zu, die der interaktiven Gestaltung der quasi-synchronen Kommunikation in einem gemeinsamen Kommunikationsraum durch die Verwendung von decir, contar, charlar, oĂr und escuchar Rechnung tragen, aber hier auch escribir und leer verwenden, was darauf hindeutet, dass die Charakteristika der Freizeit-Chat-Kommunikation in Lycos einerseits im Kontrast zu den Vorstellungen der Teilnehmer von prototypischer Schriftlichkeit stehen, sich die Teilnehmer andererseits jedoch ĂŒber deren Differenzen zur gesprochenen Sprache durchaus bewusst sind
The interplay between emotional arousal and memory processes â from large-scale to translational fMRI studies
Emotional arousal greatly impacts what we remember about an event and how well we remember it. This memory-modulating effect of arousal has been subject to intensive research for decades. In recent years, fMRI data has enabled increasing understanding how arousal and memory are integrated in the human brain. Since then, researchers have been striving to identify the brain regions involved in emotional memory processing and to elucidate how dysfunctional activation in certain neuronal circuits relates to psychiatric disorders. However, the majority of fMRI studies lack sufficient statistical power to produce robust results. In addition, the common use of group-level analyses based on contrasts, a rather insensitive method compared to analysis on an individual level, has, up to now, hampered the utility of fMRI findings for clinical routine.
The aim of the present thesis is to present new scientific advances in the relationship between emotional arousal and memory documented in two publications that used large-scale fMRI data from our lab in two different ways. The publication Loos et al. (2019) took an exploratory approach based on fMRI and behavioral data from more than 1â000 healthy young subjects. Applying multi-voxel pattern analysis, we identified a brain network which could be used, on the one hand, to predict an individualâs perceived arousal during encoding and, on the other hand, to predict episodic memory performance of an individual during later recognition. Both processes, perceived arousal and episodic memory, are heavily impaired in emotional memory-related diseases like anxiety disorders. Therefore, the reported network constitutes an important target for further research in patients with dysfunctional emotional memory.
The second publication, Loos et al. (submitted), used large-scale data to derive a hypothesis-driven research question which we tested in an independent fMRI study. Using a pictorial working memory (WM) task in subjects reporting fear of snakes, we could demonstrate that high compared to low WM load not only acutely decreased amygdala activity but also reduced perceived phobic fear and disgust towards snake pictures. Additional effective connectivity analysis revealed that the dlPFC, which is particularly engaged in WM tasks, exerted an inhibitory influence on the amygdala during high WM load conditions. The study intended to translate findings from basic research into a more clinical context and may inspire the development of new approaches for the treatment of anxiety disorders.
In sum, the thesis adds to the knowledge on the interplay between emotional arousal and episodic as well as working memory processes by providing robust and reproducible results. In addition, it highlights the importance of well-powered fMRI studies for the identification of neural mechanisms that improve diagnosis and treatment in clinical practice
Recognition memory performance can be estimated based on brain activation networks
Recognition memory is an essential ability for functioning in everyday life. Establishing robust brain networks linked to recognition memory performance can help to understand the neural basis of recognition memory itself and the interindividual differences in recognition memory performance.; We analysed behavioural and whole-brain fMRI data from 1'410 healthy young adults during the testing phase of a picture-recognition task. Using independent component analysis (ICA), we decomposed the fMRI contrast for previously seen vs. new (old-new) pictures into networks of brain activity. This was done in two independent samples (training sample: N = 645, replication sample: N = 665). Next, we investigated the relationship between the identified brain networks and interindividual differences in recognition memory performance by conducting a prediction analysis. We estimated the prediction accuracy in a third independent sample (test sample: N = 100).; We identified 12 robust and replicable brain networks using two independent samples. Based on the activity of those networks we could successfully estimate interindividual differences in recognition memory performance with high accuracy in a third independent sample (r = 0.5, p = 1.29 Ă 10; -07; ).; Given the robustness of the ICA decomposition as well as the high prediction estimate, the identified brain networks may be considered as potential biomarkers of recognition memory performance in healthy young adults and can be further investigated in the context of health and disease
