The article starts with observations about an increasing marginalization of professional journalism in public communication. This development is mainly driven by two factors, decreasing interest in the public sphere and increasing selective exposure. Based on these observations, the author develops a definition of the core societal functions of journalism, that is, validation and shared reality. Assigning to professional journalism the role of the ‘new knowledge profession’ he looks for areas of competence that would need to be taught in academic programs to furnish the profession with the necessary skills and make journalism a ‘de facto profession’. Finally, he discusses constraints on such a strategy in educational philosophies, the trade, and the changing demand of professional news.

The publication-based dissertation investigates how to leverage corporate venturing units for the continuous stra- tegic renewal of established companies. It includes four self-contained research papers, from which three are de- veloped for publication in peer-reviewed academic journals, and one for publication as an academic teaching case study. The first paper uses the methodology of a systematic literature review to integrate different research streams of organizational ambidexterity, dynamic capabilities, and corporate venturing. As a result, it provides an inte- grated framework and identifies interlinked-ambidextrous corporate venturing units as a promising research av- enue for strategic corporate venturing. The second paper applies a multiple-case study approach to differentiate contemporary corporate venturing units from a strategic renewal perspective. As a result, it can provide a novel typology and suggest a first organizational framework for strategic corporate venturing. The third paper investi- gates the identified interlinked-ambidextrous corporate venturing units deeper through additional qualitative data collection and analysis. This results in a proposed organizational model of strategic corporate venturing with spe- cific organizational antecedents alongside process activities, dynamic capabilities and organizational interlinks as possible enablers, and ambidextrous orientation as a possible mediator to develop organizationally consequential new business. The fourth paper helps to apply these findings by describing the strategic renewal challenge of the digital scale-up Freeletics and leading through the organizational set-up of a suitable strategic corporate venturing project in the teaching note. To integrate all papers within one dissertation, they are framed with an introductory and concluding section. The introduction describes the overall need and motivation for the research and intro- duces the key theoretical concepts as well as the four research papers and their publication status. The concluding section provides theoretical and practical implications, as well as limitations and future research opportunities across all included papers. Altogether, the dissertation enhances existing corporate venturing theory to better lev- erage the concept for strategic renewal and provides new insights into the establishing and application of dynamic capabilities and organizational ambidexterity in dedicated corporate venturing units.

Im Rahmen von drei Teilstudien wurde mathematische Schülerleistung aus einer differentialpsychologischen Perspektive untersucht. Die hierfür verwendeten Daten stammten von 29.386 deutschen Neuntklässlern, die am Programme for International Student Assessment (PISA) im Jahr 2000 teilnahmen. In Studie 1 wurden ausgehend von Strukturtheorien kognitiver Fähigkeiten verschiedene Strukturmodelle mathematischer Schülerleistung konfirmatorisch geprüft. So wurde mathematische Schülerleistung in Form eines Nested-Faktormodell als additive Funktion einer mathematikspezifischen Fähigkeit (M´) und der allgemeinen kognitiven Fähigkeit (g) spezifiziert. Dieses Modell wies einen besseren Modellfit auf als das in der psychologischen Forschung dominierende Standardmodell. Für Letzteres wurde angenommen, dass Maße mathematischer Schülerleistung nur von einer generellen mathematischen Fähigkeit (M) beeinflusst werden. In Studie 2 wurden Schulformunterschiede mit konfirmatorischen Mehrgruppen-Faktormodellen untersucht. Schulformspezifische Mittelwertunterschiede in M waren im Standardmodell wesentlich stärker ausgeprägt als bei M´ im Nested-Faktormodell. Weiterhin wurde eine schulformspezifische Differenzierungshypothese für M´ untersucht. Entgegen der Erwartung konnte diese nur sehr eingeschränkt von den Daten gestützt werden. In Studie 3 wurde die Validität mathematischer Schülerleistung im Hinblick auf soziodemografische und motivationale Schülermerkmale sowie Schulnoten analysiert. Bei Verwendung des Nested-Faktormodells resultierte ein im Vergleich zum Standardmodell wesentlich differenzierteres Befundmuster. So waren Geschlechterunterschiede (zu Gunsten der Jungen) in M´ im Nested-Faktormodell deutlich stärker ausgeprägt als bei M im Standardmodell. Implikationen und Perspektiven der drei Teilstudien werden für die psychologische Forschung, die Lehr-Lernforschung, die Konzeption von Schülerleistungsstudien sowie für die pädagogische Praxis diskutiert. / Three studies investigated mathematics achievement from an