Research master thesis | Psychology (research) (MSc)
under embargo until 2026-01-31
2026-01-31T00:00:00Z
Language control in bilingual speakers involves effectively switching between languages, inhibiting the non-intended language, and continuously monitoring speech errors. It has been a matter of...Show moreLanguage control in bilingual speakers involves effectively switching between languages, inhibiting the non-intended language, and continuously monitoring speech errors. It has been a matter of controversy concerning whether language control operates in a comparable manner to cognitive control processes in non-linguistic domains (domain-general) or if it is exclusive to language processing (domain-specific). Midfrontal theta oscillations have been considered as an index for increased cognitive control, so examining whether a similar midfrontal theta effect is likewise evident in bilingual language will bring new insights to the ongoing debate. This study aimed to explore midfrontal theta oscillations in bilingual control with a specific focus on three fundamental control processes: language switching, inhibitory control, and speech monitoring. We reanalysed the EEG data obtained from two previous language switching studies where Dutch-English bilinguals named pictures based on colour cues. Theta power increase was observed during language switching, specifically in switch trials compared to repeat trials, and this effect was observed in the midfrontal region. Similarly, enhanced midfrontal theta power was observed during error monitoring, specifically when participants failed to select the intended language at a switch, compared to correct responses. However, no midfrontal theta effect was found during inhibitory control, reflected by a missing modulation in switch trials following a short run (i.e., a short sequence of same-language repeat trials) compared to a long run (i.e., a long sequence of same-language repeat trials). These findings largely support the involvement of domain-general cognitive control mechanisms in language control, particularly in language switching and speech monitoring, whereas inhibitory control remains unclear.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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Theory of Mind (ToM) is a central topic in psychology and neuroscience. Nevertheless, debates persist regarding the validity and reliability of ToM measurement. Recent documentation of numerous...Show moreTheory of Mind (ToM) is a central topic in psychology and neuroscience. Nevertheless, debates persist regarding the validity and reliability of ToM measurement. Recent documentation of numerous failed replications in ToM research, involving both children and adults, highlights the need for establishing effective methods for measuring ToM across the lifespan. In response to this challenge, an international multi-lab collaboration named Many Babies 2 (MB2) has been launched, with Leiden University Babylab participating in this project. This thesis discusses preliminary findings related to the 16 adults tested at our lab. Following the MB2 protocol, an eye-tracker attached to a screen recorded participants’ looking behavior (first look [FL] and differential looking scores [DLS]) in an anticipatory looking task. We had two main goals. First, we aimed to find evidence of an automatic and implicit form of ToM in adults, by investigating whether participants’ looking behavior varied depending on a character’s mental state (i.e. whether the character was knowledgeable (condition 1) or ignorant (condition 2) about a specific situation). Contrary to our expectations, neither FL nor DLS differed between the experimental conditions. Second, we examined whether participants’ looking behavior was affected by (a) the selection of the anticipatory period, and (b) participants’ simultaneous activation of a conscious and explicit form of ToM, which had been measured with a debriefing questionnaire. We concluded that none of these factors significantly impacted participants’ looking behavior at a group level. However, FL and DLS of individual participants randomly varied when processed with different anticipatory periods; therefore, further research is needed to determine which anticipatory period minimizes the presence of noise in the data. While recognizing the preliminary nature of our findings, our insights contribute to the ongoing efforts to refine ToM assessment methods, underscoring the importance of addressing challenges in measuring this fundamental aspect of human cognition.Show less
Research master thesis | Psychology (research) (MSc)
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Building on evidence that minority representation increases minorities’ political participation, in my preregistered study, I investigated whether increased racial representation within the climate...Show moreBuilding on evidence that minority representation increases minorities’ political participation, in my preregistered study, I investigated whether increased racial representation within the climate movement causes Americans of color (N = 226) to evaluate the climate movement more positively and to encourage them to partake in climate activism. I tested this by using a 2 x 2 between-subjects design in which representation was manipulated both descriptively (i.e., the presence of people of color) and substantively (i.e., a focus on issues specifically affecting people of color) in a short video about climate activism. The results showed that descriptive representation had a positive, significant effect on evaluation of the movement, but no effects were found for substantive representation nor on climate action behavior. These findings enrich the scientific literature and provide insights on how social movements can become more inclusive, potentially increasing their effectiveness.