Reengineering der Content-Erstellungsprozesse in Industrieunternehmen durch Content-Modellierung: Fallbeispiel
Human cerebellum and corticocerebellar connections involved in emotional memory enhancement
Emotional information is better remembered than neutral information. Extensive evidence indicates that the amygdala and its interactions with other cerebral regions play an important role in the memory-enhancing effect of emotional arousal. While the cerebellum has been found to be involved in fear conditioning, its role in emotional enhancement of episodic memory is less clear. To address this issue, we used a whole-brain functional MRI approach in 1,418 healthy participants. First, we identified clusters significantly activated during enhanced memory encoding of negative and positive emotional pictures. In addition to the well-known emotional memory-related cerebral regions, we identified a cluster in the cerebellum. We then used dynamic causal modeling and identified several cerebellar connections with increased connection strength corresponding to enhanced emotional memory, including one to a cluster covering the amygdala and hippocampus, and bidirectional connections with a cluster covering the anterior cingulate cortex. The present findings indicate that the cerebellum is an integral part of a network involved in emotional enhancement of episodic memory
A peripheral epigenetic signature of immune system genes is linked to neocortical thickness and memory
Increasing age is tightly linked to decreased thickness of the human neocortex. The biological mechanisms that mediate this effect are hitherto unknown. The DNA methylome, as part of the epigenome, contributes significantly to age-related phenotypic changes. Here, we identify an epigenetic signature that is associated with cortical thickness (P=3.86 Ă 10(-8)) and memory performance in 533 healthy young adults. The epigenetic effect on cortical thickness was replicated in a sample comprising 596 participants with major depressive disorder and healthy controls. The epigenetic signature mediates partially the effect of age on cortical thickness (P<0.001). A multilocus genetic score reflecting genetic variability of this signature is associated with memory performance (P=0.0003) in 3,346 young and elderly healthy adults. The genomic location of the contributing methylation sites points to the involvement of specific immune system genes. The decomposition of blood methylome-wide patterns bears considerable potential for the study of brain-related traits
ATRT-02. Neuropsychological function in infant atypical teratoid/rhabdoid tumor versus low-grade glioma survivors reflects tumor malignancy and multimodal treatment [Abstract]
BACKGROUND: Therapy of infants with brain tumors predisposes these patients to increased risks for cognitive sequelae, especially following radiotherapy. Neuropsychological outcome gains importance for those 40-60% of patients with an atypical teratoid/rhabdoid tumor (ATRT) who survive beyond 2 years. Still, reports on cognitive late-effects in children with ATRT are scarce compared to other pediatric brain tumor groups. We analyzed neuropsychological outcome for long-term ATRT-survivors registered in EU-RHAB and infant low-grade glioma (LGG) survivors from the SIOP-LGG 2004-study and LGG-registry. PATIENTS+METHODS: Age at diagnosis of both cohorts was 0-36 months. ATRT-patients (n=13) treated with up to 54Gy radiotherapy (median age 22 months (±7.1)) were evaluated with the âATRT-Neuropsychologyâ tool based on SIOPE-BTG QoS-Group recommendations at median 6.8 years (±2.8) after diagnosis. LGG-patients (n=15) treated without radiotherapy (4/15 with chemotherapy) were analyzed with the German âNeuropsychological-Basic-Diagnosticâ tool 5.2 years (±0.6) post-diagnosis. RESULTS: The ATRT- vs. LGG-cohorts were comparable for median age at diagnosis, sex-ratio and tumor-localization, though they differed slightly in median age at assessment (9.5/7.2 years (±2.5/1.1)). Results of age-appropriate tests showed increased impairments for ATRT-patients in fluid intelligence (FI) (p=.006, d=1.214) and in visual-spatial processing (VSP) (p<.001, d=2.233) compared to LGG-patients. The median for neuropsychological test results of ATRT-patients spanned from considerably below the normal to the lower normal range (median=65-90), while results of LGG-patients were mostly in the lower normal range (median=83-103). Results for psychomotor speed abilities (PMS) were distinctly below the norm for both patient groups (p=.002-.007). CONCLUSION: Infant ATRT- and LGG-patients develop significant impairments in PMS abilities following multimodal treatment. Long-term survivors of ATRT suffer from additional FI and VSP deficits. Our data suggest that high malignancy requiring multimodal treatment determines the inferior cognitive outcome for the ATRT-cohort. Long-term neuropsychological monitoring (and treatment options) should be implemented as standard of care in ATRT- and LGG-trials