individual differences perspective, using data from 29,386 German ninth graders who participated in the 2000 cycle of the OECD’s Programme for International Student Assessment (PISA). In study 1, different structural models of mathematics achievement were derived from structural theories of cognitive abilities, and tested empirically using confirmatory methods. In a nested-factor model, mathematics achievement was specified to be an additive function of specific mathematical ability (M´) and general cognitive ability (g). This model provided a better fit than the standard model that predominates in psychological research, which assumes that measures of mathematical achievement are only influenced by general mathematical ability (M). In study 2, differences between types of schools were analyzed using confirmatory multigroup factor analytic models. Mean differences in M in the standard model were much stronger than in M´ in the nested-factor model. A school-type-specific differentiation hypothesis for M´ was also investigated. Contrary to predictions, the data provided only limited support for this hypothesis. Study 3 analyzed the validity of mathematics achievement with respect to sociodemographic and motivational student characteristics and school grades. The nested-factor model yielded a much more differentiated pattern of results than the standard model. For example, gender differences (in favor of boys) were much more pronounced in M´ in the nested-factor model than in M in the standard model. The implications and future perspectives of studies 1 to 3 are discussed with respect to psychological and educational research, design of large-scale achievement studies, and educational practice.

Theory of Mind (ToM) is the ability to infer others’ mental states and thus to predict their behavior (Perner, 1991). Therefore, ToM is essential for the adequate adjustment of behavior in social situations. ToM can be divided into: 1) cognitive ToM encompassing inferences about intentions and beliefs and 2) affective ToM encompassing inferences about emotions (Shamay-Tsoory, Harari, Aharon-Peretz, & Levkovitz, 2010). Well-functioning skills of both ToM aspects are much-needed in the developmental period of adolescence because in this age phase peer relationships become more important and romantic relationships arise (Steinberg & Morris, 2001). Importantly, affective psychopathological disorders often have their onset in adolescence. ToM development in adolescence might be based on underlying cognitive mechanisms such as the ability to inhibit one’s own thoughts in order to understand another person’s thoughts (Carlson & Moses, 2001). Another possible mechanism relates to functional brain development across adolescence (Blakemore, 2008). Therefore, neurocognitive mechanisms may underlie ongoing ToM development in adolescence. First studies indicate an ongoing behavioral and functional brain development of ToM (e.g. Blakemore, 2008). However, ToM development in adolescence and how this might relate to underlying (neuro)cognitive functions remains largely underexamined. The major aims of the current thesis were first to answer the overall question whether there is an ongoing development of ToM in adolescence. This question relates to both behavioral and functional brain development. As a second major aim, the present work sought to elucidate possible (neuro)cognitive mechanisms of ongoing ToM development across adolescence. Specifically, these cognitive mechanisms might be basic cognitive functions as well as executive functions. Additionally, the present work aimed at exploring potential (neuro)cognitive mechanisms through an integration of both behavioral and functional brain studies. The current experimental work spans three cross-sectional studies investigating adolescents (aged around 12-15 years) and young adults (aged around 18-22 years) to examine for the first time both the behavioral (studies I and II) and functional brain development of ToM (study III) in adolescence and its underlying (neuro)cognitive mechanisms. In all three studies, more complex, advanced ToM tasks were employed to avoid ceiling effects. Study I was aimed at investigating if cognitive and affective ToM continues to develop in adolescence and at exploring if basic cognitive variables such as verbal ability, speed of processing, and working memory capacity underlie such development. Hence, two groups of adolescents and young adults completed tasks of ToM and basic cognitive abilities. Large age effects were revealed on both measures of ToM: adolescents performed lower than adults. These age differences remained significant after controlling for basic cognitive variables. However, verbal ability covaried with performance in affective ToM. Overall, results support the hypothesis of an ongoing development of ToM from adolescence to adulthood on both cognitive and affective aspects. Results may further indicate verbal ability being a basic cognitive mechanism of affective ToM. Study II was designed to further explore if affective ToM, as measured with a dynamic realistic task, continues to develop across adolescence. Importantly, this study sought to explore executive functions as higher cognitive mechanisms of developing affective ToM across adolescence. A large group spanning