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Given the practical importance of interpersonal trust in negotiations, scholars have increasingly given attention to the mechanism underlying the effect of trust and possible strategies, such as...Show moreGiven the practical importance of interpersonal trust in negotiations, scholars have increasingly given attention to the mechanism underlying the effect of trust and possible strategies, such as mediation, to handle low trust negotiations. However, research with direct mediator interventions in experimental settings has been rare. We sought to validate previous survey research on the effects of trust and a third-party mediator on negotiation outcomes, negotiator mindset, and perceptions of the negotiation. In our study we looked at the effects of a low trust or a high trust condition on dyadic level, as well as looking at the effect of the presence or absence of a mediator on how dyads negotiated. 38 participants, primarily female students from Leiden University, negotiated in a role-play scenario in a dispute as either a bar owner or a customer. Primary analyses showed no effects for trust on negotiation outcomes, mindset, or satisfaction. Due to severe limitations mediation was not analyzed. Exploratory findings showed that trust increased cooperative efforts and improved relationships, and that secondary agreements, agreements not on prices, were of importance in the negotiations. This study nuances the previously found effects of trust on negotiations and asks for more understanding of the underlying mechanisms and effects of trust.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 | Middle Eastern Studies (research) (MA)
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This thesis provides a detailed case study of the Syrian Archive, the Syrian-led human rights organization that collects, verifies, and contextualizes visual material of human rights violations in...Show moreThis thesis provides a detailed case study of the Syrian Archive, the Syrian-led human rights organization that collects, verifies, and contextualizes visual material of human rights violations in the Syrian conflict. This research draws on diaspora mobilization and social movement theory literature and employs an interpretive approach to thematic analysis to examine how the Syrian Archive contributes to accountability for human rights violations in Syria. The primary data collected are in-depth semi-structured interviews with the Syrian Archive team, in addition to in-depth semi- structured interviews with people working at prominent international organisations in the human rights field. As the findings show, the Syrian Archive contributes to accountability in three ways: by turning digital material into digital evidence, by facilitating political action, and by providing a counter narrative. The interviews with external interviewees from Human Rights Watch, Bellingcat, Amnesty International, and ECCHR reveal the continued impact and mutual dependence that has emerged. The case study of Syrian Archive shows how civil society actors can experiment with new bottom-up possibilities of addressing and pushing for accountability and justice for human rights violations.Show less
Research master thesis | Asian Studies (research) (MA)
open access
This thesis investigates different notions of space and the role they played in processes of colonization and religious conversion in Eastern Indonesia at the beginning of the 19th century....Show moreThis thesis investigates different notions of space and the role they played in processes of colonization and religious conversion in Eastern Indonesia at the beginning of the 19th century. Specifically, it focusses on the 1824 trip of the Dourga which re-instated political and religious ties between the Dutch administration in Ambon and the various island societies in the region. It proposes to treat space as medium of cultural exchange.Show less
Research master thesis | Psychology (research) (MSc)
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Cooperation and competition are important aspects of group behavior that have been well-researched in social psychology, but the relation between these elements has not been investigated to a...Show moreCooperation and competition are important aspects of group behavior that have been well-researched in social psychology, but the relation between these elements has not been investigated to a comparable degree. While competition between groups is known to increase cooperation within groups, the precise magnitude of its influence is not clear. Theoretically-relevant moderators that could influence this relationship have been left largely unexplored, and influential methods of studying cooperation and competition have not been assessed. Therefore, in this pre-registered meta-analysis, we investigated the impact of between-group interactions, including outright between-group competition and situations where groups compare their performance to other groups, on within-group cooperation. We conducted a systematic review of the literature involving economic games that compare cooperation in the presence of an intergroup interaction to