Research master thesis | Psychology (research) (MSc)
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Child social behaviour is indicative of psychosocial functioning. Familial factors, including positive and negative parental characteristics are proposed to be related to child adaptive and...Show moreChild social behaviour is indicative of psychosocial functioning. Familial factors, including positive and negative parental characteristics are proposed to be related to child adaptive and maladaptive social behaviour. The differential susceptibility (DS) theory suggests that the relationship between parental characteristics and child behaviour can only be understood after taking child characteristics into consideration. In this study, we explored the relationship between parental positive and negative affect/social anxiety and child positive shyness and avoidance while taking into account the potential moderating role of child temperament. The sample consisted of children aged 4 to 6 years (N = 68, Age M =5.16; 34 girls) and their primary caregivers. Parents reported their positive and negative affect and their child’s temperament. Child positive shyness and avoidance were observed during a social performance task. Parenting dimensions did not significantly relate to child social behaviour. No significant associations were found between parental positive affect and child observed positive shyness, or between parental negative affect/ social anxiety and child observed avoidance. Child temperament was not found to enhance the relationship between parenting dimensions and child observed behaviour. These non-significant results could be explained by the reflexive nature of inhibitory behaviour, or by methodological aspects of the study.Show less
Research master thesis | Psychology (research) (MSc)
open access
Ecological Momentary Assessment (EMA) is a data collection method that utilizes phone apps to gather data in daily life. EMA has many advantages, such as ecological validity. However, data...Show moreEcological Momentary Assessment (EMA) is a data collection method that utilizes phone apps to gather data in daily life. EMA has many advantages, such as ecological validity. However, data collection protocols are often intense, with multiple measurements per day, which can interrupt participants’ everyday activities and place a burden on them. This can reduce compliance. One way to tackle this is to provide participants with personalized data reports as an intrinsic reward. However, current frameworks to generate such reports are focused on single individuals in treatment, and not suitable for large-scale studies. Here we introduce a software to fill this gap, FRED (Feedback Reports on EMA Data), and showcase FRED by generating reports for 428 participants who took part in the WARN-D study. Participants were followed for 85 consecutive days, and received four daily and one weekly survey, resulting in up to 352 observations. We provided feedback to participants in the form of downloadable HTML-files, which were generated using the R programing environment. Reports included descriptive statistics, timeseries visualizations, and network analyses on selected variables. Furthermore, we assessed participants’ perceptions of the created reports (n=54), who judged reports mostly as understandable, insightful, and that reports resonated well with them. Given that FRED is flexible and can be adjusted to the needs of a particular research project, it provides a good basis to generate large numbers of personalized data reports.Show less
Research master thesis | Psychology (research) (MSc)
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This thesis examined factors that influence citizens’ food waste separation intentions through an extended norm activation model (NAM). Extensions comprised the incorporation of anticipated guilt,...Show moreThis thesis examined factors that influence citizens’ food waste separation intentions through an extended norm activation model (NAM). Extensions comprised the incorporation of anticipated guilt, anticipated disgust, and biodigester information in the model. Citizens of the municipality of Leiden, the Netherlands (N = 168) participated in an experimental survey study. One group of participants completed the survey while keeping their current waste separation options for food waste in mind, other participants received information about small-scale biodigesters and imagined a small-scale biodigester in their neighborhood. Results confirmed that the original NAM is a suitable model for explaining food waste separation intentions. In addition to previous studies, results supported our hypothesis that citizens’ outcome efficacy is positively associated with personal norms. Findings concerning extensions of the NAM were not in line with expectations. Anticipated guilt and anticipated disgust did not mediate the positive relationship between personal norms and behavioral intentions. Furthermore, outcome efficacy was not higher in participants that imagined a small-scale biodigester in their neighborhood in comparison to participants that did not. Implications regarding these findings are discussed.Show less
Research master thesis | Psychology (research) (MSc)
