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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Entwicklung einer Methode zur Identifikation dreidimensionaler Blickbewegungen in realer und virtueller Umgebung

Weber, Sascha 07 July 2016 (has links)
Das Verständnis über visuelle Aufmerksamkeitsprozesse ist nicht nur für die Kognitionsforschung von großem Interesse. Auch in alltäglichen Bereichen des Lebens stellt sich die Frage, wie wir unsere Umwelt in unterschiedlichen Situationen visuell wahrnehmen. Entsprechende Untersuchungen können in realen Szenarien und aufgrund neuer innovativer 3D-Verfahren auch in Umgebungen der virtuellen Realität (VR) durchgeführt werden. Zur Erforschung von Aufmerksamkeitsprozessen wird unter anderem die Methode der Blickbewegungsmessung (Eyetracking) angewandt, da das Sehen für uns Menschen die wichtigste Sinnesmodalität darstellt. Herkömmliche Blickbewegungsmessungen beziehen sich allerdings überwiegend auf zweidimensionale Messebenen, wie Bildschirm, Leinwand oder Szenevideo. Die vorliegende Arbeit stellt eine Methode vor, mit der dreidimensionale Blickorte und Blickbewegungen sowohl in einer realen als auch in einer stereoskopisch projizierten VR-Umgebung anhand moderner Eyetracking-Technologien bestimmt werden können. Dafür wurde zunächst in Studie I geprüft, ob die Blickbewegungsmessung durch die für eine stereoskopische Bildtrennung notwendigen 3D-Brillen hindurch möglich ist und inwieweit durch diesen Versuchsaufbau die Qualität der erhobenen Eyetracking-Daten beeinflusst wird. Im nächsten Schritt wurde zur Berechnung dreidimensionaler Blickorte das Anforderungsprofil an einen universellen Algorithmus erstellt und mit einem vektorbasierten Ansatz umgesetzt. Die Besonderheit hierbei besteht in der Berechnung der Blickvektoren anhand der Augen- bzw. Foveaposition und binokularen Eyetracking-Daten. Wie genau dreidimensionale Blickorte anhand dieses Algorithmus berechnet werden können, wurde nachfolgend in realer (Studie II) als auch stereoskopisch projizierter VR-Umgebung (Studie III) untersucht. Anschließend erfolgte die Bestimmung dreidimensionaler Blickbewegungen aus den berechneten 3D-Blickorten. Dazu wurde ein ellipsoider Fixationserkennungsalgorithmus konzipiert und implementiert. Für die dispersionsbasierte Blickbewegungserkennung waren sowohl ein zeitlicher als auch örtlicher Parameter für die Identifikation einer Fixation erforderlich. Da es noch keinerlei Erkenntnisse im dreidimensionalen Bereich gab, wurden die in Studie II und III ermittelten 3D-Blickorte der ellipsoiden Fixationserkennung übergeben und die daraus berechneten Fixationsparameter analysiert. Die entwickelte Methode der räumlichen Blickbewegungsmessung eröffnet die Möglichkeit, bislang in zwei Dimensionen untersuchte Blickmuster nunmehr räumlich zu bestimmen und grundlegende Zusammenhänge zwischen Blickbewegungen und kognitiven Prozessen dreidimensional sowohl in einer realen als auch virtuellen Umgebung zu analysieren.
202

Entwicklung und Erprobung von Instrumenten zur Erfassung von Fachinteresse und Kreativität für Studierende der E-Technik

Burkhardt, Birgit, Hagemeister, Carmen, Lüken, Malte, Ploppa, Antonia 28 May 2018 (has links)
Es wird über die Entwicklung und Erprobung von Instrumenten zur Messung von Ingenieurskreativität und Fachinteresse am Studium der Elektrotechnik berichtet. Im Fall des Fachinteresses wird ein Algorithmus vorgeschlagen um effizient Skalen maßzuschneidern. Für spezifische Kreativität werden die Schwierigkeiten der Erfassung diskutiert und erste Möglichkeit der Lösung dieser Probleme diskutiert. / The development and testing of two scales measuring creativity in engineering and vocational interest is reported. Concerning the scale of vocational interest an algorithm for the efficient tailoring of such scales is proposed. In case of specific creativity the difficulties of the measurement are discussed and first solutions developed.
203

OSA- wie „ohne sichere Aussagekraft“?: Ein systematisches Review zur prädiktiven Aussagekraft von Online-Self-Assessment für den Studienerfolg

Burkhardt, Birgit, Hagemeister, Carmen 28 May 2018 (has links)
Online-Self-Assessments werden zunehmend als Instrumente der niederschwelligen Studienberatung eingesetzt. Mittels einer fachbezogenen Testbearbeitung durch angehende Studierende im Internet mit anschließender Rückmeldung der Testergebnisse, sollen selbstregulierte Studienselektionsprozesse angestoßen und Studienabbruch vermieden werden. Zur qualitativen Überprüfung bestehender Online-Self-Assessments, wurde eine systematische Literaturrecherche im deutschsprachigen Raum durchgeführt, um Angaben über die Aussagekraft für den Studienerfolg machen zu können. Hierbei wurden 19 valide Untersuchen aus 5 Hochschulen, die bis Dezember 2016 erschienen, identifiziert und ausgewertet. Im Leistungsbereich erwiesen sich das schlussfolgernde Denken, als Facette der allgemeinen Intelligenz, und die mathematische Fachkompetenz, als Kombination von Intelligenz und Vorwissen, als gute Indikatoren bei der Vorhersage von Studienerfolg. Im Persönlichkeitsbereich ist die Messung von Leistungsmotivation, Selbstwirksamkeit, Stressbewältigung, Fachinteresse und realistischen Erwartungen an das Studium gewinnversprechend. Eine deutliche Steigerung der prädiktiven Aussagekraft kann durch die Kombination beider Messbereiche zu einem Gesamt-Assessment erfolgen. Abschließend werden die Limitationen diskutiert und ein Forschungsausblick gegeben.
204

„Testung inklusive Training?“: Ein Online-Self-Assessment für Selbstmanagement in der Studieneingangsphase

