Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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Both youth with a substance use disorder (SUD) and youth who have experienced adverse childhood experiences (ACEs) show heightened vulnerability to psychopathology. We aimed to quantify the risk of...Show moreBoth youth with a substance use disorder (SUD) and youth who have experienced adverse childhood experiences (ACEs) show heightened vulnerability to psychopathology. We aimed to quantify the risk of comorbid disorders in SUD youth with ACE-history. Additionally, we aimed to examine relations between ACEs, overall household experience, and general distress. We used cross-sectional YIT-study data from interviews with Dutch youth (aged 16-22) upon SUD treatment entry for cannabis, alcohol, or stimulant use. We measured ACE-types experienced up until 15 years of age, past-year DSM-5 disorders, general distress (DASS-21), and overall household experience rating. Logistic regressions quantified relations between ACE sum score and anxiety, depressive, behavior, and any disorder. Higher ACE sum scores related to increased risks for a(n) anxiety (OR = 1.12, highest odds = 2.84; χ2(1) = 6.71, p < .010; Nagelkerke R2 = 0.2), depressive (OR = 1.21, highest odds = 5.43; χ2(1) = 18.11, p < .001; Nagelkerke R2 = 0.6), behavior (OR = 1.20, highest odds = 5.24; χ2(1) = 17.41, p < .001; Nagelkerke R2 = 0.6), and any (OR = 1.25, highest odds = 7.58; χ2(1) = 17.26, p < .001; Nagelkerke R2 = 0.7) disorder. Exploratory analyses revealed that frequency of parental fighting, being hit/abused, getting belittled, emotional neglect, physical neglect, insufficient household income, long parental sickness, and overall household experience positively related to DASS-21. In a hierarchical regression analysis with all ACEs and overall household experience, only emotional neglect related to DASS-21 (B = 3.68, t(373) = 2.41, p = .017). Overall household experience did not improve the model (F(12) = 3.51, p < .001; R2change < .001). In hierarchical regression analyses containing ACE sum score and overall household experience, overall household experience was not uniquely related to DASS-21 (t = -0.22, p = .824; R2change < .01). In conclusion, ACEs relate to comorbid disorders in SUD youth. Our exploratory research suggests that ACE frequency might influence this relation, while overall household experience does not further explain this relation. Further research should investigate which ACE measures (a.o., type, frequency) strongly relate to SUDs and psychopathology and examine improved treatment options.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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This thesis is part of a multi-lab eye-tracking project investigating implicit Theory of Mind (ToM) in toddlers and adults (ManyBabies2). Given the recent number of unsuccessful replications in...Show moreThis thesis is part of a multi-lab eye-tracking project investigating implicit Theory of Mind (ToM) in toddlers and adults (ManyBabies2). Given the recent number of unsuccessful replications in this field, the focus of this thesis lies in investigating the impact of methodological considerations regarding data quality on the obtained results. Specifically, this thesis addresses differences in eye-tracking data quality (accuracy, precision, and data loss) between toddlers and adults. Further, it examines how differences in data quality (precision and data loss) affect the dependent variables in an anticipatory looking (AL) task to measure ToM, and whether the results of the AL task change by adjusting the parameters of a standard fixation classification algorithm (i.e., the Tobii I-VT filter) to account for low data quality. A total of 16 adults and 16 toddlers (N = 32) participated in the ManyBabies2 study at the Leiden University lab. The AL task included two test trials with an ignorance and knowledge condition, during which participants’ looking behavior (first look and proportion differential looking score [DLS]) was measured. The results showed a significant difference in average data quality between toddlers and adults, with toddlers having lower accuracy and precision and higher data loss than adults. Moreover, the results indicated that data loss significantly affects proportion DLS in the ignorance and knowledge condition. However, no differences in AL looking behavior were found between the Tobii I-VT default and adjusted parameters. The findings of this thesis emphasize the need for consistent reporting of data quality. Future research should conduct larger-scale studies to validate and expand upon the findings in this thesis, and focus on refining the fixation classification algorithm parameters of the Tobii I-VT filter to adjust for differences in data quality.Show less