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Purpose. The current study aimed to research the relation between teleworking and distress levels, depressive symptoms, workload, work functioning and need for recovery. Age and gender were further...Show morePurpose. The current study aimed to research the relation between teleworking and distress levels, depressive symptoms, workload, work functioning and need for recovery. Age and gender were further tested as moderators on these relations, and workload was tested as a mediator between telework and distress level, depressive symptoms, work functioning and need for recovery. Methods. A sample of 87 employees working at a Dutch telecom organization were included. The group of employees who exclusively worked at the office (teleworkers; N = 37) was compared to the group of employees who worked remotely some of their time (teleworkers; N = 50) on all outcomes using independent t-tests. The indicators were measured cross-sectionally. Results. There was no significant difference between teleworkers and nonteleworkers in distress level (p = .161, d = 0.33), depressive symptoms (p = .575, d = 0.12), workload (p = .886, d = 0.01), work functioning (p = .266, d = 0.24) and need for recovery (p = .964, d = 0.01). Moreover, age and gender did not have a moderating effect on any of these relations. Results showed lastly that workload was not a significant mediator between telework and all four outcomes. Conclusion. The current study suggests that there is no difference between teleworkers in distress levels, depressive symptoms, workload, work functioning and need for recovery. Also, characteristics of the employees such as gender and age do not seem to relate to relations of telework with these outcomes. Results furthermore suggest that workload does not explain the effects of telework on the included outcomes.Show less
Research master thesis | Psychology (research) (MSc)
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Financial stress is a widespread issue that has a profound impact on the ability to make sound financial decisions. People experiencing financial stress are generally more prone to temporal...Show moreFinancial stress is a widespread issue that has a profound impact on the ability to make sound financial decisions. People experiencing financial stress are generally more prone to temporal discounting: valuing immediate (monetary) outcomes more than future ones. This tendency can prolong the problematic financial situation. In this study, we developed and tested an intervention to help individuals in financial stress increase their focus on their future financial goals. Based on the broaden-and-build theory, which suggests that positive emotions facilitate attentional broadening, we induced either joy or hope in the participants. Our online survey was filled out by 324 UK-participants with varying degrees of financial stress. First, the participants filled in a questionnaire that measured their experienced financial stress. To induce positive emotions, the participants then wrote about personal experiences that either make them feel joy or hope. Finally, they made a series of hypothetical financial decisions. Participants in the gains condition chose between receiving a small amount now, or a larger amount in the future. Participants in the losses condition decided between paying a sum now, or a larger amount later. We hypothesized that, compared to the control condition, temporal discounting would be lower in both the joy and hope condition (1); and that, compared to the control condition, the positive relationship between financial stress and temporal discounting would be weaker in both the joy and hope condition (2). Although our emotion manipulation was successful, linear regression analyses indicated that both hypotheses were not supported. First of all, financial stress and temporal discounting were not positively related in our sample. Additionally, inducing joy and hope did not lessen temporal discounting. We can conclude from this that further research is needed on how temporal discounting can be reduced.Show less
Research master thesis | Psychology (research) (MSc)
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Perceiving and correctly interpreting emotional expressions is one of the most important abilities for social animals’ communication. It determines the majority of social interactions, group...Show morePerceiving and correctly interpreting emotional expressions is one of the most important abilities for social animals’ communication. It determines the majority of social interactions, group dynamics, and cooperation, being highly relevant for an individual’s survival. With the evolutionary implications of understanding emotions, and the phylogenetical closeness between humans and non-human primates, the core mechanisms of this ability have been hypothesized to be shared across closely related species. In the current study, we aimed to find homologies in human processing of different species’ facial expressions using eye-tracking. Introducing a prime-target paradigm, we tested the influences on human’s attention elicited by priming with differently valenced emotional stimuli depicting human and chimpanzee faces. We demonstrated a shift of attention towards the conspecific emotional target picture that was congruent with the valence depicted on the primer picture. We did not find this effect to occur with heterospecific primers, although based on post-hoc valence and arousal ratings, the emotional expressions in chimpanzees were interpreted correctly. Explanations of this finding, as well as implications about the involvement of related emotion processing mechanisms between humans and chimpanzees are discussed. Additional systematic investigations of emotional expressions across species are needed to unravel whether the emotion representation mechanisms can extend to process other species’ faces. Through cross-species investigations, we continue to address the gap of a shared evolutionary ancestry between humans and other animals to ultimately answer the question of “Where emotions come from?”