Burkhardt, Birgit, Hagemeister, Carmen 28 May 2018 (has links)
In diesem Artikel wird die Bedeutung von Selbstmanagement als Schlüsselkompetenz in der Studieneingangsphase diskutiert. Basierend auf dem Modell von Kehr (2005) wird die Entwicklung eines internetbasierten Instrumentes zur Messung von Selbstmanagement (Dresdner SM) vorgestellt. Die Eignung dieses Testes wurde in einer Onlinetestung mit Studierenden der TU Dresden (N=195) überprüft. Es zeigen sich mittlere Zusammenhänge mit Studienerfolgskriterien. Ebenso wird der Zusammenhang zwischen Testung und Training im Fall von Selbstmanagement beleuchtet. Die Limitationen der Studie werden besprochen. / In this paper the key importance of self-management in first-year college achievement is examined. Based on the model of Kehr (2005) this study reports the development of an internet-based instrument measuring self-management in students (Dresdner SM). Students from diverse study fields at the TU Dresden (N=195) responded to that scale in an online assessment. Self-management was found to be a proper predictor for academic performance. Likewise the connection between testing and training in the case of self-management is elucidated. Limitations are discussed.
205

Von den Flussgrößen zum Bestand: Lassen sich einfache dynamische Systeme intuitiv verständlich darstellen?

Brockhaus, Friederike 22 January 2019 (has links)
Die vorliegende Dissertation handelt von einfachen dynamischen Systemen zu Bestands- und Flussgrößen (BF-Systeme). Diese bestehen aus zwei relevanten Größen: aus dem Bestand und den Flussgrößen, bei denen es sich um Zu- und Abfluss handelt. Ein Beispiel hierfür ist ein Wasserbecken, in das Wasser fließt (Zufluss) und aus dem Wasser herausfließt (Abfluss). Der Wasserstand (Bestand) verändert sich über die Zeit hinweg in Abhängigkeit der beiden Flussgrößen. BF-Systeme sind in unserem Leben omnipräsent: Zum einen stellen sie Subsysteme komplexer dynamischer Systeme dar, wie die Weltwirtschaft oder das Klima der Erde. Zum anderen sind wir mit BF-Systemen für sich genommen in unserem Alltag konfrontiert, beispielsweise mit unserem Bankkonto. In vielen Studien erhielten Versuchspersonen die Flussgrößen für einen bestimmten Zeitraum als Liniendiagramm dargeboten. Ihre Aufgabe war es, zu beurteilen, wie sich der Bestand über die Zeit hinweg veränderte, was den meisten große Probleme bereitete. Es ist nicht ungewöhnlich, dass es Versuchspersonen schwer fällt beim Urteilen oder Problemlösen zu adäquaten Lösungen zu kommen. Jedoch zeigte sich oft, dass eine Änderung des Darstellungsformats die Leistung der Versuchspersonen stark verbessert. Beispielsweise ist das der Fall im Bereich der Verarbeitung von Wahrscheinlichkeiten oder beim logischen Schließen. Grundlegend können durch günstige Modifikationen valide Intuitionen angesprochen werden, was zu besserer Leistung in den Urteilen oder beim Problemlösen führt. Ein entsprechender Ansatz wurde im Rahmen der vorliegenden Arbeit für die BF-Systeme gewählt: In vier Studien sollten über Modifikationen der Aufgaben-Darstellung adäquate Intuitionen gefördert werden, die das BF-Verständnis steigern. In den vier Studien dieser Arbeit lag der Schwerpunkt auf der Darstellung der Flussgrößen in einem Diagramm, da dies ein zentraler Bestandteil der Aufgabenbeschreibung von BF-Systemen darstellt. Die erste Studie untersuchte, inwiefern Änderungen unterschiedlicher Beschreibungsdimensionen der BF-Aufgaben die BF-Leistung beeinflussten. Eine zusätzliche gegebene Abbildung des BF-Systems (beispielsweise die schematische Abbildung eines Wasserbeckens) führte zu besserer Leistung: Die Anteile der korrekten Lösungen nahmen zu. Eine Kombination aus Text und Flussdiagramm verschlechterte die Leistung im Gegensatz zu einer Bedingung nur mit Text. Zwei verschiedene Darstellungsformate der BF-Größe (beispielsweise Wasser in einem Wasserbecken) wurden ebenfalls untersucht, wobei sich diesbezüglich kein Unterschied in der BF-Leistung ergab. Zudem wurden die Fehler genauer betrachtet; auch in der vorliegenden Studie nahmen viele Personen an, dass der Verlauf des Bestandes dem Verlauf einer Flussgröße entspricht. Es handelt sich dabei um die sogenannte Korrelations-Heuristik. Basierend auf diesen Ergebnissen erfolgten weitere Modifikationen in der zweiten Studie. Zum einen wurden Zu- und Abfluss getrennt im Koordinatensystem des Flussdiagramms abgetragen. In einer anderen Änderung der Aufgabenbeschreibung erhielten die Versuchspersonen den Nettofluss als zusätzliche Größe. Diese Modifikationen verringerten jedoch das BF-Verständnis. Somit untersuchte die dritte Studie eine etwas stärkere Abwandlung des Flussdiagramms: Die Flussgrößen sahen aus wie Bestandsgrößen für einzelne Zeitpunkte. Um das umzusetzen, wurden die Flussgrößen über Piktogramme dargestellt. In diesen sogenannten symbolischen Bedingungen ergab sich eine starke Verbesserung der BF-Leistung. Jedoch fand keinerlei Transfer-Leistung statt, wenn die Versuchspersonen in einem zweiten Durchgang BF-Aufgaben in klassischem Darstellungsformat, in Form von Liniendiagrammen, bearbeiteten. Die Verbesserung der Leistung resultierte vermutlich aus dem Format in den symbolischen Bedingungen. Weiterhin gingen die Versuchspersonen in diesen Bedingungen schrittweise vor, was ebenfalls das korrekte Lösen der BF-Aufgaben zu unterstützen schien. Die vierte Studie untersuchte, ob eine ähnlich gute Verbesserung in der BF-Leistung auch auftrat, wenn kein schrittweises Vorgehen notwendig war, um zur Lösung zu gelangen. Das symbolische Darstellungsformat wurde außerdem weiterentwickelt, indem Zufluss und Abfluss auf Piktogrammebene unterschiedlich gestaltet waren: Sie wurden über sogenannte ikonische Zeichen dargestellt. Weiterhin wurde die Differenz von Zu- und Abfluss betont, so dass gleich ersichtlich war, welche Flussgröße um wie viele Einheiten überwog. Tatsächlich schnitten die Versuchspersonen der symbolischen Bedingungen besser ab als die in der Baseline-Bedingung mit Liniendiagrammen. Jedoch war der Unterschied in der Leistung nicht mehr so groß wie in der vorangegangenen Studie. Zudem unterschied sich die Leistung zwischen den verschiedenen symbolischen Bedingungen kaum. Eine abschließende Diskussion fasst die Ergebnisse der einzelnen Studien zusammen: Es erfolgt ein Überblick über den Einfluss der Modifikationen in der Darstellung von BF-Systemen. Außerdem werden weitere Ergebnisse zu Personenmerkmalen und die Fehleranalysen thematisiert. Abschließend folgen Überlegungen zum Umgang mit BF-Systemen. / Dynamic systems, also known as stock and flow systems (SF systems), consist of a stock and two kinds of flows. For example, a tub of water contains the stock, a given amount of water in this case. The inflow consists of water flowing in, and the outflow of water flowing out. Varied experiments have tested how well such systems are understood. Usually, participants were given the patterns of in- and outflow over time and had to judge how the stock changes, given these flows. This led to a sometimes surprisingly high amount of wrong solutions. Correct understanding of these systems is very important, however. We often face them in everyday life and in our society. The amount of CO2 in the atmosphere and how it is changing over time is an example of a SF system. The main objective of the present work was to test interventions for increasing the rates of correct solutions in SF tasks. I assumed that the way flows are represented has an impact on the spontaneous understanding of SF systems. Up to now, flows have most often been represented as line graphs. In the present work, the focus lay on analysing different modifications of the flow graphs that should lead to intuitive understanding of the systems. In four studies, where most modifications did not support SF understanding, using iconic signs supported participants in finding the correct solutions. Furthermore, I analysed the incorrect solutions and some moderator variables such as gender and mathematical ability. The results showed that these moderator variables influenced performance: males performed better, and higher mathematical skills supported better SF understanding. One systematic error, the correlation heuristic, occurred in all cases. In the future, more studies about representing flows with iconic signs should be done, as the present results suggest that iconic signs might support SF understanding.
206