adolescents and young adults evaluated affective mental states depicted by actors in video clips. Additionally, participants were examined with three subcomponents of executive functions, inhibition, updating, and shifting following the classification of Miyake et al. (2000). Affective ToM performance was positively related to age and all three executive functions. Specifically, inhibition explained the largest amount of variance in age related differences of affective ToM performance. Overall, these results indicate the importance of inhibition as key underlying mechanism of developing an advanced affective ToM in adolescence. Study III set out to explore the functional brain development of affective ToM in adolescence by using functional magnetic resonance imaging (fMRI). The affective ToM measure was the behavioral developmentally sensitive task from study II. An additional control condition consisted of the same emotional stimuli with the instruction to focus on physical information. This study faced methodical challenges of developmental fMRI studies by matching performance of groups. The ventromedial prefrontal cortex (vMPFC) was significantly less deactivated in adolescents in comparison to adults, which might suggest that adolescents seem to rely more on self-referential processes for affective ToM. Furthermore, adolescents compared to adults showed greater activation in the dorsolateral prefrontal cortex (DLPFC) in the control condition, indicating that adolescents might be distracted by the emotional content and therefore needed to focus more on the physical content of the stimulus. These findings suggest affective ToM continues to develop on the functional brain level and reveals different underlying neurocognitive strategies for adolescents in contrast to adults. In summary, the current thesis investigated whether ToM continues to develop in adolescence until young adulthood and explored underlying (neuro)cognitive mechanisms. Findings suggest that there is indeed an ongoing development of both the cognitive and affective aspect of ToM, which importantly contributes to the conceptual debate. Moreover, the second benefit to the debate is to demonstrate how this change may occur. As a basic cognitive mechanism verbal ability and as an executive functioning mechanism inhibition was revealed. Furthermore, neurocognitive mechanisms in form of different underlying neurocognitive strategies of adolescents compared to adults were shown. Taken together, ToM development in adolescence seems to mirror a different adaptive cognitive style in adolescence (Crone & Dahl, 2012). This seems to be important for solving the wealth of socio-emotional developmental tasks that are relevant for this age span.

In today’s globalized business world enterprises face increasing competition and accompanying internal and external threats that challenge their enterprise strategies. Multiple examples of enterprises show that long-lasting strategies need to be progressively overworked in order to secure competitiveness. One key for long-term competitiveness seems to lie in the ability to find a reasonable ratio of strategic stability and change. Neglecting the tension of strategic stability and change can have fatal consequences. Strategic management research increasingly focuses on this challenge. Lately research on ambidexterity and dynamic capability attempts to explain the underlying issues of proactively balancing strategic tensions in dynamic markets. Yet, there remain a couple of questions that – unanswered – limit the explanatory power of recent research models. Because of conceptual ambiguities around the concepts of ambidexterity and dynamic capabilities, until now it remains unclear how a balance between strategic stability and change is reached and managed, and how the underlying strategic decision and strategic management processes at the organizational level look like. To address these open issues, this work develops an alternative framework of strategic ambidexterity. It is defined as a deliberate mechanism to detect, monitor, steer, coordinate and balance stability and change of the enterprise strategy. It argues that enterprises do not deal with strategic stability and change accidently. Quite on the contrary, the enterprises’ key actors are aware of this challenge and have a mechanism in place that allows them to deliberately and continuously employ the right ratio of strategic stability and change. This deliberate mechanism is assumed to create performance differences. High-performing enterprises have a particular setting of the mechanism that distinguishes them from low-performing peers and that secures their long-term competitiveness. In order to empirically test the mechanism a qualitative comparative analysis (QCA) using a sample of 74 mechanical engineering enterprises is performed. As will be shown there are in fact differences between high and low-performing enterprises. The strategic behavior of high-performing enterprises can be classified as Guided Long-Term Inclusive Planning (GLTIP). This work adds new knowledge to the research on ambidexterity and dynamic capabilities and also contributes to the methodological discussion on the analysis of sustainable competitive advantage in today’s globalized and dynamic markets.