.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Background: The abrupt spread of Covid-19 all over the world created a global crisis and resulted in a pandemic which led to various adverse mental health outcomes. Concordantly, studies reported...Show moreBackground: The abrupt spread of Covid-19 all over the world created a global crisis and resulted in a pandemic which led to various adverse mental health outcomes. Concordantly, studies reported an increasing trend in the prevalence and severity of binge eating and emotional eating symptoms. Aims: To estimate the prevalence and severity rates of binge eating and emotional eating symptoms during the Covid-19 pandemic through systematic review with meta-analysis. Methods: Pre-registered systematic review with meta-analysis (Prospero ID: CRD42022316105). Results: Systematic searches in PubMed and Web of Science (final search date 19th of March, 2022) yielded 27 eligible studies on changes in binge eating and emotional eating prevalence and severity rates during the Covid-19 outbreak (total N = 22.029). An overall increase in the elicited and exacerbated binge eating and emotional eating symptoms during the Covid-19 pandemic was observed (number of studies (k) = 14, r = 0.27, 95% CIs = 0.059 to 0.478). Furthermore, overall 7% of participants reported increases in pooled binge eating and emotional eating behaviours. Conclusions: Our data show a significant increase in the prevalence and severity rates of binge eating and emotional eating during the Covid-19 outbreak. This increase may be expected due to raised emotions of stress, loss of control, fear, ineffectiveness, and boredom during the pandemic. Public health policies and intervention programs for preventing and treating binge eating and emotional eating symptoms should be considered during confinement or related circumstances.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Background: Research has identified psychological factors as important predictors of highly prevelant persistent somatic symptoms (PSS). However, this research is generally not based on primary...Show moreBackground: Research has identified psychological factors as important predictors of highly prevelant persistent somatic symptoms (PSS). However, this research is generally not based on primary care data and general practitioners (GPs) experience difficulties identifying PSS in their patients. Awareness of the psychological risk factors noted in readily accessible electronic medical records (EMRs) might aid GPs with earlier discovery and treatment. Aim: The objective was to examine the predictive value of psychological registrations in primary care for PSS onset. Method: We employed a retrospective longitudinal cohort design. EMR data of Dutch primary care patients were allocated into different subsamples according to registrations of irritable bowel syndrome (IBS), chronic fatigue syndrome (CFS), fibromyalgia (FM), and a combination of these registrations (COMBI) with age and sex-matched non-PSS cohorts. Candidate predictors were registered psychological symptoms, mental health referrals, and psycho-pharmaceuticals registered prior to PSS onset. The relevance of each candidate predictor was determined via L1 regularization in a logistic Lasso regression. The resulting prediction models’ performance was assessed via area under the curve (AUC). Results: The AUC indicated a fair classification performance for IBS (AUC IBS = .77), and good classification performances for CFS, FM, and COMBI (AUC CFS = .82, AUC FM = .88, and AUC COMBI= .87). The IBS-, CFS-, FM-, and COMBI-models, retained a total of 27, 12, 22, and 15 predictors, respectively. The strongest predictor per model was registration of sexual dysfunction for IBS (OR = 4.0), concentration disorder for CFS (OR = 2.4), neurasthenia for FM (OR = 3.0), and concentration disorder for COMBI (OR = 3.8). Neither of these predictors was unique to one specific model. Each final model retained mental health referrals, psycho-pharmaceuticals, and certain psychological symptom registrations as valuable predictors. Based on shared predictors IBS and FM had the closest models while IBS and CFS models were the most dissimilar. Discussion: These findings indicate that several psychological registrations are valuable predictors for onset of IBS, CFS, and/or FM. Therefore, GPs should consider the according predictors when screening for PSS. Future research could examine the comparatively low classification performce for IBS and psychological factors outside of primary care across PSS subtypes.Show less
Research master thesis | Psychology (research) (MSc)