In this thesis, the role of the night in Early Christianity is examined from the first century to 250 CE. What nocturnal worship meant and how early Christians gave meaning to the role of the night...Show moreIn this thesis, the role of the night in Early Christianity is examined from the first century to 250 CE. What nocturnal worship meant and how early Christians gave meaning to the role of the night in their practice, as well as how this was seen and interpreted by their Romans neighbours, is combined in this study to make the case for the inherent nocturnality of the early church, and promote increased research into the topic.Show less
Between 1914 and 1940, the SDAP dominated municipal politics in Amsterdam. Buoyed with the introduction of universal male suffrage in 1917 and the expansion of municipal tax powers in 1920, social...Show moreBetween 1914 and 1940, the SDAP dominated municipal politics in Amsterdam. Buoyed with the introduction of universal male suffrage in 1917 and the expansion of municipal tax powers in 1920, social democratic aldermen such as Wibaut and De Miranda sought to establish a welfare municipality in the capital. Through the municipalisation of basic necessities, housework, and social hygiene, and the provision of care for the sickly, elderly, needy, and unemployed, the alderman hoped to provide for the material welfare and mental well-being of the working-class. Municipal Socialism in Amsterdam was seen as a unique project in the Netherlands. However, the municipal socialist project in Amsterdam was inherently dependent on acquiescence of bourgeois parties in Amsterdam and the confessional national government in The Hague, not to speak of global developments and the world economy. Relativizing the uniqueness of Amsterdam, Rotterdam and The Hague concurrently pioneered different aspects of municipal socialism in the face of similar shortcomings. Amsterdam’s greatest distinction was its incredibly effective advertisement of municipal socialism in publications throughout the interwar period, reinforced by the opposition it inspired in the national bourgeois press. Practically, while Amsterdam’s spending and earnings in municipal socialist fields was generally above average, the capital did not spend or earn significantly more than other social democratic municipalities across all municipal socialist fields. Nor did the capital significantly outperform the two other major municipalities in municipal socialist fields. Thus, while the municipal socialist project in Amsterdam may have financially been above average in the Interwar period, it was not unique, nor significantly different. However, we cannot deny the political and ideational impact of the municipal socialist project in Amsterdam on interwar political thought and post-war public memory.Show less
This thesis deals with binary gender roles in Revolutionary Nationalism in Post-Revolutionary Mexico. By analyzing the first 20 number of the Comic book Adelita y las Guerrillas, the thesis argues...Show moreThis thesis deals with binary gender roles in Revolutionary Nationalism in Post-Revolutionary Mexico. By analyzing the first 20 number of the Comic book Adelita y las Guerrillas, the thesis argues that masculine and feminine gender roles are created in tandem, primarily through the characters Adelita and Juan sin miedo. The thesis argues that whilst portraying progressive gender roles on a superficial level, at its core, the comic book reproduces conservative gender ideology as a part of Revolutionary Nationalism.Show less
Research master thesis | Psychology (research) (MSc)
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Poverty in the UK has increased, particularly after the Covid-19 pandemic. To prevent people from falling into a poverty trap, it is important to understand how financial scarcity affects financial...Show morePoverty in the UK has increased, particularly after the Covid-19 pandemic. To prevent people from falling into a poverty trap, it is important to understand how financial scarcity affects financial decisions involving risks. This topic lacks consensus in the literature with some authors arguing for a tendency towards more risk-taking, while others arguing for more risk aversion. This study posits that the risk tendency is influenced by frames of gains and losses. More specifically, financial scarcity leads to more risky choices in the domain of losses (H1), whereas it leads to less risky choices in the domain of gains (H2). People in financial scarcity tend to experience negative affect that impacts their cognitive systems, leading to more reliance on System 1 thinking, which exacerbates biases, such as the reflection effect. To test the hypotheses an online survey was conducted and 200 participants from the UK were recruited via Prolific Academic. The participants were divided into two groups for the manipulation of financial scarcity using the household task. Half of the participants were in the debts condition (financial scarcity), whereas the other half were not (control). Subsequently, all participants were presented with six risky choices, where they had to