Identification of Two Distinct Working Memory-Related Brain Networks in Healthy Young Adults
Working memory (WM) is an important cognitive domain for everyday life functioning and is often disturbed in neuropsychiatric disorders. Functional magnetic resonance imaging (fMRI) studies in humans show that distributed brain areas typically described as fronto-parietal regions are implicated in WM tasks. Based on data from a large sample of healthy young adults (; N; = 1369), we applied independent component analysis (ICA) to the WM-fMRI signal and identified two distinct networks that were relevant for differences in individual WM task performance. A parietally-centered network was particularly relevant for individual differences in task measures related to WM performance ("WM dependent") and a frontally-centered network was relevant for differences in attention-dependent task performance. Importantly, frontal areas that are typically considered as key regions for WM were either involved in both WM-dependent and attention-dependent performance, or in attention-dependent performance only. The networks identified here are provided as publicly available datasets. These networks can be applied in future studies to derive a low-dimensional representation of the overall WM brain activation
Two New Loci for Body-Weight Regulation Identified in a Joint Analysis of Genome-Wide Association Studies for Early-Onset Extreme Obesity in French and German Study Groups
Meta-analyses of population-based genome-wide association studies (GWAS) in adults have recently led to the detection of new genetic loci for obesity. Here we aimed to discover additional obesity loci in extremely obese children and adolescents. We also investigated if these results generalize by estimating the effects of these obesity loci in adults and in population-based samples including both children and adults. We jointly analysed two GWAS of 2,258 individuals and followed-up the best, according to lowest p-values, 44 single nucleotide polymorphisms (SNP) from 21 genomic regions in 3,141 individuals. After this DISCOVERY step, we explored if the findings derived from the extremely obese children and adolescents (10 SNPs from 5 genomic regions) generalized to (i) the population level and (ii) to adults by genotyping another 31,182 individuals (GENERALIZATION step). Apart from previously identified FTO, MC4R, and TMEM18, we detected two new loci for obesity: one in SDCCAG8 (serologically defined colon cancer antigen 8 gene; p = 1.85610 x 10(-8) in the DISCOVERY step) and one between TNKS (tankyrase, TRF1-interacting ankyrin-related ADP-ribose polymerase gene) and MSRA (methionine sulfoxide reductase A gene; p = 4.84 x 10(-7)), the latter finding being limited to children and adolescents as demonstrated in the GENERALIZATION step. The odds ratios for early-onset obesity were estimated at similar to 1.10 per risk allele for both loci. Interestingly, the TNKS/MSRA locus has recently been found to be associated with adult waist circumference. In summary, we have completed a meta-analysis of two GWAS which both focus on extremely obese children and adolescents and replicated our findings in a large followed-up data set. We observed that genetic variants in or near FTO, MC4R, TMEM18, SDCCAG8, and TNKS/MSRA were robustly associated with early-onset obesity. We conclude that the currently known major common variants related to obesity overlap to a substantial degree between children and adults
Parent-of-origin-specific allelic associations among 106 genomic loci for age at menarche.
Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (Pâ<â5âĂâ10(-8)) for 123 signals at 106 genomic loci associated with age at menarche. Many loci were associated with other pubertal traits in both sexes, and there was substantial overlap with genes implicated in body mass index and various diseases, including rare disorders of puberty. Menarche signals were enriched in imprinted regions, with three loci (DLK1-WDR25, MKRN3-MAGEL2 and KCNK9) demonstrating parent-of-origin-specific associations concordant with known parental expression patterns. Pathway analyses implicated nuclear hormone receptors, particularly retinoic acid and Îł-aminobutyric acid-B2 receptor signalling, among novel mechanisms that regulate pubertal timing in humans. Our findings suggest a genetic architecture involving at least hundreds of common variants in the coordinated timing of the pubertal transition
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