In today’s globalized business world enterprises face increasing competition and accompanying internal and external threats that challenge their enterprise strategies. Multiple examples of enterprises show that long-lasting strategies need to be progressively overworked in order to secure competitiveness. One key for long-term competitiveness seems to lie in the ability to find a reasonable ratio of strategic stability and change. Neglecting the tension of strategic stability and change can have fatal consequences. Strategic management research increasingly focuses on this challenge. Lately research on ambidexterity and dynamic capability attempts to explain the underlying issues of proactively balancing strategic tensions in dynamic markets. Yet, there remain a couple of questions that – unanswered – limit the explanatory power of recent research models. Because of conceptual ambiguities around the concepts of ambidexterity and dynamic capabilities, until now it remains unclear how a balance between strategic stability and change is reached and managed, and how the underlying strategic decision and strategic management processes at the organizational level look like. To address these open issues, this work develops an alternative framework of strategic ambidexterity. It is defined as a deliberate mechanism to detect, monitor, steer, coordinate and balance stability and change of the enterprise strategy. It argues that enterprises do not deal with strategic stability and change accidently. Quite on the contrary, the enterprises’ key actors are aware of this challenge and have a mechanism in place that allows them to deliberately and continuously employ the right ratio of strategic stability and change. This deliberate mechanism is assumed to create performance differences. High-performing enterprises have a particular setting of the mechanism that distinguishes them from low-performing peers and that secures their long-term competitiveness. In order to empirically test the mechanism a qualitative comparative analysis (QCA) using a sample of 74 mechanical engineering enterprises is performed. As will be shown there are in fact differences between high and low-performing enterprises. The strategic behavior of high-performing enterprises can be classified as Guided Long-Term Inclusive Planning (GLTIP). This work adds new knowledge to the research on ambidexterity and dynamic capabilities and also contributes to the methodological discussion on the analysis of sustainable competitive advantage in today’s globalized and dynamic markets.:1. Introduction 2. High-performing enterprises, strategic management and dynamic environments – multiple paths of explaining sustainable competitive advantage 3. Toward a multidimensional framework of balancing strategic stability and change: a steering mechanism 4. A comparative configurational analysis of the mechanism of strategic ambidexterity with regard to different performance settings 5. Discussion of results: introducing Guided Long-Term Inclusive Planning (GLTIP) 6. Management implications: GLTIP in action 7. Conclusions, limitations and directions for future research

Theory of Mind (ToM) is the ability to infer others’ mental states and thus to predict their behavior (Perner, 1991). Therefore, ToM is essential for the adequate adjustment of behavior in social situations. ToM can be divided into: 1) cognitive ToM encompassing inferences about intentions and beliefs and 2) affective ToM encompassing inferences about emotions (Shamay-Tsoory, Harari, Aharon-Peretz, & Levkovitz, 2010). Well-functioning skills of both ToM aspects are much-needed in the developmental period of adolescence because in this age phase peer relationships become more important and romantic relationships arise (Steinberg & Morris, 2001). Importantly, affective psychopathological disorders often have their onset in adolescence. ToM development in adolescence might be based on underlying cognitive mechanisms such as the ability to inhibit one’s own thoughts in order to understand another person’s thoughts (Carlson & Moses, 2001). Another possible mechanism relates to functional brain development across adolescence (Blakemore, 2008). Therefore, neurocognitive mechanisms may underlie ongoing ToM development in adolescence. First studies indicate an ongoing behavioral and functional brain development of ToM (e.g. Blakemore, 2008). However, ToM development in adolescence and how this might relate to underlying (neuro)cognitive functions remains largely underexamined. The major aims of the current thesis were first to answer the overall