Emotions significantly influence our perceptions and interactions with the environment, yet the impact of our emotional states on judging and responding to others remains underexplored. In this... Show moreEmotions significantly influence our perceptions and interactions with the environment, yet the impact of our emotional states on judging and responding to others remains underexplored. In this thesis, I examined how (romantic) attraction influences our attention (Part I), how we judge others’ intentions (Part II), and whether mimicking another facilitates bond formation (Part III). In two empirical chapters, I demonstrate that people have a strong attentional bias towards visual attractiveness and a tendency to indicate interest in establishing a romantic connection to attractive others. In the subsequent empirical chapter, I show that men are more likely to judge women they find attractive as more sexually aroused. Crucially, in a real-life dating study, I show that men who are attracted to another are more likely to assume mutual interest. Further, I introduce a framework suggesting that people align their actions and emotional states with others to foster romantic relationships. The final empirical chapter suggests that mimicking the attraction cues of others enhances bond formation. Overall, this dissertation sheds light on how attractiveness and attraction affect our attention, our social cognition, and the synchronization of actions and emotions, offering insights into the mechanisms underlying romantic connections. Show less
This thesis summarizes a PhD research project, in which we successfully developed and tested a smartphone-based version of the AAT. We used the mobile AAT to show that approach-avoidance tendencies... Show moreThis thesis summarizes a PhD research project, in which we successfully developed and tested a smartphone-based version of the AAT. We used the mobile AAT to show that approach-avoidance tendencies can undergo substantial state-like changes. We further demonstrate how these changes can be systematically related to other state-variables and how important health-related outcomes such as overweight and obesity, can be explained by disruptions of these dynamics. Our findings have broad implications for approach-avoidance research and task-based research in general, as they reveal how smartphones can be used to get insights into the dynamic nature of task outcomes and how (disruptions of) these dynamics can have important real-life consequences. Show less
This dissertation focused on the neural and behavioral mechanisms underlying adolescent learning and mental health in the context of peers and friends. The neuroimaging findings revealed that... Show moreThis dissertation focused on the neural and behavioral mechanisms underlying adolescent learning and mental health in the context of peers and friends. The neuroimaging findings revealed that reward processing for self and peers rely on common reward-related brain regions, whereas a social brain region (TPJ) showed social specificity to observed outcomes for unfamiliar peers compared to friends. Moreover, typically developing adolescents and adolescents with ADHD show neural sensitivity in reward and salience brain regions towards rewards for themselves, friends and peers compared to losses. There were no group differences in neural processing of (vicarious) outcomes between adolescents with and without ADHD, yet a symptom-level approach showed more neural sensitivity for own compared to friends’ losses in individuals with more inattention symptoms. The behavioral findings indicated that adolescents’ learning performance benefitted from observing the choices and outcomes of peers irrespective of the relationship with this peer. The results did not show effects of friendship (quality) and social status on observational and academic learning, but there was a protective effect of friendship quality on internalizing problems. Taken together, these findings highlight adolescence as a period of observational learning opportunities from different types of peers. Adolescence can also serve as a window of opportunity to improve mental health by fostering high-quality friendships. Show less
Two types of financial incentives can help improve healthy lifestyles: carrots (a reward where one can gain something) and sticks (a deposit contract where one can lose something). In a deposit... Show moreTwo types of financial incentives can help improve healthy lifestyles: carrots (a reward where one can gain something) and sticks (a deposit contract where one can lose something). In a deposit contract, participants deposit own money and can lose or earn it back depending on lifestyle changes. We studied the potential of deposit contracts to stimulate a healthy lifestyle.A smartphone app was developed together with the Swiss university ETH Zurich to conduct experimental research into the effects of deposit contracts. In addition, we collaborated with the American company WayBetter to observe the effects of commercially available deposit contracts. Finally, the opinion of people with cardiovascular disease and healthcare professionals regarding financial incentives and deposit contracts for lifestyle change was investigated.The results show that deposit contracts can have strong effects on exercise behavior (daily step counts) in the short term. The results also show that voluntary participation in deposit contracts is limited, but can be increased by doubling the amount deposited and by allowing participants to determine the amount themselves. Finally, healthcare providers think it is a good idea to use financial incentives, but people with cardiovascular disease themselves are skeptical about the use of deposit contracts. Show less
