In dieser Studie untersuchten wir den Mechanismus und die neuronalen Strukturen, die an der auditorischen Filterung bedeutungsvoller Reize während des Schlafs beteiligt sind. Zunächst entwickelten wir ein Verhaltensparadigma, bei dem Geräusche in einer bedeutungsabhängigen Weise Veränderungen in schlafassoziierten Oszillationen hervorrufen. Interessanterweise traten diese Störungen bereits bei niedrigen Schallintensitäten während des NREM- und REM-Schlafs auf, was die starke Einflussnahme bedeutungsvoller Reize auf die Schlafdynamik betont. Darüber hinaus unterstrich unsere Analyse von Verallgemeinerungsseffekten unter Verwendung verschiedener neutraler Klangreize die breite Wirkung bedeutungsvoller Klänge auf das EEG, unabhängig von der Unterscheidbarkeit der Geräusche. Wir erweiterten unserer Verhaltensparadigma auf kopffixierte Tiere und konnten NREM- und REM-Schlafphasen nach einer längeren Habituation nachweisen. Bemerkenswerterweise waren unsere Befunde für kopffixierte im Vergleich zu sich frei bewegenden Tieren sehr ähnlich, da das konditionierte Geräusch im Vergleich zu neutralen Reizen einen erhöhten Einfluss auf schlafassoziierte Oszillationen hatte. Schließlich untersuchten wir den neuronalen Zusammenhang der auditiven Verarbeitung während des Wachzustands und des Schlafs, wobei wir uns auf den Colliculus Inferior (CI) konzentrierten. Unsere Analysen enthüllten unterschiedliche neuronale Reaktionen auf bedeutungsvolle und neutrale Reize, wobei der bedeutungsvolle Reiz während des Wachzustands, aber nicht während des NREM-Schlafs, höhere Feuerraten auslöste, was auf eine zustandsabhängige neuronale Verarbeitung hinweist. Darüber hinaus zeigten unsere Untersuchungen eine verstärkte zeitliche Musterbildung als Reaktion auf den bedeutungsvollen Reiz während des NREM-Schlafs, was auf eine Rolle des CI bei der Kodierung bedeutungsvoller auditorischer Reize während des Schlafs hindeutet. Insgesamt liefert unsere Studie überzeugende Belege dafür, dass die Bedeutung eines Geräuschs signifikanten Einfluss auf schlafassoziierte Oszillationen sowie zeitliche Muster der neuronalen Aktivität im IC hat. / In this study, we delved into the mechanism and neural structures involved in the auditory gating of meaningful stimuli during sleep. First, we developed a behavioural paradigm in which sounds elicit changes in sleep-associated oscillations in a meaning-dependent manner. Interestingly, these disruptions occurred even at relatively low sound intensities during NREM and REM sleep, highlighting the potent influence of meaningful stimuli on sleep dynamics. Additionally, our exploration of generalization effects using various neutral sound stimuli underlined the broad influence of meaningful sounds on NREM EEG patterns, independent of sound discriminability. We extended our investigation to head-fixed animals, confirming their ability to achieve NREM and REM sleep phases following a prolonged habituation period. Notably, our findings were very similar for head-fixed compared to freely moving animals since the conditioned sound had increased influence on sleep-associated oscillations, compared to neutral stimuli. Finally, we studied the neural correlates of auditory processing during wakefulness and sleep, focusing on the inferior colliculus (IC). Our analyses revealed differential neuronal responses to meaningful and neutral stimuli, with the conditioned sound eliciting higher firing rates during wakefulness but not during NREM sleep, indicating state-dependent neural processing. Furthermore, our investigations unveiled enhanced temporal patterning in response to the conditioned sound during NREM sleep, suggesting a role of the IC in encoding meaningful auditory stimuli during sleep. Overall, our study provides compelling evidence that the meaning of a sound significantly influences sleep-associated oscillations as well as temporal patterning of neural activity in the IC.