question whether there is an ongoing development of ToM in adolescence. This question relates to both behavioral and functional brain development. As a second major aim, the present work sought to elucidate possible (neuro)cognitive mechanisms of ongoing ToM development across adolescence. Specifically, these cognitive mechanisms might be basic cognitive functions as well as executive functions. Additionally, the present work aimed at exploring potential (neuro)cognitive mechanisms through an integration of both behavioral and functional brain studies. The current experimental work spans three cross-sectional studies investigating adolescents (aged around 12-15 years) and young adults (aged around 18-22 years) to examine for the first time both the behavioral (studies I and II) and functional brain development of ToM (study III) in adolescence and its underlying (neuro)cognitive mechanisms. In all three studies, more complex, advanced ToM tasks were employed to avoid ceiling effects. Study I was aimed at investigating if cognitive and affective ToM continues to develop in adolescence and at exploring if basic cognitive variables such as verbal ability, speed of processing, and working memory capacity underlie such development. Hence, two groups of adolescents and young adults completed tasks of ToM and basic cognitive abilities. Large age effects were revealed on both measures of ToM: adolescents performed lower than adults. These age differences remained significant after controlling for basic cognitive variables. However, verbal ability covaried with performance in affective ToM. Overall, results support the hypothesis of an ongoing development of ToM from adolescence to adulthood on both cognitive and affective aspects. Results may further indicate verbal ability being a basic cognitive mechanism of affective ToM. Study II was designed to further explore if affective ToM, as measured with a dynamic realistic task, continues to develop across adolescence. Importantly, this study sought to explore executive functions as higher cognitive mechanisms of developing affective ToM across adolescence. A large group spanning adolescents and young adults evaluated affective mental states depicted by actors in video clips. Additionally, participants were examined with three subcomponents of executive functions, inhibition, updating, and shifting following the classification of Miyake et al. (2000). Affective ToM performance was positively related to age and all three executive functions. Specifically, inhibition explained the largest amount of variance in age related differences of affective ToM performance. Overall, these results indicate the importance of inhibition as key underlying mechanism of developing an advanced affective ToM in adolescence. Study III set out to explore the functional brain development of affective ToM in adolescence by using functional magnetic resonance imaging (fMRI). The affective ToM measure was the behavioral developmentally sensitive task from study II. An additional control condition consisted of the same emotional stimuli with the instruction to focus on physical information. This study faced methodical challenges of developmental fMRI studies by matching performance of groups. The ventromedial prefrontal cortex (vMPFC) was significantly less deactivated in adolescents in comparison to adults, which might suggest that adolescents seem to rely more on self-referential processes for affective ToM. Furthermore, adolescents compared to adults showed greater activation in the dorsolateral prefrontal cortex (DLPFC) in the control condition, indicating that adolescents might be distracted by the emotional content and therefore needed to focus more on the physical content of the stimulus. These findings suggest affective ToM continues to develop on the functional brain level and reveals different underlying neurocognitive strategies for adolescents in contrast to adults. In summary, the current thesis investigated whether ToM continues to develop in adolescence until young adulthood and explored underlying (neuro)cognitive mechanisms. Findings suggest that there is indeed an ongoing development of both the cognitive and affective aspect of ToM, which importantly contributes to the conceptual debate. Moreover, the second benefit to the debate is to demonstrate how this change may occur. As a basic cognitive mechanism verbal ability and as an executive functioning mechanism inhibition was revealed. Furthermore, neurocognitive mechanisms in form of different underlying neurocognitive strategies of adolescents compared to