choose one of two options (one risky, the other conservative) framed in both gains and losses and three combinations of probabilities. Results from a Generalized Mixed Model showed that the cognitive bias associated with the reflection effect was found to be equally present in everyone and was more pronounced for more extreme probabilities (e.g., 10%/90% and 20%/80%), but not for moderate probabilities (e.g., 40%/60%). Thus, the expected interaction between debts and frames was not confirmed. It is suggested that future studies use an intuitive decision-making manipulation with more extreme probabilities (e.g., 1%/99%), consider a field risk manipulation, an incentivized lottery and the same expected value within and between probabilities at the lottery.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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Prediction-based and repetition-based learning are two learning strategies, differing most profoundly in their depth of processing. In repetition-based learning, students repeat information shortly...Show morePrediction-based and repetition-based learning are two learning strategies, differing most profoundly in their depth of processing. In repetition-based learning, students repeat information shortly after learning it, while in prediction-based learning, students make a prediction before learning the information. This study aims to compare the effectiveness of the two learning strategies for memory recall, as well as consider the influence of age, the magnitude of the prediction errors, and the involved brain areas. It seeks to enhance the educational debate on these learning strategies by uncovering the strategies' mechanisms and guiding educators on their effective use. To accomplish this, 28 young adolescents and 46 young adults were scanned in an MRI scanner while learning numerical facts using both strategies: predicting and repeating. The study explored the influence of strategy, age group, and prediction error on memory recall. Furthermore, it investigated strategy-specific and age-specific differences in the medial temporal lobe (MTL), striatum, anterior cingulate cortex (ACC), and dorsolateral prefrontal cortex (DLPFC). While it was expected that prediction-based learning would result in better learning for both age groups as it requires deeper processing, results showed that adults had improved memory for repetition compared to prediction, whereas adolescents did not show a significant difference between the two learning strategies. Within prediction-based learning, adults showed increased memory for small and large prediction errors, while adolescents only did for large prediction errors. Lastly, among the investigated brain areas, the ACC, which is involved in error detection, showed the most prominent role in prediction-based learning.Show less
Research master thesis | Classics and Ancient Civilizations (research) (MA)
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This thesis explores the way women in selected Euripidean tragedies engage with verbal communication and proposes that this female verbal repertoire can serve as a foundation for a feminist...Show moreThis thesis explores the way women in selected Euripidean tragedies engage with verbal communication and proposes that this female verbal repertoire can serve as a foundation for a feminist interpretation of the respective plays. Female interaction with verbal communication can be separated into three distinct categories: a) silence, b) song, and c) speech. Following this categorization, this thesis firstly delves into specific verses from Medea (259-268) and Hippolytus (710-723, 800-805) to indicate that female tragic silence entails a skillful manipulation of speech. Secondly, verses from Medea (410-430) and two fragments from Hypsipyle (752h 3-9, 759a 80-89) are examined to demonstrate how female tragic song can function as a lyrical form of feminine language. Thirdly, Pasiphae’s apologia (472e 4-12, 34-41) in the Cretans is analyzed to pinpoint how female tragic speech can be rhetorically constructed, serving as a springboard for self-exculpation and female empowerment. Drawing from French feminism and American post-structuralist feminism, this study orchestrates a dialogue between the Euripidean corpus and (post) modern feminist theory and indicates how a reader-oriented approach to the ancient texts can both honor a historically grounded reception of tragedy and suggest how modern audiences can imbue classical tragic texts with fresh meaning.Show less
Research master thesis | Psychology (research) (MSc)