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This study aimed to investigate the effectiveness of a newly developed dynamic screener to assess first year secondary school students’ potential for learning. Participants included 52 children ...Show moreThis study aimed to investigate the effectiveness of a newly developed dynamic screener to assess first year secondary school students’ potential for learning. Participants included 52 children (mean age = 13.14) from different Dutch educational tracks. The dynamic screener consists of the subtests reading, mathematics, working memory, planning, divergent thinking, and inductive reasoning. Each subtest employs a test-training-test design. Based on randomized blocking, half of the children received a graduated prompts training between pre-test and post-test, while the other half did not. On some, but not all, subtests training seems to lead to an increase in performance. Additionally, some constructs measured through the dynamic screener relate to current school performance. This pilot study provides preliminary support to the use of such an instrument to gain more insight into children’s learning potential and instructional needs. Directions for future research are discussed.Show less
Research master thesis | Psychology (research) (MSc)
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The aim of the current study is to investigate the effectiveness of the Mindful with your baby training in a clinical setting and in a preventive setting. The training is an eight-week group-based...Show moreThe aim of the current study is to investigate the effectiveness of the Mindful with your baby training in a clinical setting and in a preventive setting. The training is an eight-week group-based program designed for mothers of babies who cope with parental stress. Mothers in the clinical setting (n = 39) and in the preventive setting (n = 19) completed questionnaires on mindfulness, mindful parenting, parental stress, and parent-child relationship problems at pre-test, post-test, and two-month follow-up. We used multilevel analyses to examine the treatment outcomes. Furthermore, we used multilevel models to explore whether improvements in general and interpersonal aspects of mindfulness (i.e. acting with awareness, listening with full attention) are associated with parent-child relationship problems. The analyses revealed a significant improvement in mindful parenting, and a decline in parental stress and parent-child relationship problems from pre- to post-test (medium to large effect sizes). At follow-up, the effects were maintained for parent-child relationship problems. No differences in effects between the settings were found for any given period. Regarding our exploratory analyses, an improvement in listening with full attention and acting with awareness was not associated with a decline in parent-child relationship problems between pre-test and follow-up. Overall, mothers in the current sample showed positive treatment outcomes after the training, without differences between the preventive and the clinical setting. We suggest that both, mothers who register themselves in a preventive settinag and mothers who are referred to mental health care because of parental stress, can benefit from the training. On the long term, these improvements may contribute to a secure attachment relationship and a safe family environment for the baby.Show less
Research master thesis | Psychology (research) (MSc)
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Background: To alleviate side-effect burden in advanced breast cancer, it is necessary to identify at-risk personality types and effective interventions. Previous research indicates that patients’...Show moreBackground: To alleviate side-effect burden in advanced breast cancer, it is necessary to identify at-risk personality types and effective interventions. Previous research indicates that patients’ pessimism and trait anxiety may be risk factors for experiencing side-effects. To reduce their side-effect burden, optimizing patients’ side-effect expectations is suggested as a novel strategy. Doctor-patient communication strategies, such as expressing empathy (i.e. reassurance of nonabandonment) and explaining psychological mechanisms behind side-effects (i.e. a nocebo explanation), are most promising for optimizing patients’ expectations. In this experimental video-vignette study, we aimed to determine (1) whether clinician-expressed empathy and/or a nocebo explanation is effective in reducing expected side-effect burden, (2) whether generalized pessimism and trait anxiety relate to expected side-effect burden, and (3) whether there is an interaction between the effectiveness of these interventions and these personality characteristics. Methods: Using a two-by-two experimental video-vignette design, 159 cancer patients/survivors and healthy women watched one out of four videos with a nocebo explanation (present/absent) and empathy manipulation (present/absent). The effect of the interventions, the personality characteristics, and the interaction between these two were assessed using regression analyses. Differences between specific (e.g. hair loss) and nonspecific side-effects (e.g. fatigue) were investigated. Results: Clinician-expressed empathy, but not the nocebo explanation (p>.025), was successful in reducing expected side-effect occurrence (p=.008) and intensity (p=.003). Next, pessimistic patients expected side-effects to be more intense (p=.010), which was more profound in predicting the intensity of specific (p=.004), rather than nonspecific side-effects (p=.038). Moreover, results indicate an adverse effect of the nocebo explanation for pessimistic patients, as they expected nonspecific side-effects to be more intense after receiving this intervention (p=.014). Anxious patients expected a higher occurrence of nonspecific side-effects (p=.024), but not of specific side-effects (p=.435). No moderating role was found regarding patients’ anxiety and the effectiveness of the interventions. Conclusions: Short expressions of empathy by an oncologist can improve side-effect expectations. Generalized pessimism may cause patients to be vulnerable to expecting more intense side-effects, and to experiencing adverse effects from the nocebo explanation. Clinical follow-up studies need to investigate whether these results hold in clinical practice, and identify interventions for pessimistic cancer patients.Show less