cooperation within single groups. We compiled 17 relevant studies which yielded 47 effect sizes. Our multilevel random effects model revealed a small-to-medium, positive effect of intergroup interaction on within-group cooperation (g = 0.505, N = 4187). Confirmatory moderator analyses indicated that males, compared to females, invested more in within-group cooperation during intergroup interactions than in single, isolated groups. Additionally, effects involving intergroup comparison were weaker than effects featuring intergroup competition. Exploratory moderator analyses revealed that several variations in the methods of study impact the effect on within-group cooperation (e.g. deception, decision type, and participant matching). Our findings present compelling meta-analytic evidence that intergroup competition has a reliable impact on cooperation, and raises several opportunities for future research.Show less
Research master thesis | Psychology (research) (MSc)
open access
Bullying victimization is a major public health concern, because victims often experience long-term negative mental health outcomes. Longitudinal brain structure research in children is needed to...Show moreBullying victimization is a major public health concern, because victims often experience long-term negative mental health outcomes. Longitudinal brain structure research in children is needed to understand the possible mechanisms underlying the relation between bullying victimization and negative mental health outcomes. Previous research has shown that the fusiform gyrus, amygdala and vmPFC are impaired in victims. Therefore, this thesis examined the relation between victimization and fusiform gyrus, amygdala and vmPFC volume over time. We hypothesized that victims of bullying, compared to children uninvolved in bullying, would have a larger fusiform gyrus volume and a steeper volume increase. Furthermore, we hypothesized that victims of bullying, compared to children uninvolved in bullying, would have a smaller amygdala and vmPFC volume and a steeper volume decrease. The sample consisted of 156 children (62% female), aged between 7 and 9 years old at baseline, from the Leiden Consortium on Individual Development. At the beginning of the study, the Revised Olweus Bully/Victim Questionnaire was administered to measure bullying victimization and high-resolution structural MRI scans were taken. This was done again two years later. Children were classified as victims if they had been bullied regularly in the past two months. We did not find an effect of victimization on fusiform gyrus, amygdala and vmPFC volume. Future research examining the influence of victimization on both structural and functional brain development is needed to provide further insights, which can help inform the design of interventions to reduce the negative consequences of bullying victimization. The current findings emphasize the importance of protective factors that make a victim’s brain development resilient against victimization. This indicates a need for interventions targeting the development of social-emotional skills or the increase of family support.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
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Coregulation does not seem to come naturally to children with autism spectrum disorder (ASD), putting them at risk of persistent emotional and behavioral dysregulation. However, little is known...Show moreCoregulation does not seem to come naturally to children with autism spectrum disorder (ASD), putting them at risk of persistent emotional and behavioral dysregulation. However, little is known about factors related to the ability of parents to provide coregulatory support and the responsiveness of children with ASD to their attempts. The current study used the state space grid (SSG) methodology to provide insight into the patterns of coregulation between twelve children with ASD (3-6 years) and their parent who spent most time with them (11 mothers, 1 father). In search of characteristics of children and parents that may hinder coregulation, the association with the severity of ASD symptoms and behavioral problems in children, as well as the self-regulation abilities, parenting stress and psychopathology in parents was examined. A free play task was used to elicit interactions between parents and children that were later coded for emotional engagement of both to measure coregulation. Child and parent characteristics were assessed by administration of the Autism Diagnostic Observation Scale (ADOS-2) to children and completion of the Child Behavior Checklist (CBCL), Behavior Rating Inventory of Executive Function for Adults (BRIEF-A), Parenting Stress Questionnaire (OBVL) and Brief Symptom Inventory (BSI) by their parents. Children with ASD generally had emotionally flexible interactions with their parents, indicating that they frequently changed between emotional engagement states when playing together. Their play interactions were mainly positive in nature and all parent-child dyads were able to repair the interaction following negativity or disengagement. More perceived externalizing behavior problems in children was related to less time to reengage in positive interactions with their parents and longer maintained mutual positivity. No association was found for the other characteristics of children and parents. These findings point to the added value of focusing in detail on parent-child interactions for future research and clinical practice.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