This thesis generated insights into the neural and affective signatures of connectedness between parents and adolescents and between people in general, which is operationalized by responses to eye... Show moreThis thesis generated insights into the neural and affective signatures of connectedness between parents and adolescents and between people in general, which is operationalized by responses to eye contact and empathy. Overall, our findings show that during adolescence, parents are still highly attuned to their child at the neural and affective level. In addition, adolescents report to feel more connected with their parents than with unknown others, although this was not directly reflected in stronger neural responses. Another interesting finding is that making eye contact for a prolonged period generally enhanced the socio-emotional connection between people, both between parents and adolescents and with unknown others. For individuals with a history of CEM and depressed adolescents eye contact is less socially rewarding, however, and does not seem to foster a stronger connectedness with others. Studying the psychobiological underpinnings of affiliative bonding, including the parent-adolescent bond, brings us a step closer to unraveling how such bonds are established and maintained during adolescence. And even more important: Once we know how these bonds are established, we might be better able to modify and repair these bonds in situations in which they for some reason got disrupted. Show less
Despite decades of research from psychology, anthropology, biology and economics, how social preferences arise and vary across contexts remains an open question. In three empirical chapters, this... Show moreDespite decades of research from psychology, anthropology, biology and economics, how social preferences arise and vary across contexts remains an open question. In three empirical chapters, this dissertation addresses this gap using a variety of economic games and neuroimaging techniques that allow for a tractable modeling of cooperation and competition. Overall, findings suggest that while social preferences are linked to neural structure, they can also adapt to environmental factors as well as beliefs about interaction partners. This doctoral thesis shows that interacting with ingroup or outgroup members, taking decisions publicly or privately, and knowing whether we may interact with others again affect our cooperative behavior. These results highlight the importance of understanding how prosociality may be altered and lay the foundations for policy makers to further those social environments that encourage prosocial behavior. Show less
The overarching goal of this dissertation was to investigate parenting processes in relation to affective well-being in families in the daily flow of life from different perspectives (i.e.,... Show moreThe overarching goal of this dissertation was to investigate parenting processes in relation to affective well-being in families in the daily flow of life from different perspectives (i.e., adolescent, mother, father), on different levels (i.e., objective, momentary, and daily), and in a clinical sample (families with an adolescent with a depression) in addition to community samples. Our findings underline the importance of daily parental warmth and criticism of mothers and fathers for adolescents’ well-being. In addition, we showed that adolescents, parents, and their perceptions of parenting influence each other and that becoming more attuned to each other’s intention and needs is essential. Importantly, we consistently demonstrated that not only the extent and direction of the dynamic processes between parenting and affect in daily life differs between, but also within persons and families. This stresses the need for research focusing on individual processes and combining quantitative with qualitative measures. The use of more idiographic approaches would not only enable gaining more insight into these differences between individuals, but also contribute to identifying parenting practices that work for almost all adolescents. This would facilitate the development of interventions combining universal parenting principles with suggestions for tailoring it to individual- or family-specific situations. Show less
This dissertation reveals that sound financial decisions are determined by multiple factors and are germane to both financial satisfaction and financial well-being. The most promising factors to... Show moreThis dissertation reveals that sound financial decisions are determined by multiple factors and are germane to both financial satisfaction and financial well-being. The most promising factors to increase financial satisfaction were financial confidence, future orientation, and perceived behavioural control, and the most promising factors to increase financial well-being were the combination of high objective and high subjective financial knowledge and financial self-efficacy. We also found two observations remarkable. First, not all financial behaviours that could be intuitively regarded as positive were immediately beneficial to financial satisfaction or financial well-being. For example, budgeting and making considered purchases could be unpleasant and, therefore, adversely affect financial well-being in the short term. Likewise, adjusting spending based on changing (financial) circumstances and keeping track of expenses could be painful and, hence, adversely impacted financial satisfaction in the short term. Second, not all control skills that could be expected to help people make sound financial decisions, actually do so. For instance, people with more spending self-control reported working less toward their financial goals. It is possible that these people are so focused on curbing purchase impulses, that they forget what they are doing it for, namely to create financial room to achieve their goals. Show less