adults were shown. Taken together, ToM development in adolescence seems to mirror a different adaptive cognitive style in adolescence (Crone & Dahl, 2012). This seems to be important for solving the wealth of socio-emotional developmental tasks that are relevant for this age span.:Abstract 1 1 General Introduction 4 1.1 Concept of ToM: cognitive and affective aspects 7 1.2 ToM Development 8 1.2.1 ToM Development until Adolescence 9 1.2.2 ToM Development in Adolescence 12 1.3 Cognitive Mechanisms 14 1.3.1 Basic Cognitive Functions 15 1.3.2 Executive Functions 17 1.4 Neurocognitive Mechanisms 19 1.4.1 Functional brain development of ToM 20 1.4.2 Integrating behavioral and functional brain studies 21 2 Outline and Central Questions 24 2.1 Does ToM continue to develop in adolescence? 24 2.1.1 Does ToM continue to develop on the behavioral level? 24 2.1.2 Does ToM continue to develop on the level of brain function? 25 2.2 What are (neuro)cognitive mechanisms of ToM development in adolescence? 26 2.2.1 What are basic cognitive and executive functioning mechanisms? 26 2.2.2 Can mechanisms be concluded from the integration of behavioral data and functional brain processes? 26 3 Study I – ToM Development in Adolescence and its Basic Cognitive Mechanisms 28 3.1 Introduction 28 3.2 Method 32 3.2.1 Participants 32 3.2.2 Materials 33 3.3 Results 36 3.3.1 Age Effects 36 3.3.2 Influence of puberty on social cognition 37 3.3.3 Controlling for Basic Cognitive Abilities 39 3.4 Discussion 40 3.4.1 Overview 40 3.4.2 Age differences in social cognition 40 3.4.3 Influence of puberty on social cognition 42 3.4.4 Covariates of age differences in social cognition 42 3.4.5 Conclusions 43 4 Study II – ToM Development in Adolescence and its Executive Functioning Mechanisms 45 4.1 Introduction 45 4.2 Method 49 4.2.1 Participants 49 4.2.2 Materials 49 4.3 Results 52 4.3.1 Decomposing the Age Effect in Affective Theory of Mind 54 4.4 Discussion 55 4.4.1 Overview 55 4.4.2 Conclusions 57 5 Study III – ToM Development in Adolescence and its Neurocognitive Mechanisms 59 5.1 Introduction 59 5.2 Method 61 5.2.1 Participants 61 5.2.2 Stimuli, design and procedure 62 5.2.3 Statistical analysis of behavioral data 65 5.2.4 Functional imaging 65 5.2.5 Statistical analysis of fMRI data 66 5.3 Results 67 5.3.1 Behavioral results 67 5.3.2 fMRI results 68 5.4 Discussion 71 5.4.1 Developmental differences in brain activations 71 5.4.2 Conclusions 74 6 General Discussion 75 6.1 Summary of empirical findings 75 6.2 Discussion and integration of the main empirical findings 76 6.2.1 Continued ToM development in adolescence 76 6.2.2 (Neuro)cognitive mechanisms of ToM development in adolescence 80 6.3 Implications and outlook 89 6.3.1 Current findings and their conceptual fit to present models of ToM 90 6.3.2 Underpinning the concept of cognitive and affective ToM 91 6.3.3 Conceptual and methodical implications of performance matching 92 6.3.4 The role of puberty on ToM 94 6.3.5 Predicting other’s economic behavior 95 6.3.6 Structural brain development 96 6.3.7 Applied perspective 97 6.4 Summary 98 References 99

Geschäftsprozesstechnologien unterstützen dabei, operative Tätigkeiten effizienter und effektiver durchzuführen. In einem sich dynamisch verändernden Umfeld wird es für Organisationen essenziell, diese Technologien gezielt einzusetzen, um durch schnelle Anpassung weiterhin wettbewerbsfähig zu bleiben. Die derzeitige Forschung hat bisher keine Antwort darauf gefunden, wie Organisationen dies trotz ständig wechselnder Umfeldbedingungen und fortschreitender organisationaler Reife durch gezielte Ressourcenallokation erreichen können. Diese Dissertation adressiert diese Forschungslücke, indem untersucht wird, wie organisationale Fähigkeiten mithilfe von Geschäftsprozesstechnologien innerhalb dynamischer Umfelder ausgebildet und erneuert werden können. / Business process technologies help to improve the efficiency and effectiveness of day-to-day operations. Organizations face the challenge of leveraging these technologies to quickly adapt business processes accordingly to cope with different levels of environmental turbulence. From prior research, we know how organizations apply business process technologies and how they affect performance. We do not fully understand how organizations orchestrate related resources based on changing environmental conditions and evolving organizational maturity. This dissertation addresses this research problem and presents research on how to develop and renew organizational capabilities with business process technologies through turbulent environments.