closed access
The number of Dutch children who require psychological help keeps growing, and therefore, it is essential to consider their perspective on improving their mental and physical health. The concept of...Show moreThe number of Dutch children who require psychological help keeps growing, and therefore, it is essential to consider their perspective on improving their mental and physical health. The concept of agency contributes to how children experience their health; allowing children to express agency can positively impact their well-being and increase their health (Robertson et al., 2015). The current study aimed to explore and map the role of agency and Emotion Regulation (ER) in children's (10-12 years) view on improving their mental and physical health. This was done using a thematic analysis process of the transcripts. The thematic analysis was conducted on data from previously conducted focus groups on children’s views on health. The results showed several vital themes identified from the data. The central concept of agency was found in children’s constant attempt/wish to change their feelings and thoughts. Within this central concept, three different approaches to ER were identified: “self-talk”, “practical solutions”, and “seeking support”. Especially “self-talk” was often mentioned by the children. The children's different approaches were found to be ways to apply one of three adaptive ER strategies: “reappraisal”, “acceptance”, or “problem-solving”. Children applied these strategies directly or indirectly. Although this study adds knowledge to the understanding of agency in children, much remains to be discovered about agency and its relationship with ER strategies. Follow-up research should be done to gain further insights into the role of agency in improving children’s health, with a particular focus on self-talk and seeking distraction.Show less
Research master thesis | Literary Studies (research) (MA)
open access
This study examines de Digitale Stad, or the Digital City, a pioneering virtual community in the Netherlands (1994-2001), as a metaphorical urban space. Drawing from urban theory, play theory and...Show moreThis study examines de Digitale Stad, or the Digital City, a pioneering virtual community in the Netherlands (1994-2001), as a metaphorical urban space. Drawing from urban theory, play theory and media theory, this thesis analyzes how users navigated and positioned themselves in the virtual realm. By focusing on DDS and the early Web, it sheds light on the Digital City's significance as an experimental space reflecting and influencing the evolving Dutch internet landscape.Show less
Research master thesis | Literary Studies (research) (MA)
open access
This study examines de Digitale Stad, or the Digital City, a pioneering virtual community in the Netherlands (1994-2001), as a metaphorical urban space. Drawing from urban theory, play theory and...Show moreThis study examines de Digitale Stad, or the Digital City, a pioneering virtual community in the Netherlands (1994-2001), as a metaphorical urban space. Drawing from urban theory, play theory and media theory, this thesis analyzes how users navigated and positioned themselves in the virtual realm. By focusing on DDS and the early Web, it sheds light on the Digital City's significance as an experimental space reflecting and influencing the evolving Dutch internet landscape.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Mobile applications with a virtual coach providing real-time relapse-prevention support may be useful to aid smoking cessation as they are easily accessible, cost-effective, and can be utilized...Show moreMobile applications with a virtual coach providing real-time relapse-prevention support may be useful to aid smoking cessation as they are easily accessible, cost-effective, and can be utilized directly in situations where the risk of relapse is high. This study aimed to examine the effect of three types of relapse-prevention support on tobacco craving to inform the development of a mobile application with a virtual coach. The three types of support focused on (A) motivation and self-efficacy; (B) one’s future self and implementation intentions; and (C) identity-related positive self-talk. Secondly, the study aimed to explore how physical nicotine dependence related to the effect of relapse-prevention support on tobacco craving. A virtual reality experiment with a within-participant design was conducted where 25 participants intending to quit smoking were immersed in a virtual high-risk-of-smoking environment. The participants had four conversations in a randomized order with a concept version of a virtual coach on a simulated mobile phone: three conversations containing a type of relapse-prevention support and one neutral conversation. Physical nicotine dependence was measured at baseline and craving was measured after each conversation. Participants indicated that they would find it reasonably difficult to refrain from smoking in the VR environment and sense of presence was sufficient. Results indicated that the relapse-prevention support did not decrease craving compared to neutral contact with the coach. Furthermore, no association was found between physical nicotine dependence and effect of relapse-prevention support. These results stress the need for evaluations of effectiveness in order to inform the further development and improvement of the relapse prevention support prior to finalizing a mobile application with a virtual coach.Show less