Empirical Studies on Early Childhood Education in Germany

Coneus, Katja 05 February 2010 (has links)
This dissertation considers different aspects of early childhood education in Germany. It aims at providing an empirical contribution to four issues in early childhood education: the development of cognitive and noncognitive skills (chapter 1-3), institutional child care (chapter 4), the intergenerational transmission of a child's health (chapter 5), and the long-term consequences of early noncognitive skills (chapter 6). This is done by using two data sets: First, we use the mother and child data from the German Socio-economic Panel (SOEP) for the years 2003-2008. The mother and child questionnaire, firstly implemented in 2003, contains detailed information on a child's cognitive and noncognitive skills and health, starting from the time of birth. This information on a child's human capital was assessed by the mothers. Second, we exploit a prospective psychological longitudinal panel study on child development from birth until adulthood, the Mannheim Study of Children at Risk (MARS). These data allow us to use more reliable information on a child's cognitive and noncognitive skills from the age of three months on. However, this study is not representative because children at risk are oversampled. Altogether, the different studies suggest that parental investment (economic resources or non-economic resources) in children explain, at least to some extent, the development of cognitive and noncognitive skills as well as the child's health status. Scope for further research is pointed out, particularly related to long-term consequences of cognitive and noncognitive skills acquired during early childhood. A deeper understanding of how skills develop over the life cycle promises to enrich the economic theory and helps to understand the sources as well as the solutions for inequality. / Die vorliegende Dissertation untersucht verschiedene Aspekte der frühkindlichen Bildung in Deutschland. Während sich die empirische Bildungsforschung in den letzten Jahren intensiv mit Fragen der institutionellen Bildung beschäftigt hat, weisen aktuell geführte familien- und bildungspolitische Diskussionen und neuere Forschungsstudien zunehmend auf die Bedeutung der frühkindlichen Entwicklungsphase als erste Phase für die Entwicklung und Förderung von Humankapital hin. Die Arbeit nimmt die aktuelle Diskussion zum Anlass, unterschiedliche Aspekte der frühkindlichen Bildung in Deutschland zu untersuchen. Die ersten drei Kapitel dieser Arbeit untersuchen, wie sich Fähigkeiten in der (frühen) Kindheit entwickeln. Dafür wird eine Fähigkeitsproduktionsfunktion zugrunde gelegt und deren zentrale Eigenschaften zu unterschiedlichen Phasen innerhalb der (frühen) Kindheit auf ihre empirische Relevanz hin untersucht. Darüber hinaus ist es möglich, Wirkungen unterschiedlicher Investitionen für die Entwicklung kognitiver und nicht-kognitiver Fähigkeiten innerhalb der ersten Lebensjahre zu beleuchten und geeignete politische Instrumente daraus abzuleiten. Kapitel vier beleuchtet den Aspekt der institutionellen Kinderbetreuung für die frühkindliche Bildung in Westdeutschland. Die zugrundeliegende Überlegung dieses Abschnitts ist die Frage, ob der institutionellen Kinderbetreuung in Deutschland neben seiner Betreuungsfunktion neuerdings auch eine Bildungsfunktion zugesprochen wird. Zahlreiche Studien zeigen, dass die Gesundheit in der frühen Kindheit eine zentrale Rolle für die Gesundheit im Erwachsenenalter spielt, und gleichzeitig den Erwerb von Fähigkeiten in der frühen Kindheit und damit auch für spätere Lebensphasen unmittelbar beeinflusst. Die Rolle der Gesundheit innerhalb in der ersten Lebensjahre wird in Kapitel 5 untersucht. Neben der unumstrittenen Bedeutung kognitiver Fähigkeiten für eine Vielzahl ökonomischer und nicht-ökonomischer Outcomes, zeigen neuere Studien die Bedeutung nicht-kognitiver Fähigkeiten. Im letzten Kapitel (sechs) werden daher mittel- bis langfristige Konsequenzen geringer nicht-kognitiver Fähigkeiten in der frühen Kindheit für eine Reihe von sozialen Outcomes (Schulleistungen, Gesundheitsverhalten, Persönlichkeit) im Jugendalter analysiert.
207