Research master thesis | Psychology (research) (MSc)
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Video is often regarded as a complete, objective account of events, and therefore we rarely question its validity. However, our interpretation of video can be biased by many factors. Therefore, we...Show moreVideo is often regarded as a complete, objective account of events, and therefore we rarely question its validity. However, our interpretation of video can be biased by many factors. Therefore, we investigated whether we could reduce the overestimating of the objectivity of visual evidence used in police cases. To do that, we showed participants either camera footage of a possible crime, or a textual description of this video. Half of the participants were given a bias warning which asked them to explicitly generate an alternative explanation to their first impression of the evidence (‘consider-the-opposite’ strategy); the other half did not. We compared these four groups on how likely they thought it was that the suspects were guilty, their verdict (guilty/not guilty), and the confidence they had in their judgment. We expected that participants who saw the video would judge the probability of guilt of the suspects as higher than people who read the text, but found the opposite. This could be due to certain aspects of the evidence being more salient in visual or textual form. We explored this using qualitative analysis of participants’ first impressions and alternative explanations of the evidence. Contrary to our expectations, the bias warning did not effectively reduce this difference in guilt judgments between people who saw the video and people who read the text. We did not find that individual differences moderated the effectiveness of the warning, but differences in perspective taking and the perceived objectivity of video did predict the estimated likelihood of guilt. We also did not find that confidence in judgment differed between the four groups. We discuss implications of these findings and give recommendations for future research to further explore how we regard certain visual and textual elements in evidence, and how individual differences play a role in our interpretation of evidence.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Daylight Saving Time (DST) is at its height of controversy in Europe and around the world, as many countries are considering abolishing it. However, little is known about how DST impacts...Show moreDaylight Saving Time (DST) is at its height of controversy in Europe and around the world, as many countries are considering abolishing it. However, little is known about how DST impacts individuals in naturalistic, cognitively-engaging tasks. By using smartphone touchscreen timestamp data from 336 participants in combination with a system identification and impulse response fitting approach, we measured changes in smartphone interactions for 15 days before and 15 days after spring and autumn DST transitions recorded from 2018 to 2021. Our aim was to explore the effect of DST smartphone interactions, including how long DST transitions impact individuals, whether individuals show similarities in their DST responses, and whether age and gender explain differences in DST responses. We found that most individuals were impacted by DST transitions, with a median recovery period of 26 days, almost twice as long as prior estimates. Additionally, hierarchical clustering revealed that some individuals show similarities in their responses to DST, in addition to large inter-individual differences. We also found that differences in the DST response are not explained by age or gender. We propose that large inter-individual differences in responses to DST might be explained by the ability for individuals to self-select their sleep-wake patterns independently of day-night cycles. Additionally, these large inter-individual differences could partly explain the controversy behind DST, as further investigation needs to be made into what causes individuals to respond differently to DST.Show less
Research master thesis | Psychology (research) (MSc)
open access
Previous research has shown that subjective cognitive performance can be enhanced, and that sense of agency can be lowered via verbal suggestion of brain stimulation. Mixed results have been found...Show morePrevious research has shown that subjective cognitive performance can be enhanced, and that sense of agency can be lowered via verbal suggestion of brain stimulation. Mixed results have been found on the effect of placebo stimulation on error-related negativity (ERN) amplitude, which is an implicit outcome measure. This EEG study focused on the role of verbal suggestion and associative learning in eliciting placebo effects in subjective performance, sense of agency, and ERN amplitude. Using a within-subject design, we recorded EEG while participants (n = 19) performed in a simple cognitive task. Participants were told that a sham brain stimulation device would either enhance (placebo condition) or impair (nocebo condition) their cognitive performance. Next, we