Wir können Mathematikleistungen über fluide Intelligenz (FI) vorhersagen. Der Einfluss von FI auf kognitive Prozesse und neuronale Mechanismen, die mathematischen Fähigkeiten in verschiedenen Teildisziplinen zugrunde liegen, ist jedoch wenig verstanden. Vorliegende Arbeit spezifiziert FI-bezogene Unterschiede in diesen Prozessen und Mechanismen beim Lösen von Geometrie-, Arithmetik- und Algebra-Aufgaben. Mithilfe eines multimethodalen Ansatzes beleuchtet sie das Zusammenspiel zwischen FI, Leistung und Faktoren wie Aufgabenkomplexität, Lernen und Strategiewahl, die kognitive Prozesse und Anforderungen beim Problemlösen beeinflussen. Leistungsunterschiede wurden durch Messung von Reaktionszeiten und Fehlerraten, Strategien durch Augenbewegungsanalyse erfasst. Als Indikator kortikaler Aktivität diente die ereigniskorrelierte (De-)Synchronisation (ERD/ERS) im Alpha-Band. Um kognitive Prozesse zu unterscheiden, haben wir die ERD/ERS im Theta-Band und den Alpha-Unterbändern einbezogen. Beim Lösen unvertrauter geometrischer Analogien zeichnete sich hohe FI durch verstärkte Verarbeitung visuell-räumlicher Informationen zum Repräsentieren von Merkmalszusammenhängen aus. Schüler mit hoher FI passten ihre Strategiewahl den Anforderungen flexibler an. Erstmals konnten wir durch trialweise Identifikation von Strategien FI-bezogene Unterschiede in der neuronalen Effizienz der Strategieausführung feststellen. Beim Lösen vertrauter arithmetischer und algebraischer Terme zeigten sich bei Schülern mit hoher im Vergleich zu Schülern mit durchschnittlicher FI geringere Anforderungen zur Aktualisierung numerischer Repräsentationen und eine bessere Leistung in komplexen Aufgaben. Weitere Analysen legen nahe, dass Schüler mit hoher FI Zusammenhänge in der Aufgabenstruktur besser erkennen und passende Routinen abrufen können. Die Fähigkeit Zusammenhangsrepräsentationen zu bilden könnte demnach ein Schlüsselaspekt zur Erklärung FI-abhängiger Unterschiede in mathematischen Fähigkeiten sein. / Fluid intelligence (FI) is a strong predictor of mathematical performance. However, the impact of FI on cognitive processes and neural mechanisms underlying differences in mathematical abilities across different subdivisions is not well understood. The present work specifies FI-related differences in these processes and mechanisms for students solving geometric, arithmetic, and algebraic problems. We chose a multi-methodological approach to shed light on the interplay between FI, performance, and factors such as task complexity, learning, and strategy selection that influence cognitive processes and task demands in problem-solving. We measured response times and error rates to evaluate performance, eye movements to identify solution strategies, and the event-related (de-)synchronization (ERD/ERS) in the broad alpha band as indicator of general cortical activity. Further, we considered the ERD/ERS in the theta band and the alpha sub-bands to distinguish between associated cognitive processes. For unfamiliar geometric analogy tasks, students with high FI built relational representations based on a more intense processing of spatial information. Strategy analyses revealed a more adaptive strategy choice in response to increasing task demands compared to students with average FI. Further, we conducted the first study identifying strategies and related cortical activity trial-wise and thereby identified FI-related differences in the neural efficiency of strategy execution. For solving familiar arithmetic and algebraic problems, high compared to average FI was associated with lower demands on the updating of numbers leading to a better performance in complex tasks. Further analyses suggest that students with high FI had an advantage to identify the relational structure of the problems and to retrieve routines that match this structure. Thus, the ability to build relational representations might be one key aspect explaining FI-related difference in mathematical abilities.