Diese vorliegende Dissertation nutzt Koregistrierung von EEG und Eye-Tracking um neuronale Korrelate der Wortverarbeitung beim natürlichen Lesen zu untersuchen. EKP-Forschung hat unser Verständnis der Wortverarbeitung stark geprägt. Jedoch wird Lesen in EKP-Experimenten üblicherweise im unnatürlichen RSVP Paradigma untersucht. Der Blickbewegungsforschung verdanken wir viele Erkenntnisse über die Koordination von Sprachverarbeitung und Blickbewegungsplanung, allerdings nur auf der Verhaltensebene. Drei Leseexperimente in dieser Arbeit untersuchten a) foveale und parafoveale Wortverarbeitung, b) Wortschwierigkeit in Form von Wortfrequenzeffekten und c) den Einfluss von Blickbewegungen. Ein viertes Experiment untersuchte die Generalisierbarkeit parafovealer Vorverarbeitungs-Effekte (Preview-Effekte), indem diese mit chinesischen Sätzen repliziert wurden. Die Ergebnisse zeigten einen reliablen Effekt parafovealer Vorverarbeitung auf neuronale Korrelate der fovealen Worterkennung in Form eines frühen Effekts auf der N1 Komponente. Interaktionen zwischen dem Preview-Effekt und Wortfrequenz zeigten Wechselwirkungen der Verarbeitung aufeinanderfolgender Worte im fovealen und parafovealen Blickfeld. Preview-Effekte waren schwächer nach Worten mit niedriger Frequenz, was zeigt, wie komplexe foveale Wortverarbeitung Resourcen für parafoveale Information bindet. Andererseits beeinflusste parafoveale Verarbeitung auch die foveale Verarbeitung: Erstens durch den oben beschriebenen Preview-Effekt, zweitens durch eine Verlangsamung der Wortverarbeitungsrate nach schweren Vorschaubedingungen. Außerdem zeigten sich foveale Wortfrequenzeffekte früher nach valider parafovealer Wortvorschau. Der Preview-Effekt war stärker, wenn Blickbewegungen ausgeführt werden mussten. Der Grund hierfür sind verdeckte Aufmerksamkeitsverschiebungen vor einer Sakkade. (EKP-)Forschung zur visuellen Wortverarbeitung sollte zukünftig Blickbewegungen und parafoveale Vorverarbeitung berücksichtigen. / The current dissertation uses co-registration of EEG with eye tracking to study the brain-electric correlates of word processing under natural reading circumstances. ERP research has advanced our understanding of the neuronal mechanisms of word processing greatly but traditionally used the RSVP paradigm that is not ecologically valid. Eye tracking research has greatly advanced our understanding of the coordination of linguistic processing with eye movement execution but provides only indirect insight into the actual brain processes during reading. Three reading experiments were conducted to study a) foveal and parafoveal processing, b) word processing in the form of frequency effects, and c) the impact of eye movement planning and execution on a neuronal as well as behavioral level. A fourth experiment tested the generalizability of the preview effects by replicating preview effects in Chinese sentence reading. Results show a robust effect of parafoveal preview on brain-electric correlates of foveal word recognition in the form of an early effect on the N1 component. The preview effect interacted with word frequency in different ways, revealing interactions between the processing of subsequent words in parafoveal and foveal vision. Preview effects were smaller after low frequency words, showing that parafoveal processing is reduced if foveal processing is complex. Also, parafoveal processing also affected foveal processing: Firstly, by providing preview benefit as described above and secondly, by slowing processing rates after a difficult preview (delayed POF effects). Lastly, foveal word frequency effects were found earlier if valid parafoveal preview had been provided. Preview effects were much stronger if eye movements had to be executed, which is most likely due to pre-saccadic attention shifts. Results show the shortcomings of traditional ERP studies and suggest that research on visual word recognition needs to consider eye movements and parafoveal processing.

Overweight, a common health condition in adolescence, has been linked with difficulties in emotional processing. This study investigates associations between emotional processing, conceptualised through the model of Emotional Openness (EO), problematic eating behaviours, including Eating in the Absence of Hunger and disinhibited eating, and overweight in adolescents. Several self-report instruments were completed by 160 youngsters (mean age: 14.36 ± 0.61 years) from the community, including 39 overweight and obese adolescents (24.5%). In girls, bootstrap analyses supported a mediating effect of restrained eating on the relation between three EO dimensions and body mass index percentile, in particular the communication of emotions, the cognitive-conceptual representation of emotions, and the perception of bodily indicator of emotions. No mediating effect was found in boys. These results have important implications for psychological weight management interventions, as they underline the relevance of work on emotional processing in order to reduce problematic eating behaviours.