used a conditioning phase in which we altered the task difficulty according to the experimental block in order to induce the association between task difficulty and proposed stimulation. After this conditioning phase, the task difficulty was equal across conditions. We found increased subjective performance in the nocebo condition, but not the placebo condition, compared to control. We found a lower sense of agency in the placebo condition, but not the nocebo condition, compared to control. Finally, we found no difference in ERN amplitude throughout conditions. These results are not in line with previous research. Our conditioning phase did not work as intended and therefor the results are difficult to interpret. In addition, based on the results of our post-test questionnaire, our verbal suggestion might have been too weak. Future research should try to replicate the earlier results and continue investigating possible (other) implicit outcome measures.Show less
Research master thesis | Psychology (research) (MSc)
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Previous research indicates that the way how video evidence is presented can affect how much intent viewers ascribe suspects. With this between-subjects online study, I investigated whether pausing...Show morePrevious research indicates that the way how video evidence is presented can affect how much intent viewers ascribe suspects. With this between-subjects online study, I investigated whether pausing video evidence leads viewers to ascribe greater premeditated intent to the suspect. Further, I assessed whether this effect may arise because viewers perceive that the suspect had more time to deliberate and/or because the pause makes the deliberation moment more readily available in memory. All participants (N = 169, Mage = 21.95) were shown video evidence of a crime. The video paused either immediately before the crime, far before the crime, or did not pause. Subsequently, they judged the intent of the suspect, and suggested a charge and sentence length that the suspect should serve in detention. Results indicated that pausing video evidence did not lead viewers to ascribe greater intent to the suspect nor to demand a more severe charge. Moreover, pausing video evidence did not lead viewers to perceive that the suspect had more time to deliberate about the crime. However, the pause made the moment of deliberation more readily available in memory. Further, participants who ascribed greater intent to the suspect also demanded longer imprisonment of the suspect. This study provided preliminary insights for policymaking on how to present evidence unbiased for factfinding in court and to ensure fairer legal processes.Show less
Research master thesis | Psychology (research) (MSc)
open access
The recent trend towards gamification could lead to an increase of the number of learning problems that need to be solved through reinforcement learning. It is therefore important that people learn...Show moreThe recent trend towards gamification could lead to an increase of the number of learning problems that need to be solved through reinforcement learning. It is therefore important that people learn how to solve reinforcement learning problems. Understanding which learning strategies people use, the processes behind them, and identifying sub-optimal learning strategies could prove very beneficial for teaching people the best reinforcement learning strategies. This study examines the processes behind reinforcement learning strategies through cognitive modeling. A reinforcement learning model was fitted on human behavior on a reinforcement learning problem. Some people were able to fully solve the problem and others were not. The temporal parameter trajectories of these two groups were compared to each other. The group that solved the problem showed expected results with a lot of learning and exploration at the start and less learning and more exploitation towards the end of the task. The other group started similarly but then started to learn less while exploration remained high. This could indicate that these people would benefit from short learning sessions after which they are able to focus on something else.Show less
Research master thesis | Psychology (research) (MSc)
closed access
Rules regulate society as they help to predict social interactions. Groups, however, do not always abide by rules. Instead, they break them when the conditions are right. Here we hypothesized that...Show moreRules regulate society as they help to predict social interactions. Groups, however, do not always abide by rules. Instead, they break them when the conditions are right. Here we hypothesized that rule abidance behavior is determined by a) an individual choosing another for mutual benefit based on their reputation and b) the social-environmental incentives like fairness and dishonesty. We had three participants building a reputation for their willingness to abide by or break rules. A fourth participant used that information to choose one to three participants, then played several rounds of a dictator game and a die-roll task. Participants were chosen more often when their reputation was in line with environmental incentives, where merely transitioning from one environment to another strengthened that effect. Regulators should therefore ensure the consistency and kinds of environmental incentives that individuals in power positions face across environments for controlling resulting rule abidance behavior.Show less