Nach einem ausführlichem Überblick über den Kenntnisstand der Genetik und Neurowissenschaft von allgemeiner Intelligenz und einer methodischen Anmerkung zur Notwendigkeit der Berücksichtigung latenter Variablen in den kognitiven Neurowissenschaften am Beispiel einer Reanalyse publizierter Ergebnisse wir das am besten etablierte Gehirnkorrelat der Intelligenz, die Gehirngröße, aus evolutionsgenetischer Perspektive neu betrachtet. Schätzungen des Koeffizienten additiv-genetischer deuten an, dass es keine rezente direktionale Selektion auf Gehirngröße gegeben hat, was ihre Validität als Proxy für Intelligenz in evolutionären Studien in Frage stellt. Stattdessen deuten Korrelationen der Gesichtssymmetrie älterer Männer mit Intelligenz und Informationsverarbeitungsgeschwindigkeit an, dass organismusweite Entwicklungsstabilität eine wichtige Grundlage von unterschieden in kognitiven Fähigkeiten sein könnte. Im zweiten Teil dieser Arbeit geht es vornehmlich um die Alterung kognitiver Fähigkeiten, beginnend mit einem allgemeinen Überblick. Daten einer Stichprobe von über 130 Individuen zeigen dann, dass die Integrität verschiedener Nervenbahnen im Gehirn hoch korreliert, was die Extraktion eines Generalfaktors der Traktintegrität erlaubt, der mit Informationsverarbeitungsgeschwindigkeit korreliert. Der einzige Trakt mit schwacher Ladung auf diesem Generalfaktor ist das Splenium des Corpus Callosum, welches mit Veränderungen der Intelligenz über 6 Jahrzehnte korreliert und den Effekt des Bet2 adrenergischem Rezeptorgens (ADRB2) auf diese Veränderung mediiert, möglicherweise durch Effekte auf neuronale Komopensationsprozesse. Schließlich wird auf Basis neuer Analyseverfahren für Magnetresonanzdaten gezeigt, dass vermehrte Eiseneinlagerungen im Gehirn, vermutlich Marker für zerebrale Mikroblutungen, sowohl mit lebenslang stabilen Intelligenzunterschieden als auch mit der altersbedingten Veränderung kognitiver Fähigkeiten assoziiert sind. / After an extensive review of what is known about the genetics and neuroscience of general intelligence and a methodological note emphasising the necessity to consider latent variables in cognitive neuroscience studies, exemplified by a re-analysis of published results, the most well-established brain correlate of intelligence, brain size, is revisited from an evolutionary genetic perspective. Estimates of the coefficient of additive genetic variation in brain size suggest that there was no recent directional selection on brain size, questioning its validity as a proxy for intelligence in evolutionary analyses. Instead, correlations of facial fluctuating asymmetry with intelligence and information processing speed in old men suggest that organism-wide developmental stability might be an important cause of individual differences in cognitive ability. The second half of the thesis focuses on cognitive ageing, beginning with a general review. In a sample of over 130 subjects it has then been found that the integrity of different white matter tracts in the brain is highly correlated, allowing for the extraction of a general factor of white matter tract integrity, which is correlated with information processing speed. The only tract not loading highly on this general factor is the splenium of the corpus callosum, which is correlated with changes in intelligence over 6 decades and mediates the effect of the beta2 adrenergic receptor gene (ADRB2) on cognitive ageing, possibly due to its involvement in neuronal compensation processes. Finally, using a novel analytic method for magnetic resonance data, it is shown that more iron depositions in the brain, presumably markers of a history of cerebral microbleeds, are associated with both lifelong-stable intelligence differences and age-related decline in cognitive functioning.