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Within negotiations individuals differ in their motivation to reach certain outcomes over others (outcome orientation). These differences may exaggerate as asymmetrical power dynamics impose...Show moreWithin negotiations individuals differ in their motivation to reach certain outcomes over others (outcome orientation). These differences may exaggerate as asymmetrical power dynamics impose disadvantageous conditions for some individuals within a group. As such restrictions may limit an individual’s ability to realise its interest in certain outcomes, individuals may evoke compensatory mechanisms to alleviate these disadvantages. Building on previous studies (Van Tol & Steinel, 2019), we propose that creative cognitions (e.g., flexibility or originality) may qualify as such potential compensatory mechanism. Consequently, we predict that the effect of individual outcome orientation in relation to an asymmetrical dispersion of power within groups may motivate compensatory engagements in creative behaviours that aim to alleviate the effects of disadvantageous situational constraints. To this end, 150 participants took part in a three-person fictious face-to-face online study. Participants were randomly assigned to either a powerful, powerless, or equal power condition, whilst further differentiations ensured individualistic and collectivistic outcome orientations. Upon reading the instructions, participants completed both a flexibility and an originality task. Results of a 2 (social motive: pro-social vs. pro-self) x 3 (relative power: powerless vs. equal power vs. powerful) ANOVA, as well as a 2 (social motive: pro-social vs. pro-self) x 3 (relative power: powerless vs. equal power vs. powerful) ANCOVA (with individual knowledge about cooking as covariate) revealed non-significant interaction effects for both flexible (ANOVA) and original (ANCOVA) compensation. Across the possible combinations of powerless and powerful, and pro-social and pro-self, participants did not differ in their creativity scores, disconfirming our hypotheses. As these null findings stand in direct contradiction to previous literature, the need for further investigation of creative cognitions in negotiations is highlighted.Show less
Research master thesis | Psychology (research) (MSc)
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Previous studies have highlighted the role of perspective giving in improving intergroup attitudes, particularly among disadvantaged groups. Building on this research, in the current study I...Show morePrevious studies have highlighted the role of perspective giving in improving intergroup attitudes, particularly among disadvantaged groups. Building on this research, in the current study I investigated how the content of perspective giving, focused on issues of inequality or harmony between groups, influences disadvantaged group members’ motivations for collective actions towards social change. I specifically examined this within the context of Cyprus focusing on the Turkish-speaking Cypriot minority (N = 161) in relation to the Greek-speaking Cypriot majority, using a vignette experimental approach. As hypothesized, I found that participants who focused on inequalities with the advantaged outgroup reported greater support for social change, collective action intentions, and change motivation compared to those who focused on commonalities with the outgroup. However, the expected interaction with perspective giving was not found, as it did not make a difference whether the participants gave their perspective to a member of the advantaged outgroup or did not. These findings contribute to our understanding of the complexities of intergroup dynamics and extend on the possible effects of perspective giving on collective action intentions.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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Eating problems and emotional eating in childhood are associated with eating disorders in adolescence. Eating problems and emotional eating can develop due to problems with mood and stress...Show moreEating problems and emotional eating in childhood are associated with eating disorders in adolescence. Eating problems and emotional eating can develop due to problems with mood and stress regulation or appetite regulation. External factors, such as maternal caregiving, can also play a role. Mood, stress and appetite regulation are regulated by the brain but also by the gut. In recent research, the gut has been linked to depression and anxiety, but more research is needed on its role in eating disorders and their precursors. In this study, we explored the link between two precursors of eating disorders, eating problems and emotional eating, and the gut microbiota as well as the moderating role of maternal caregiving. We analysed longitudinal data from the BIBO (Basale Invloeden op de Baby Ontwikkeling) study of Nijmegen university. The data was used to look at whether clusters of bacteria in infancy predict eating problems at 2.5 and 6 years old and emotional eating at 6 and 14 years old. Furthermore, maternal caregiving was added as a moderator to see its role in the potential relationship between the gut and eating problems and emotional eating. Results revealed that there were no significant differences in eating problems (at 2.5 and 6 years old) and emotional eating (at 6 and 14 years old) between the clusters. Furthermore, there was no moderating effect of maternal caregiving on the relationship between microbiota cluster and eating problems and emotional eating. This study suggests that infant microbiota does not predict eating problems and emotional eating in childhood and adolescence in this sample. However, these findings open new paths for future research; with higher taxonomic resolution rather than clusters of bacteria, larger sample sizes, and finally the addition of measures of relevant variables, such as emotion regulation strategies and measures of parent-child relations, such as attachment and parental feeding practices.Show less