This thesis aimed to lay the foundation for a new set of Dutch mental health instruments to measure depression and anxiety in an efficient, reliable, valid, and responsive manner. More specifically... Show moreThis thesis aimed to lay the foundation for a new set of Dutch mental health instruments to measure depression and anxiety in an efficient, reliable, valid, and responsive manner. More specifically, the Dutch-Flemish PROMIS adult v1.0 item banks for Depression and Anxiety were psychometrically evaluated for computerized adaptive test (CAT) administration in the Dutch clinical and general population. CAT is a modern methodology that can be used to develop instruments that measure both efficiently and reliably as only the most appropriate questions are administered, and assessment terminates as soon as sufficient reliability is achieved. For the PROMIS CAT instruments, this was demonstrated in the thesis: measuring depression and anxiety in Dutch persons was highly efficient and reliable. Moreover, the CAT instruments were shown to measure depression and anxiety sufficiently responsive and valid as well. This even includes longitudinal validity, which has barely been studied for other Dutch mental health instruments. Overall, it was concluded that the new instruments are an improvement over available instruments. Therefore, using the PROMIS CAT instruments in clinical practice may lead to more efficient and reliable measurement that supports professionals and patients in evaluating patients' treatment. Show less
This dissertation describes the findings of six studies on mental health problems in the family context, specifically focusing on the associations with the parent-child relationship, parenting... Show moreThis dissertation describes the findings of six studies on mental health problems in the family context, specifically focusing on the associations with the parent-child relationship, parenting behaviors and experiences of childhood maltreatment. The aim is to better understand the risk factors, development and transmission of common psychological problems in order to contribute to prevention and treatment strategies for common psychological problems such as anxiety and depression.Overall, the findings underline the importance of the family context in the development and levels of mental health problems. In addition to the impact of one's own negative parenting experiences, including lack of warmth and experiences of emotional or physical abuse, negative parenting experiences of one's siblings are also associated with elevated anxiety and depressive symptom levels.We also found that externalizing problems of fathers and children have a negative impact on the parent-child interactions. In addition, we found that children with behavioral problems during early adolescence experience harsher parental discipline, even three years later.In the current treatment guidelines for common mental disorders, most therapies focus on the individual. An (additional) systemic approach and considering past and present family relationships in therapy, can be of additional value. For example, supporting families with interventions to improve the parent-child relationship can be helpful in the short and long term. Moreover, (early) treatment of psychological and behavioral problems of the parent or child might be beneficial for all family members. Show less
This PhD research dealt with neurobiological and behavioral aspects of pain. Previous research has demonstrated that pain sensitivity can be worsened as a result of learned negative expectations, a... Show moreThis PhD research dealt with neurobiological and behavioral aspects of pain. Previous research has demonstrated that pain sensitivity can be worsened as a result of learned negative expectations, a phenomenon termed nocebo hyperalgesia –a counterpart to placebo analgesia. This PhD dissertation describes neuroimaging and biobehavioral experimental studies as well as a review and a meta-analysis concerned with such learned effects on pain. The research adds to a growing literature that has been challenging antiquated understandings of pain as a bottom-up process. We conducted a series of biobehavioral studies to further our understanding of how bottom-up pain signaling can be influenced by top-down processing. We examined the types of experiences, such as receiving negative information or experiencing a negative effect first-hand, that may lead to stronger nocebo effects. Behavioral paradigms were used to model real-life pain experiences, through validated methods, novel learning manipulations, as well as a close examination of emotional correlates such as fear. Concurrently, innovative neuroscientific methods –including pharmacological manipulations– were used to examine the biobehavioral underpinnings of learned nocebo responses. Our findings add to the growing knowledgebase from the field of nocebo hyperalgesia, demonstrating that learning by experience can decisively influence the processing and perception of noxious stimuli. Show less
The current dissertation aims to assess the well-being of Emergency Department (ED) nurses and identify (combinations of) job factors related to this. Second, it aims to evaluate the overall... Show moreThe current dissertation aims to assess the well-being of Emergency Department (ED) nurses and identify (combinations of) job factors related to this. Second, it aims to evaluate the overall effectiveness and effective elements of an intervention implementation project conducted in multiple EDs in the Netherlands. Findings show a high prevalence of stress-related outcomes in ED nurses, but also high levels of work engagement and job satisfaction. Worktime demands and aggression/conflict situations have the strongest relationship with exhaustion, whilst work engagement is mostly related to developmental opportunities. Recovery during and outside of work can buffer the impact of patient-related stressful situations. According to a literature review, interventions can effectively prevent/reduce stress-related outcomes in nurses, with person-directed interventions reaching greater short-term effects. Little is known about their longevity and only a limited number of organization-directed studies exist. The current 2,5-year (mostly organization-directed) intervention project, led to improved working conditions but not (yet) to better well-being. Greater effects were found in hospitals with more fitting interventions and were employees felt more informed about and involved in the project. Psychosocial safety climate was positively related to communication, participation and the fit of actions to the risk factors, and as such provides a good starting point for a successful intervention project. Show less