Understanding age-related prospective memory performance: The role of cognitive, motivational and emotional mechanisms associated with age differences in the delayed execution of intended actions

Schnitzspahn, Katharina 17 August 2011 (has links)
A pervasive real-world memory task is remembering to carry out intended activities at appropriate moments in the future, such as remembering to call one’s mother after returning from work or to hand a message to a colleague when seeing him in the office on the next morning. Such types of tasks are termed prospective memory (PM) tasks (Einstein & McDaniel, 1996). PM has been identified as one of the most frequent everyday memory challenges (e.g., Maylor, 1990), particularly in old age (McDaniel, Einstein, & Rendell, 2008) and an intact PM is considered to be crucial for the maintenance of independent living (Kliegel & Martin, 2003). Therefore, many researchers have focused on the exploration of possible age differences in PM. While age-related deficits were found in standard lab-based PM tasks, age-related benefits occured in naturalistic tasks that are carried out in participants’ everyday lives. This surprising pattern has been called the age-PM-paradox (Rendell & Craik, 2000). It has been supported by a meta-analysis comparing PM age effects found in studies that focused either on lab-based or on naturalistic PM tasks (Henry, MacLeod, Phillips, & Crawford, 2004). However, the mechanisms which are critical in determining the direction of age effects remain poorly delineated. Thus, the overall aim of the research programme presented in the present thesis was to investigate the age-PM-paradox as well as potential cognitive, motivational and emotional mechanisms and processes associated with age-related PM performance. For that purpose, three experimental studies were conducted testing adult age effects in different PM task settings with different task material. Furthermore, several possible underlying mechanisms suggested by the literature on age effects in PM were measured and/ or varied experimentally. The first aim of Study 1 was to cross-validate the age-PM-paradox within a single sample. The second aim was to empirically explore the relative importance of four recently proposed factors (motivation, metacognitive awareness, activity absorption, and control over the task) that may be associated with the direction of age effects inside and outside of the laboratory. For that purpose, 20 young and 20 older adults performed a lab-based and a naturalistic PM task, which were similar in structure and demand. The level of control was experimentally manipulated in both task settings. The remaining possibly influencing factors (motivation, metacognitive awareness, and activity absorption) were assessed via questionnaires in the laboratory and with a daily diary in the field. First, analysing mean level age differences, the paradox was confirmed. Second, exploring possible correlates of the paradox revealed that the level of daily activity absorption (i.e., everyday stress) was the most important mechanism in naturalistic PM performance. Further, high motivation and good metacognitive awareness were associated with age benefits in PM performance in the naturalistic task, while high ongoing activity absorption and low control over the PM cue were related to deficits in lab-based tasks. Thus, Study 1 confirmed the age-PM-paradox within one sample and with carefully matched lab-based and naturalistic tasks. In addition, the results indicate that the relative importance of the suggested factors may vary as a function of setting. While cognitive factors were most influential in the laboratory, motivational and knowledge-based factors were associated with high PM performance in the naturalistic task. The strong association between PM performance in the field and everyday stress highlights the need for future studies exploring the mechanisms underlying this effect. Results from Study 1 suggest that cognitive resources are most influential for PM age effects in the laboratory. Yet, it is not clear, which specific cognitive resources are needed for successful PM performance and if these processes differ between young and older adults. Thus, Study 2 explored the role of executive functions (i.e. shifting, updating and inhibition) as possible developmental mechanisms associated with PM age effects. 170 young and 110 older adults performed a battery of cognitive tests including measures of PM, shifting, updating, inhibition, working memory and speed. A comprehensive set of statistical approaches (e.g. median analyses, structural equation modelling) was used to analyze the possible cognitive correlates in predicting PM performance. First, age effects were confirmed in PM and also obtained in measures of executive control. Moreover, the facets of executive control differently predicted PM performance. Specifically, shifting was the strongest predictor of PM performance in young and older adults as well as for explaining age differences in PM. Thus, Study 2 clarified the role of different facets of controlled attention in age effects in PM and bears important conceptual implications: The results suggest that executive functions are important developmental mechanisms of PM across adulthood beyond working memory and speed. Specifically, shifting appeared to be an essential aspect of cognitive control involved in age-related PM performance. Moreover, examining PM as a latent construct confirmed the convergent and discriminant validity of PM. This demonstrates PM as a separate cognitive construct and suggests that PM is related to, but not identical with, executive control. Study 3 was set out to explore if the amount of cognitive resources needed to successfully perform a PM task in the laboratory can be influenced by the emotionality of the task material. First studies suggested that emotional task material may enhance PM performance in young and older adults by heightening the salience of the task and thereby reducing the need for controlled attention. However, the extent and mechanisms of this effect are still under debate. Therefore, Study 3 explored possible differential effects of PM target cue valence on PM age effects. For that purpose, 45 young and 41 older adults performed a PM task in which emotional valence of the PM cue was manipulated (positive, negative, neutral). Results revealed an interaction indicating that age differences were smaller in both emotional valence conditions compared to the neutral condition. This finding supports an emotionally enhanced memory effect in PM, but only for the older adults as PM performance in young adults was not affected by cue valence. From a conceptual perspective, the results from Study 3 may also contribute to the explanation of the age-PM-paradox, as they suggest that the neutral material usually applied in lab-based studies might overestimate PM age effects. In summary, the present thesis makes an important contribution to the ongoing conceptual debate concerning adult age effects in PM performance assessed in the laboratory versus participants’ everyday lives. Results strongly suggest that mostly different variables may be crucial for understanding PM age deficits in the laboratory and age benefits in naturalistic PM tasks. Successful PM performance in the laboratory seems to require high levels of cognitive resources. The present results suggest that shifting ability is especially relevant in this respect. On a task level the emotionality of the material seems to influence the required amount of cognitive resources as it reduced PM age effects. Everyday stress seems to be particularly important for successful PM performance in the field. Thus, possible future studies should specify the relation between stress and PM as outlined in the general discussion.
208