Die vorliegende Arbeit beschäftigt sich mit der Fragestellung, ob die Frühgeburtlichkeit eine Auswirkung auf den Spracherwerb im ersten Lebensjahr hat. Insbesondere wurde der Frage nachgegangen, ob sich die Verarbeitung der rhythmisch-prosodischen Eigenschaften von Sprache im ersten Lebensjahr und deren weitere Ausnutzung für die Entwicklung des Lexikons bei sehr untergewichtigen Deutsch lernenden Frühgeborenen im Vergleich zu Reifgeborenen unterscheidet. Die besondere Spracherwerbssituation Frühgeborener liefert weitere Erkenntnisse bezüglich der Frage, inwieweit der frühe Spracherwerb durch prädeterminierte reifungsbedingte Mechanismen und Abläufe bestimmt wird und inwieweit dessen Verlauf und die relevanten Erwerbsmechanismen durch individuelle erfahrungsabhängige Faktoren beeinflusst werden. Damit liefern die Ergebnisse auch einen weiteren Beitrag zur Nature-Nurture-Diskussion. / This research addresses the question if and how premature birth effects language acquisition during the first year of life. In particular the study focus on whether prosodic processing of language and the utilization of this knowledge for the acquisition of the lexicon during the fist year of life differs between German learning very low birth weight infants and term born infants. The specific exposure and postnatal situation of premature infants provide insights on the determination of early language acquisition and processes, and on the determination of language acquisition and its relevant mechanisms by individual experience. The results contribute to the nature-nurture discussion.

We present an algorithm for deciding whether an arbitrary proper probabilistic context-free grammar is consistent, i.e., whether the probability that a derivation terminates is one. Our procedure has time complexity $\\\\mathcal O(n^3)$ in the unit-cost model of computation. Moreover, we develop a novel characterization of consistent probabilistic context-free grammars. A simple corollary of our result is that training methods for probabilistic context-free grammars that are based on maximum-likelihood estimation always yield consistent grammars.

No description available.

No description available.

Humboldt-Universiẗat, Diss.--Berlin.

Habituation is a filter that optimizes the processing of information by our brain in all sensory modalities. It results in an unconscious reduced responsiveness to continuous or repetitive stimulation. In olfaction, the main question is whether habituation works the same way for any odorant or whether we habituate differently to each odorant? In particular, whether chemical, physical or perceptual cues can limit or increase habituation. To test this, the odour intensity of 32 odorants differing in physicochemical characteristics was rated by 58 participants continuously during 120s. Each odorant was delivered at a constant concentration. Results showed odorants differed significantly in habituation, highlighting the multifactoriality of habituation. Additionally habituation was predicted from 15 physico-chemical and perceptual characteristics of the odorants. The analysis highlighted the importance of trigeminality which is highly correlated to intensity and pleasantness. The vapour pressure, the molecular weight, the Odor Activity Value (OAV) and the number of double bonds mostly contributed to the modulation of habituation. Moreover, length of the carbon chain, number of conformers and hydrophobicity contributed to a lesser extent to the modulation of habituation. These results highlight new principles involved in the fundamental process of habituation, notably trigeminality and the physicochemical characteristics associated.

Background: Based on the assumptions that depersonalization symptoms are relevant for test anxiety maintenance, we examined their frequency, psychological predictors, association with anxiety symptoms, and association with test performance. Sampling and Methods: In Study 1, 203 students rated their test anxiety severity and depersonalization in their last oral examination. In Study 2, we assessed test anxiety 1 week before an oral examination, depersonalization, safety behaviors, self-focused attention, and negative appraisals of depersonalization directly after the examination, and post-event processing 1 week later among 67 students. Results: In Study 1, 47.3% reported at least one moderate depersonalization symptom. In Study 2, test anxiety and negative appraisals of depersonalization significantly predicted depersonalization. Depersonalization was linked to a higher intensity of safety behaviors and post-event processing but not to self-focused attention. It was not related to performance. Conclusion: Results are limited by the non-random sampling and the small sample size of Study 2. However, by showing that depersonalization contributes to the processes the maintenance of test anxiety, the findings confirm that depersonalization – normally understood as an adaptive mechanism to cope with stressful events – can become maladaptive.