What are the evolutionary roots of emotions? To answer this cardinal question, I study emotions in animals that are evolutionarily close to us: the great apes. In this dissertation, I investigated... Show moreWhat are the evolutionary roots of emotions? To answer this cardinal question, I study emotions in animals that are evolutionarily close to us: the great apes. In this dissertation, I investigated how bonobos, orangutans, and humans perceive emotions by studying three markers of emotion perception: attention, spontaneous mimicry, and implicit associations. Using touchscreen tasks and eye-tracking, I found that bonobos and humans share attentional mechanisms for perceiving their social surroundings. In both species, attention was immediately directed to emotional signals of unfamiliar others (in bonobos) or familiar others (in humans). Bonobos and humans also looked longer at certain emotionally-laden scenes than emotionally-neutral scenes. Subsequently, I studied orangutans: the only apes leading a semi-solitary existence. I found that orangutans show spontaneous mimicry in the form of contagious yawning and self-scratching, contradicting the idea that mimicry only occurs in highly social species. Finally, I created and validated a pictorial version of the implicit association test: a task that can potentially help us uncover whether apes have implicit associations with emotions. The results in this dissertation indicate a common evolutionary origin for attentional mechanisms and mimicry in great apes, including humans, and highlight the importance of considering species-specific characteristics that drive emotion perception. Show less
The overarching goal of this thesis was to examine the behavioral, computational, and neural mechanisms underlying social learning in adolescence. The first aim was to examine developmental... Show moreThe overarching goal of this thesis was to examine the behavioral, computational, and neural mechanisms underlying social learning in adolescence. The first aim was to examine developmental patterns across adolescence of two forms of social learning: (1) learning about other people, specifically, whether they are (un)cooperative and (un)trustworthy, and (2) learning for other people (prosocial learning) to know what actions may benefit or help others. I made use of multiple experimental paradigms based on well-known economic games and/or probabilistic reinforcement learning paradigms to assess these forms of social learning. Secondly, I aimed to examine underlying mechanisms and factors that account for age-related and individual differences in social learning. Applying computational modeling and functional neuroimaging as additional tools contributed to a better understanding of the underlying mechanisms and how these develop across adolescence. The findings in this thesis converge to early-to-mid adolescence as a key developmental period for developing well-adjusted social behaviors, and especially in the cooperative domain there are pronounced improvements. These studies make an important contribution to the literature on social development and learning, and may eventually contribute to interventions targeted at promoting well-adjusted behavior in typically developing adolescents, as well as youth with maladaptive social tendencies. Show less
Physical and sexual abuse during childhood can have long lasting consequences such as posttraumatic stress disorder (PTSD). Prolonged Exposure (PE) is an established and effective guideline... Show morePhysical and sexual abuse during childhood can have long lasting consequences such as posttraumatic stress disorder (PTSD). Prolonged Exposure (PE) is an established and effective guideline treatment for PTSD. Nevertheless, a considerable number of patients drop out from treatment or do not (completely) recover from PTSD during PE. It has been suggested that patients with PTSD resulting from childhood abuse are specifically at risk for suboptimal treatment outcomes. We carried out a randomized controlled trial with 149 patients with childhood abuse-related PTSD comparing PE with two innovations: intensified PE (iPE) and skills training in affective and interpersonal regulation followed by PE (STAIR+PE). We found that all treatments were safe and resulted in large improvements in PTSD symptoms. iPE and STAIR+PE did not improve treatment outcomes of PE, although iPE led to faster symptom improvements. Not all patients benefitted from the allocated treatment, but we found no contra-indications for the treatments. We found that a combination of patient characteristics was predictive of a larger effect size of PTSD symptom improvement in PE and iPE or STAIR+PE. We conclude that the three forms of exposure therapy were effective treatments for patients with childhood abuse-related PTSD. Show less