Disentangling neuronal pre- and post-response activation in the acquisition of goal-directed behavior through the means of co-registered EEG-fMRI

Baum, Fabian 27 January 2021 (has links)
Behavior is considered goal-directed when the actor integrates information about the subsequent outcome of an action (Balleine & O'Doherty, 2010; Dickinson & Balleine, 1994; Kiesel & Koch, 2012), potentially enabling the anticipation of consequences of an action. Thus, it requires prior acquisition of knowledge about the current contingencies between behavioral responses and their outcomes under certain stimulus conditions (J. Hoffmann & Engelkamp, 2013). This association chain enables events lying in the future to be mentally represented and assessed in terms of value and achievability. However, while neural correlates of instructed goal-directed action integration processes have already been examined in a functional magnetic resonance imaging (fMRI) study using this paradigm (Ruge & Wolfensteller, 2015), there has been no information if those processes are also reflected in Electroencephalography (EEG) and if so which specific EEG parameters are modulated by them. This dissertation set out to investigate neurocognitive mechanisms of instructed outcome response learning utilizing two different imaging methods, namely EEG and fMRI. Study 1 was an exploratory study to answer the question what kinds of learning-related EEG correlates were to expect. The O-R outcome integration specific EEG correlates identified in Study 1 served as regressors in a unified general linear model (EEG-informed fMRI analysis) in the co-registered EEG-fMRI study (Study 2). One of the key questions in this study was if the EEG signal could help to differentiate between BOLD pre-response activation associated with processes related to response preparation or initiation and activation associated with post-response outcome integration processes. The foundation to both studies of this work was an experimental paradigm of instructed S-R-O learning, which included a learning and a test phase. Stimuli were four abstract visual patterns that differed in each block. Each visual stimulus required a distinct manual response and was predictably followed by a distinct auditory outcome. Instructions were delivered via a “guided implementation” procedure in which the instruction was embedded within the first three successful behavioral implementation trials. In these first three trials, the visual stimulus was followed by an imperative stimulus highlighting the correct response. The guided implementation phase was followed by an unguided implementation phase where the correct response now had to be retrieved from memory. Behaviorally, the strength of acquired O-R associations can be analyzed via O-R compatibility effects measured in a subsequent outcome-priming test phase (Greenwald, 1970). In this test phase a previously learned outcome becomes an imperative stimulus that requires either the response, which produced that outcome in the preceding learning phase (O-R compatible), or a response, which produced a different outcome (O-R incompatible). The experimental design was embedded into an EEG recording setup in study 1 while study 2 comprised a simultaneous EEG-fMRI recording setup in which EEG scalp potentials were continuously recorded during the experimental session inside the MR scanner bore. Study 1 revealed various ERP markers correlated with outcome response learning. An ERP post-response anterior negativity following auditory outcomes was increasingly attenuated as a function of the acquired association strength. This suggests that previously reported action-induced sensory attenuation effects under extensively trained free choice conditions can be established within few repetitions of specific R-O pairings under forced choice conditions. Furthermore, an even more rapid development of a post-response but pre-outcome fronto-central positivity, which was reduced for high R-O learners, might indicate the rapid deployment of preparatory attention towards predictable outcomes. Finally, the study identified a learning-related stimulus-locked activity modulation within the visual P1-N1 latency range, which was thought to reflect the multi-sensory integration of the perceived antecedent visual stimulus with the anticipated auditory outcome. In general, study 2 was only partially able to replicate the EEG activity dynamics related to the formation of bidirectional R-O associations that were observed in study 1. Primarily, it was able to confirm the modulation in EEG negativity in the visual P1-N1 latency range over the learning course. The EEG-informed analysis revealed that learning-related modulations of the P1-N1 complex are functionally coupled to activation in the orbitofrontal cortex (OFC). More specifically, growing attenuation of the EEG negativity increase from early to late SRO repetition levels in high R-O learners was associated with an increase in activation in the OFC. An additional exploratory EEG analysis identified a recurring post outcome effect at central electrode sites expressed in a stronger negativity in late compared to early learning stages. This effect was present in both studies and showed no correlation with any of the behavioral markers of learning. The EEG-informed fMRI analysis resulted in a pattern of distinct functional couplings of this parameter with different brain regions, each correlated with different behavioral markers of S-R-O learning. First of all, increased coupling between the late EEG negativity and activation in the supplementary motor area (SMA) was positively correlated with the O-R compatibility effect. Thus, high R-O learners exhibited a stronger coupling than low R-O learners. Secondly, increased couplings between the late EEG negativity and activation in the somatosensory cortex as well as the dorsal caudate, on the other hand, were positively correlated with individual reaction time differences between early and late stages of learning. Regarding activation patterns prior to the behavioral response the results indicate that the OFC could serve as a (multimodal) hub for integrating stimulus information and information about its associated outcome in an early pre-stage of action selection and initiation. Learnt S-O contingencies would facilitate initiating the motor program of the action of choice. Hence, the earlier an outcome is anticipated (based on stimulus outcome associations), the better it will be associated with its response, eventually leading to stronger O-R compatibility effects later on. Thus, one could speculate that increased activation in response to S-R-O mappings possibly embodies a marker for the ongoing transition from mere stimulus-based behavior to a goal-directed behavior throughout the learning course. Post-response brain activation revealed a seemingly two-fold feedback integration stream of O-R contingencies. On one hand the SMA seems to be engaged in bidirectional encoding processes of O-R associations. The results promote the general idea that the SMA is involved in the acquisition of goal-directed behavior (Elsner et al., 2002; Melcher, Weidema, Eenshuistra, Hommel, & Gruber, 2008; Melcher et al., 2013). Together with prior research (Frimmel, Wolfensteller, Mohr, & Ruge, 2016) this notion can be generalized not only to extensive learning phases but also to learning tasks in which goal-directed behavior is acquired in only few practice trials. However, there is an ongoing debate on whether SMA activation can be clearly linked to sub-processes prior or subsequent to an agent’s action (Nachev, Kennard, & Husain, 2008). The results of this work provide additional evidence favoring an involvement of the SMA only following a performed action in response to an imperative stimulus and even more, subsequent to the perception of its ensuing effect. This may give rise to the interpretation that the SMA is associated with linking the motor program of the performed action to the sensory program of the perceived effect, hence establishing and strengthening O-R contingencies. Furthermore, the analysis identified an increased coupling of a late negativity in the EEG signal and activation in the dorsal parts of the caudate as well as the somatosensory cortex. The dorsal caudate has not particularly been brought into connection with O-R learning so far. I speculate that the coupling effect in this part of the caudate reflects an ongoing process of an early automatization of the acquired behavior. It has already be shown in a similar paradigm that behavior can be automatized within only few repetitions of novel instructed S-R mappings (Mohr et al., 2016).:Table of contents Table of contents II List of Figures IV List of Tables VI List of Abbreviations VII 1 Summary 1 1.1 Introduction 1 1.2 Study Objectives 2 1.3 Methods 3 1.4 Results 4 1.5 Discussion 4 2 Theoretical Background 7 2.1 Introduction 7 2.2 Theories of acquiring goal-directed behavior 9 2.2.1 Instrumental learning 9 2.2.1.1 Behavioral aspects 9 2.2.1.2 Neurophysiological correlates 14 2.2.2 Acquisition of goal-directed behavior according to ideomotor theory 16 2.2.2.1 Behavioral aspects 16 2.2.2.2 Neurophysiological correlates 22 2.3 Summary 25 2.4 Methodological background 26 2.4.1 Electroencephalography (EEG) 26 2.4.2 Functional magnetic resonance imaging (fMRI) 28 2.4.3 Co-registered EEG-fMRI 29 3 General objectives and research questions 34 4 Study 1 – Learning-related brain-electrical activity dynamics associated with the subsequent impact of learnt action-outcome associations 36 4.1 Introduction 36 4.2 Methods 39 4.3 Results 47 4.4 Discussion 60 5 Study 2 - Within trial distinction of O-R learning-related BOLD activity with the means of co-registered EEG information 64 5.1 Introduction 64 5.2 Methods 66 5.3 Results 86 5.4 Discussion 101 6 Concluding general discussion 109 6.1 Brief assessment of study objectives 109 6.2 Novel insights into rapid instruction based S-R-O learning? 109 6.2.1 Early stimulus outcome information retrieval indicates the transition from stimulus based behavior to goal-directed action 110 6.2.2 Post-response encoding and consolidation of O-R contingencies enables goal-directedness of behavior 112 6.3 Critical reflection of the methodology and outlook 116 6.3.1 Strengths and limitations of this work 116 6.3.2 Data quality assessment 117 6.3.3 A common neural foundation for EEG and fMRI? 119 6.3.4 How can co-registered EEG-fMRI contribute to a better understanding of the human brain? 121 6.4 General Conclusion 123 7 References 124 Danksagung Erklärung
209