Research master thesis | Classics and Ancient Civilizations (research) (MA)
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This thesis focuses on the epigraphic material found in monumental tombs from both Palmyra and the Nabataean kingdom in the ancient Middle East, discussing the use of the various terms for funerary...Show moreThis thesis focuses on the epigraphic material found in monumental tombs from both Palmyra and the Nabataean kingdom in the ancient Middle East, discussing the use of the various terms for funerary architecture in their dialects of Aramaic and Greek. The subject is approached from a sociolinguistic perspective, discussing the socio-cultural implications of the distribution and the use of the vocabulary. The combined evidence shows that the funerary sphere, as the most local sphere visible through the epigraphic evidence, is strongly impacted by social change. Different terms are used for different funerary complexes, depending on their location above or below the surface, or on whether they housed individual or grouped burials. The socio-economic developments in Palmyra and Nabataea in the first centuries of our era led to groups from a new upper middle class gaining interest in expressing their cultural identity through funerary complexes, which were previously reserved for the upper elite. These social developments and their consequences are also partly reflected in the vocabulary used for funerary architecture. This thesis hopes to show what a thorough analytical approach on a specific set of vocabulary can bring to the study of identity in the Roman Near East. Diachronic developments in the Aramaic and Greek vocabulary, divisions across region, tomb type and time will be examined, as they show how the funerary landscape developed in the ancient Middle East from the 1st century BCE up to the 3rd century CE. A database of all attested terms for funerary architecture will be provided and analysed, allowing for a detailed view into the use of these different terms across time and place.Show less
Research master thesis | Archaeology (research) (MA/MSc)
under embargo until 2024-10-19
2024-10-19T00:00:00Z
During the early modern period (1500-1800 CE), Europe was plagued by syphilis, a venereal infection caused by the bacteria Treponema pallidum, resulting in chronic and debilitating symptoms....Show moreDuring the early modern period (1500-1800 CE), Europe was plagued by syphilis, a venereal infection caused by the bacteria Treponema pallidum, resulting in chronic and debilitating symptoms. Desperate to resolve the infection, patients were often subjected to prolonged and extensive treatments with toxic mercury. Unfortunately, osteoarchaeological study of syphilis is challenging due to the limited skeletal visibility of the infection. Moreover, historical evidence is sparse and often influenced by sociocultural stigma attributed to the venereal nature of the disease. This scarcity of data on syphilis in the early modern period has limited more holistic research into the disease and its treatment. Therefore, this study adopted a multidisciplinary approach to investigate syphilis and its treatment at St. Gertrude’s infirmary (1382 - ca. 1611) in Kampen, the Netherlands, where presence of the disease has been previously reported. Human skeletal remains (n=79) were re-examined with a focus on treponemal disease, following the scoring system laid out by Harper et al. (2011). The potential therapeutical use of mercury was investigated by conducting archival research and multiple trace elemental analyses. Using portable X-Ray Fluorescence Spectrometry (pXRF) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), subsamples of the skeletal assemblage were assessed on the presence of mercury in human bone. Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM-EDX) was conducted to assess the potential uptake of mercury in dental calculus on the teeth. Osteoarchaeological study identified several diagnostic cases of treponemal infection at the site (n=5 or 6.33%), as well as a number of cases with lesions suggestive of treponemal disease. This finding demonstrates the influence of treponemal disease, likely attributable to venereal syphilis, at St. Gertrude’s infirmary in Kampen, especially when compared to the prevalence of the disease in human skeletal assemblages from similar Dutch sites. Research into historical archives indicated that mercury was indeed used therapeutically in Kampen during the 18th century. However, it showed no direct evidence for syphilis or mercury treatment at St. Gertrude’s infirmary in the period of interest (1382 – ca. 1611). Unfortunately, elemental analyses revealed no substantial evidence for significantly elevated mercury concentrations, although interesting trends were found. In particular, both pXRF and SEM-EDX analyses did not result in absolute and quantifiable mercury concentrations. While ICP-MS analysis showed absolute concentrations of mercury in a subsample of bone material, interpreting and contextualising these results remains challenging. These observations may be explained by a lack of available mercury treatment in Kampen or a preference for other treatment methods. Nonetheless, this study helps to understand syphilis and its treatment in the early modern Netherlands and provides an evaluation of chemical analyses to detect mercury in archaeological bone.Show less
Research master thesis | Middle Eastern Studies (research) (MA)
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This study seeks to account for the atrocious violence perpetrated by the Assad regime in response to the Syrian uprising that erupted in 2011. Academic scholarship, media reports, and public...Show moreThis study seeks to account for the atrocious violence perpetrated by the Assad regime in response to the Syrian uprising that erupted in 2011. Academic scholarship, media reports, and public opinion tend to understand the state’s violence against its civilians as a resort to exceptional means under exceptional circumstances. This study, in contrast, contends that atrocious violence constitutes a well-established practice, core to this regime’s modus operandi. The study’s objective is to substantiate, illustrate, and critically assess the proposition that atrocious violence perpetrated by the Assad regime is best understood not as a series of incidental exceptional ‘events’ but as a core practice, consisting of a set of sub-practices. The thesis analyzes a selection of primary and secondary sources in answering the research question ‘How to account for the Assad regime’s atrociously violent response to the popular uprising in 2011?’. Primary sources include leaked government documents, legal testimonies, speeches, and memoirs, operationalized with the help of the praxeology research method and a single case-study design. The massacre in Houla in 2012 serves as a primary case study, a narrative anchor from which to assess the strength of the proposition that the regime’s response to the 2011 popular uprising is best understood as the manifestation of a long-standing practice of atrocious state violence sustained by a set of subpractices that effectively make it virtuous across time and space. Specifically, the study identifies the sub-practices of legalizing atrocious violence, narrativizing reality, and consolidating the perpetrator elite.Show less
Research master thesis | Archaeology (research) (MA/MSc)
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Lithics are often one of the few materials from the Paleolithic that withstood the passage of time. Archeologists rely on them when they try to understand what happened in the past. Over the past...Show moreLithics are often one of the few materials from the Paleolithic that withstood the passage of time. Archeologists rely on them when they try to understand what happened in the past. Over the past centuries, lithic research has changed and in the last decennia the use of Machine Learning and 3D geometric morphometric (3DGM) analysis has been explored. In 2021, Archer et al. published a paper in which they explored the possibility of 3DGM analysis. With the help of Machine Learning, their model was trained with an experimental reference collection consisting of Levallois, discoidal and laminar debitage. As a result, the model could classify the technology of 73 – 77 % of the remaining experimental collection correctly. With a traditional analysis, around 20 – 30 % of the flake assemblage is identified. This would indicate that a much larger percentage of the assemblage could be classified with 3DGM analysis. However, this had never been tested on an archeological collection. In this thesis, the late Middle Paleolithic lithics of sublayers EGB and EGC of Quinçay are studied with a focus on flaking technologies. This is done through a traditional analysis consisting of an attribute analysis and a chaîne opératoire analysis and a 3DGM analysis. This is important for two main reasons: 1. Since 3DGM analysis of flaking technologies has never been applied on an archeological collection before, this research might provide valuable insights on how 3DGM analysis can be useful for understanding flaking technologies of