Situation-appropriate Investment of Cognitive Resources

Ott, Florian 29 March 2022 (has links)
The human brain is equipped with the ability to plan ahead, i.e. to mentally simulate the expected consequences of candidate actions to select the one with the most desirable expected long-term outcome. Insufficient planning can lead to maladaptive behaviour and may even be a contributory cause of important societal problems such as the depletion of natural resources or man-made climate change. Understanding the cognitive and neural mechanisms of forward planning and its regulation are therefore of great importance and could ultimately give us clues on how to better align our behaviour with long-term goals. Apart from its potential beneficial effects, planning is time-consuming and therefore associated with opportunity costs. It is assumed that the brain regulates the investment into planning based on a cost-benefit analysis, so that planning only takes place when the perceived benefits outweigh the costs. But how can the brain know in advance how beneficial or costly planning will be? One potential solution is that people learn from experience how valuable planning would be in a given situation. It is however largely unknown how the brain implements such learning, especially in environments with large state spaces. This dissertation tested the hypothesis that humans construct and use so-called control contexts to efficiently adjust the degree of planning to the demands of the current situation. Control contexts can be seen as abstract state representations, that conveniently cluster together situations with a similar demand for planning. Inferring context thus allows to prospectively adjust the control system to the learned demands of the global context. To test the control context hypothesis, two complex sequential decision making tasks were developed. Each of the two tasks had to fulfil two important criteria. First, the tasks should generate both situations in which planning had the potential to improve performance, as well as situations in which a simple strategy was sufficient. Second, the tasks had to feature rich state spaces requiring participants to compress their state representation for efficient regulation of planning. Participants’ planning was modelled using a parametrized dynamic programming solution to a Markov Decision Process, with parameters estimated via hierarchical Bayesian inference. The first study used a 15-step task in which participants had to make a series of decisions to achieve one or multiple goals. In this task, the computational costs of accurate forward planning increased exponentially with the length of the planning horizon. We therefore hypothesized that participants identify ‘distance from goal’ as the relevant contextual feature to guide their regulation of forward planning. As expected we found that participants predominantly relied on a simple heuristic when still far from the goal but progressively switched towards forward planning when the goal approached. In the second study participants had to sustainably invest a limited but replenishable energy resource, that was needed to accept offers, in order to accumulate a maximum number of points in the long run. The demand for planning varied across the different situations of the task, but due to the large number of possible situations (n = 448) it would be difficult for the participants to develop an expectation for each individual situation of how beneficial planning would be. We therefore hypothesized, that to regulate their forward planning participants used a compressed tasks representation, clustering together states with similar demands for planning. Consistent with this, reaction times (operationalising planning duration) increased with trial-by-trial value-conflict (operationalising approximate planning demand), but this increase was more pronounced in a context with generally high demand for planning. We further found that fMRI activity in the dorsal anterior cingulate cortex (dACC) increased with conflict, but this increase was more pronounced in a context with generally high demand for planning as well. Taken together, the results suggest that the dACC integrates representations of planning demand on different levels of abstraction to regulate prospective information sampling in an efficient and situation-appropriate way. This dissertation provides novel insights into the question how humans adapt their planning to the demands of the current situation. The results are consistent with the view that the regulation of planning is based on an integrated signal of the expected costs and benefits of planning. Furthermore, the results of this dissertation provide evidence that the regulation of planning in environments with real-world complexity critically relies on the brain’s powerful ability to construct and use abstract hierarchical representations.
210

Measuring Cognitive Load – Opportunities and Challenges

Krieglstein, Felix 28 July 2023 (has links)
Die Cognitive Load Theory (CLT) postuliert, dass das Lernen neuer, komplexer Informationen mit einer Belastung des Arbeitsgedächtnisses des Lernenden einhergeht. Nachdem die Theorie erstmals 1988 von John Sweller postuliert wurde, arbeitete eine kleine Gruppe von Forschern an Universitäten in Australien und den Niederlanden an ihrer Weiterentwicklung. Sie entwickelte sich schnell zu einer der populärsten Theorien in der pädagogischen Psychologie und im Instruktionsdesign. Die CLT basiert auf Erkenntnissen der Kognitionspsychologie und geht davon aus, dass das Arbeitsgedächtnis nur eine begrenzte Anzahl von Informationselementen simultan verarbeiten kann, wodurch die Fähigkeit, neue Informationen zu verarbeiten, stark eingeschränkt ist. Auf der Grundlage der CLT wurden eine Reihe von Empfehlungen und Prinzipien abgeleitet, die den Lernenden helfen sollen, ihre verfügbaren kognitiven Ressourcen optimal für das Lernen zu nutzen, um Informationen in Form von Schemata in das Langzeitgedächtnis zu übertragen. Ziel ist es, eine Überlastung des Arbeitsgedächtnisses (d.h. eine kognitive Überlastung) zu vermeiden, da diese das Lernen behindern. Nach der Theorie sind drei Arten von kognitiver Belastung während des Lernens relevant. Während der Intrinsic Cognitive Load (ICL) die Komplexität der zu lernenden Informationen unter Berücksichtigung des Vorwissens des Lernenden beschreibt, wird der Extraneous Cognitive Load (ECL) durch die Gestaltung des Lernmaterials bestimmt, welcher sich negativ auf den Lernerfolg auswirken kann. Während ICL und ECL konzeptionell klar definiert sind, wird die Definition der dritten Belastungsart, des Germane Cognitive Load (GCL), innerhalb der CLT kontrovers diskutiert. In diesem Zusammenhang ist unklar, ob der GCL eine eigenständige Quelle kognitiver Belastung darstellt oder ob er sich lediglich auf die kognitiven Ressourcen bezieht, die der Lernende mental aufwendet, um Schemata aufzubauen. Daraus hat sich in den letzten Jahren eine Debatte darüber entwickelt, ob der GCL überhaupt ein Teil der CLT ist und ob es ausreicht, die kognitive Belastung während des Lernens mit dem ICL und dem ECL zu beschreiben. Auch die Annahme, dass die drei Arten unabhängig voneinander additiv zur Gesamtbelastung beitragen, wurde häufig in Frage gestellt. Neben den offenen theoretischen Fragen innerhalb der CLT stellt die Messung der verschiedenen Belastungsarten die größte Herausforderung für die Forschung dar. Latente Konstrukte wie die kognitive Belastung können nur indirekt gemessen werden, wodurch es umso wichtiger ist, die Reliabilität und Validität entsprechender Messungen zu überprüfen. Von besonderer Bedeutung ist dabei die multidimensionale Messung (d.h. die separate Messung der einzelnen Arten der kognitiven Belastung) sowie der optimale Zeitpunkt der Messung (d.h. während oder nach dem Lernen). Ziel dieser Dissertation ist es daher, die Chancen und Herausforderungen der Messung kognitiver Belastung zu diskutieren. Da die kognitive Belastung in der Praxis häufig mit Fragebögen gemessen wird, wird diese Erhebungsmethode in der vorliegenden Dissertation vorrangig betrachtet. So wurde in einer Metaanalyse überprüft, inwieweit die zu diesem Zeitpunkt verfügbaren Fragebögen in der Lage sind, die verschiedenen Arten kognitiver Belastung reliabel und valide zu messen. Dazu wurden experimentelle Studien aus dem Bereich des multimedialen Lernens herangezogen, in denen die CLT eine ganz wesentliche Rolle spielt. Darüber hinaus wurde aufgrund konzeptueller und psychometrischer Inkonsistenzen der verfügbaren Fragebögen ein neuer Fragebogen entwickelt und validiert, der vor allem den Lernenden helfen soll, besser zwischen den verschiedenen Arten der kognitiven Belastung zu unterscheiden. In einer experimentellen Studie wurde zudem untersucht, wie sich unterschiedliche Komplexitätsgrade innerhalb eines Lernmaterials auf die Gesamtbewertung der kognitiven Belastung durch den Lernenden auswirken. Damit verbunden war die Frage, ob sich Lernende einen Ankerpunkt (z.B. den ersten Eindruck) suchen, von dem aus sie das gesamte Lernmaterial hinsichtlich der kognitiven Belastung bewerten. Insgesamt zeigte sich, dass das Konstrukt der kognitiven Belastung mit hoher interner Konsistenz gemessen werden kann, wobei sich Einschränkungen hinsichtlich der Validität ergaben. So deuten die Korrelationen zwischen den einzelnen Arten der kognitiven Belastung darauf hin, dass die Lernenden nicht ausreichend zwischen ihnen differenzieren können. Dies gilt auch dann, wenn die Items im Fragebogen so formuliert sind, dass die Lernenden erkennen sollten, welche Art von kognitiver Belastung sie beurteilen sollen. Darüber hinaus spiegeln sich die theoretischen Annahmen der CLT nicht immer in den Messergebnissen wider. Es ist unklar, ob diese Ambivalenz auf theoretische Unzulänglichkeiten oder auf Messungenauigkeiten zurückzuführen ist. Forschende sollten ihre Messergebnisse vor diesem Hintergrund kritisch reflektieren. Da es sich bei der kognitiven Belastung um ein dynamisches Konstrukt handelt, dessen Intensität während des Lernprozesses stark variieren kann, werden die Forschenden dazu angehalten, die Messung zu geeigneten Zeitpunkten während des Lernprozesses durchzuführen. Basierend auf den Erkenntnissen dieser Dissertation werden Handlungsempfehlungen für den zukünftigen Einsatz von Fragebögen zur Messung kognitiver Belastung abgeleitet und theoretische Implikationen diskutiert.:Zusammenfassung 3 Summary 5 1 Introduction 7 2 Foundations of Cognitive Load Theory 9 2.1 Human Cognitive Architecture 9 2.2 Evolutionary Educational Psychology 12 2.3 The Construct of Cognitive Load 14 2.4 Types of Cognitive Load 16 3 Cognitive Load Theory in Multimedia Learning 22 4 Measuring Cognitive Load 25 4.1 Physiological Measures 25 4.2 Dual-task Approaches 26 4.3 Self-rating Scales 27 5 Conceptual and Psychometric Issues in Cognitive Load Research 31 5.1 Three-factor Model and Additivity Hypothesis 31 5.2 Reliable and Valid Measurement of Cognitive Load with Subjective Scales 33 5.3 Timing of Cognitive Load Measurement 36 6 Article 1: A systematic meta-analysis of the reliability and validity of subjective cognitive load questionnaires in experimental multimedia learning research 40 7 Article 2: Development and validation of