archeological lithic collections, 2. The sublayers EGB and EGC of Quinçay have never been studied in detail before, and might provide more insights into the nature of the archeological sequence at Quinçay. Interestingly, the results of the traditional analysis and the 3DGM analysis revealed quite some differences. In the traditional analysis, discoid seemed to be the most common reduction method in the assemblage, this was followed by laminar reduction. However, in the 3DGM analysis, most of the flakes were classified as Levallois flakes. The model seemed to have the most difficulties with recognizing discoid products. The reason for the differences in classification between the traditional analysis and 3DGM analysis, could possibly be result of how the experimental collection was set up and the model was trained. In this thesis, multiple suggestions are proposed that could potentially help with improving the model in such a way that it could be more beneficial when using it on an archeological collection. The advantages and disadvantages that come with 3DGM analysis are also touched upon. By incorporating this innovative approach when studying the late Middle Paleolithic lithics from Quinçay, it is explored how 3DGM analysis can potentially help researchers with the analysis of lithics. As Machine Learning and Artificial Intelligence become more intensively used in the future, it is not unlikely that it will start to play an important role in lithic analysis as well.Show less
Research master thesis | Psychology (research) (MSc)
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Adolescents with ADHD partake in risk-taking behavior (RTB), such as risky driving or unsafe sex, more often than their peers. Because RTB is strongly related to risk perception and RTB takes place...Show moreAdolescents with ADHD partake in risk-taking behavior (RTB), such as risky driving or unsafe sex, more often than their peers. Because RTB is strongly related to risk perception and RTB takes place in a group of peers, it is important to gain a better understanding of risk perception in a social context. First, this study investigated whether adolescents with ADHD are more susceptible to 1) peer influence only and 2) peer influence and presence on a behavioral level. Further, we examined the neural responses to these two social manipulations. We examined whether peer attachment acted as a buffer against susceptibility. Finally, we adopted a continuous approach of ADHD and examined the link between inattention symptoms and hyperactivity-impulsivity symptoms and susceptibility to peer influence and presence. Adolescent boys (ages 13-23) with ADHD (n = 46) and without ADHD (n = 57) performed a risk rating task with a behavioral part and an fMRI-scanner part. The scanner part included highly believable virtual peer influence and peer presence manipulations. For our fMRI analyses we selected regions of interest that are implicated in the social brain (TPJ and dmPFC), the reward processing network (VS, Insula and vmPFC), and the cognitive control network (dlPFC). All adolescents showed equal susceptibility to peer influence only. Similarly, all adolescents showed a higher susceptibility to peer influence and presence. We found no effects on susceptibility of clinical diagnosis, inattention or hyperactivity-impulsivity symptoms or peer attachment. Our fMRI results showed effects in the TPJ. First, peer influence only elicited less activation in the bilateral TPJ for adolescents with ADHD. Second, activity in the left TPJ elicited by peer influence and presence was stronger for adolescents with weaker peer attachment. Together, these findings indicate that peer influence and presence may partly cause increased RTB in adolescence. However, increased RTB in adolescents with ADHD cannot be explained by increased susceptibility peer influence and presence. These findings provide an opportunity to decrease excessive RTB through increasing resistance to peer influence and presence in interventions for adolescents in general.Show less
Research master thesis | Psychology (research) (MSc)
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Novelty can be defined as a motivationally and attentionally salient learning signal. Past research has found benefits of novelty to include increased plasticity and enhanced memory encoding....Show moreNovelty can be defined as a motivationally and attentionally salient learning signal. Past research has found benefits of novelty to include increased plasticity and enhanced memory encoding. Briefly exposing subjects to a novel stimulus or environment in place of an expected threat has also been shown to enhance the extinction process following fear conditioning in both rodents and humans. This is important, as the treatment for trauma-based disorders such as post-traumatic stress disorder (PTSD) has only been demonstrated effective for up to 66% of those affected and a dysfunction in the fear extinction process appears