a theory-based questionnaire to measure different types of cognitive load 98 8 Article 3: The distorting role of primacy effects when reporting cognitive load in a learning material with varying complexities 136 9 Discussion 193 9.1 Contributions of this Thesis 193 9.2 Limitations and Future Directions 196 9.3 Conclusion 197 10 References 198 Danksagung 208 / Cognitive Load Theory (CLT) postulates that learning new, complex information places a burden on the learner’s working memory. After the theory was first postulated by John Sweller in 1988, a small group of researchers at universities in Australia and the Netherlands worked to develop it further. It quickly became one of the most popular theories in educational psychology and instructional design. CLT is based on findings in cognitive psychology and posits that working memory can only process a limited number of information elements simultaneously, severely limiting its ability to process new information. Based on CLT, a set of recommendations and principles has been derived to help learners make optimal use of their available cognitive resources for learning in order to transfer information to long-term memory in the form of schemata. The goal is to avoid overloading working memory (i.e., cognitive overload), which impedes learning. According to the theory, three types of cognitive load are relevant during learning. While intrinsic cognitive load (ICL) describes the complexity of the information to be learned, taking into account the learner's prior knowledge, extraneous cognitive load (ECL) is determined by the design of the learning material and can have a negative impact on learning success. While ICL and ECL are conceptually well-defined, the definition of the third type of load, germane cognitive load (GCL), is controversial within CLT. In this context, it is unclear whether GCL is a source of cognitive load in its own right or whether it simply refers to the cognitive resources that the learner mentally expends to build schemata. This has led to a debate in recent years as to whether GCL is a part of CLT at all, and whether it is sufficient to use the ICL and ECL to describe cognitive load during learning. The assumption that the three types additively and independently contribute to the total cognitive load has also been questioned. In addition to the open theoretical questions within CLT, the measurement of the different types of cognitive load represents the greatest challenge for research. Latent constructs such as cognitive load can only be measured indirectly, making it all the more important to examine the reliability and validity of such measures. Of particular importance is multidimensional measurement (i.e., measuring each type of cognitive load separately) and the optimal timing of measurement (i.e., during or after learning). Thus, the purpose of this thesis is to discuss the opportunities and challenges of measuring cognitive load. Since cognitive load is often measured in practice with questionnaires, this thesis prioritizes this survey method. Therefore, a meta-analysis was conducted in order to examine the extent to which questionnaires available at this time are able to reliably and validly measure the different types of cognitive load. For this purpose, experimental studies from the field of multimedia learning, in which CLT plays a very important role, were used. In addition, due to conceptual and psychometric inconsistencies of available questionnaires, a new questionnaire was developed and validated, mainly to help learners better differentiate between different types of cognitive load. An experimental study was also conducted to test how different levels of complexity within a learning material affect the learner’s overall assessment of cognitive load. Related to this was the question of whether learners seek an anchor point (e.g., first impression) from which they evaluate the entire learning material in terms of cognitive load. Overall, it was found that the construct of cognitive load can be measured with a high degree of internal consistency, although there are limitations in terms of validity. For example, the correlations between the different types of cognitive load indicate that the learners cannot sufficiently differentiate between them. This is true even though the items in the questionnaire are worded in such a way that learners should be able to identify which type of cognitive load they are being asked to assess. Furthermore, the theoretical assumptions of CLT are not always reflected in the measurement results. It is unclear whether this ambivalence is due to theoretical shortcomings or measurement inaccuracies. In light of this, researchers should critically reflect on their measurement results. Because cognitive load is a dynamic construct whose intensity can vary widely during learning, researchers are encouraged to measure it at appropriate times during the learning process. Based on the findings of this thesis, recommendations for the future use of questionnaires to measure cognitive load are derived and theoretical implications are discussed.:Zusammenfassung 3 Summary 5 1 Introduction 7 2 Foundations of Cognitive Load Theory 9 2.1 Human Cognitive Architecture 9 2.2 Evolutionary Educational Psychology 12 2.3 The Construct of Cognitive Load 14 2.4 Types of Cognitive Load 16 3 Cognitive Load Theory in Multimedia Learning 22 4 Measuring Cognitive Load 25 4.1 Physiological Measures 25 4.2 Dual-task Approaches 26 4.3 Self-rating Scales 27 5 Conceptual and Psychometric Issues in Cognitive Load Research 31 5.1 Three-factor Model and Additivity Hypothesis 31 5.2 Reliable and Valid Measurement of Cognitive Load with Subjective Scales 33 5.3 Timing of Cognitive Load Measurement 36 6 Article 1: A systematic meta-analysis of the reliability and validity of subjective cognitive load questionnaires in experimental multimedia learning research 40 7 Article 2: Development and validation of a theory-based questionnaire to measure different types of cognitive load 98 8 Article 3: The distorting role of primacy effects when reporting cognitive load in a learning material with varying complexities 136 9 Discussion 193 9.1 Contributions of this Thesis 193 9.2 Limitations and Future Directions 196 9.3 Conclusion 197 10 References 198 Danksagung 208

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