central in the development and continuation of such disorders. The current study explored whether replacing a fear-inducing stimulus with a novel visual stimulus resulted in more effective fear extinction, as quantified using both subjective and objective parameters, namely subjective arousal, and pupil dilation. In addition, a condition with olfactory novelty was included to explore the effects of contextual novelty on preventing the reinstatement of the conditioned fear 24 hours following fear conditioning. The study successfully established fear conditioning using threatening visual stimuli in a classical conditioning paradigm. However, there was no support for novelty-enhanced fear extinction, nor for the benefit of olfactory novelty on the retention of fear extinction 24 hours post-extinction. Rather, an increase in pupil dilation in the context of a novel olfactory environment was found especially in conditions where a fear-inducing unconditioned stimulus had been paired with a novel replacement stimulus, possibly suggesting a contextual novelty-induced fear reinstatement effect.Show less
this thesis compares two important works, Aviezer Tucker's Our Knowledge of the Past and Mark Bevir's The Logic of the History of Ideas, to a novel theory in epistemology, William Talbott's...Show morethis thesis compares two important works, Aviezer Tucker's Our Knowledge of the Past and Mark Bevir's The Logic of the History of Ideas, to a novel theory in epistemology, William Talbott's Learning from our Mistakes. It argues that William Talbott's approach to knowledge can solve longstanding issues within the philosophy of history, particularly pertaining to the normative epistemological question: what should we be believing about the past?Show less
Research master thesis | Middle Eastern Studies (research) (MA)
under embargo until 2024-09-26
2024-09-26T00:00:00Z
This thesis studies on the official letters of Anūshtakīnid Khwārazmshāh dynasty written Rashīd al-Dīn al-Waṭwāṭ (508/1112 - 573/1177), the chief kātib (scribe official) in the court of...Show moreThis thesis studies on the official letters of Anūshtakīnid Khwārazmshāh dynasty written Rashīd al-Dīn al-Waṭwāṭ (508/1112 - 573/1177), the chief kātib (scribe official) in the court of Khwārazmshāh dynasty and explores the concept of loyalty in the letters of Rashīd al-Dīn al-Waṭwāṭ with the main focus on the complexity of social and political networks in Khwārazm before the Mongol invasion. The research question of the thesis is “How did al-Waṭwāṭ reconcile the moralism and real politikal interest inside the relationships of loyalty in his letters?”. The thesis first reviews various academic works and arguments on loyalty into four categories based on historical periods and disciplines and the historical background of al-Waṭwāṭ and Anūshtakīnid Khwārazm, then studies the narrative of al-Waṭwāṭ on three types of relationships of loyalty, which are respectively the relationships of loyalty between the populace and the rulers, the relationships of loyalty between the officials and the rulers, and the relationships of loyalty between rulers.Show less
Research master thesis | Psychology (research) (MSc)
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While the traditional bystander effect literature suggested that the presence of bystanders leads to less help provided to the victims, recent studies that focused on dangerous incidents provided...Show moreWhile the traditional bystander effect literature suggested that the presence of bystanders leads to less help provided to the victims, recent studies that focused on dangerous incidents provided evidence for decreased or even reversed bystander effect in the presence of bystanders. Although previous research proposed that the heightened arousal experienced by bystanders during dangerous incidents with in-group victims leads to increased assistance, empirical evidence supporting this claim remains limited and difficult to be studied with self-report measurements. This study addresses these limitations by employing the biopsychological model of challenge and threat (BPS-CT) to examine empirically the physiological reactions of bystanders. Participants were exposed to vignettes describing dangerous and non-dangerous incidents involving in-group and out-group victims, while their cardiovascular activity and blood pressure were measured. The presence of bystanders was found to have a marginal impact on reducing threat among bystanders, irrespective of the incident's severity. Moreover, in dangerous incidents, the presence of other bystanders and a shared in-group identity with the victim heightened participants' sense of challenge. The findings align with previous meta-analytic evidence, highlighting that bystanders are more likely to intervene in dangerous situations. The results are discussed and possible implications are proposed for designing intervention programs aimed at increasing bystander intervention rates.Show less