This thesis describes a dissimilarity-based classification tool, the δ-machine, which gives an alternative way of statistical modeling compared to the conventional ones that directly use predictor... Show moreThis thesis describes a dissimilarity-based classification tool, the δ-machine, which gives an alternative way of statistical modeling compared to the conventional ones that directly use predictor variables. We use the symbol δ, because it is commonly used as a symbol for dissimilarities in multidimensional scaling.In this thesis, we discuss the properties of the δ-machine, and extend the δ-machine from handling continuous predictor variables only to handle different types of predictor variables, including continuous, ordinal, nominal, and binary predictor variables via the two tailored dissimilarity functions. Furthermore, we study the classification performance of the δ-machine in high dimensional data. We propose a Majorization-Minimization algorithm to interpolate new data points coherently into previously constructed classical multidimensional scaling (CMDS) configurations, and use the proposed algorithm in the δ-machine in high dimensional data scenario, where CMDS is applied to reduce the original high dimensional predictor variables. In order to make predictions for new data points, therefore, needs to interpolate them into the constructed CMDS.The δ-machine shows promising predictive performance in general and is able to find informative exemplars/prototypes, which bring extra insights of data. The informative exemplars could be used in the further study. Show less
This thesis investigated the development of emotional functioning in 2-to-6-year-old children with and without autism. Whereas autistic children experienced more challenges in the emotional domain,... Show moreThis thesis investigated the development of emotional functioning in 2-to-6-year-old children with and without autism. Whereas autistic children experienced more challenges in the emotional domain, their emotional abilities improved with age, and developed in similar ways as observed in non-autistic children. On the one hand, this thesis showed that autistic children might deal with emotions in a different way, and they might experience various difficulties when communicating emotions with non-autistic people. One the other hand, it is important to note that the difficulties could be bidirectional. As stated by the “double empathy problem”, non-autistic people may experience the same difficulties when communicating with autistic people. This could be a meaningful direction for future research, investigating emotional communication as a two-way interaction rather than focusing only on how people with autism react to people without autism. Furthermore, this thesis showed that autistic children had the potential to learn and to develop in the emotional domain. Again, this points to the importance of investigating how to create an inclusive social environment, which is not only nurturing for children without autism, but can also benefit the development of children with autism and with other special needs. Show less
This PhD project revealed that the female hormonal status – including OC use – and stress vulnerability – as defined by the MR-haplotype – have practical implications in experimental psychological... Show moreThis PhD project revealed that the female hormonal status – including OC use – and stress vulnerability – as defined by the MR-haplotype – have practical implications in experimental psychological research. Furthermore, incorporation of these variables in models of emotional information processing may be of help in understanding and treating mood disorders in women. Namely, even small biases may affect information processing and may contribute to the resilience or proneness to mood-disorders.Our research was among the first to show that the genetic makeup of healthy women may play a role in the influence of the female hormonal status on emotional information processing. Healthy female MR-haplotype 1/3 carriers may be more prone to distress, and may also be more sensitive to (pharmacological) changes which may counteract or sustain their vulnerability. Consistently, we observed subtle markers of depressogenic side-effects of OC only in MR-haplotype 1/3 carriers. Our findings regarding the MR-haplotypes 2 carriers are generally in line with earlier observations. We observed that MR-haplotype 2 carriers – especially homozygotes – are the less susceptible, more optimistic and more rational individuals, also in ‘unstressed’ conditions. However, stress-related psychopathology is very heterogeneous by nature and proteins from multiple genes are likely to interact in the stress-susceptibility phenotype. Last but not least, we should not ignore that the increased vulnerability of women to mood disorders is the result of a plethora of biological, psychological and sociological factors.OC-users had lower affect variability and reduced sensitivity to interpersonal emotional cues. This may be experienced as either a stabilizing or a blunting effect of OC, perhaps depending on the individual’s appraisal. The lower depression scores of OC-users in our longitudinal study suggests a protective effect of monophasic OC on symptoms of reproductive depression. Future studies should investigate (former) OC-users in larger cohorts including novel users, satisfied users and ‘brand-switchers’ in order to control for the survivor effect. Show less
This dissertation covered several relevant cycles of placebo research with the main aim to optimize placebo effects in medical contexts. Firstly, a literature review described how the immune system... Show moreThis dissertation covered several relevant cycles of placebo research with the main aim to optimize placebo effects in medical contexts. Firstly, a literature review described how the immune system can be impacted by placebo effects and their underlying learning theories. In the following chapter, these learning theories were integrated to form an optimal research design by means of pharmacological conditioning to fit a specific patient group: children with juvenile idiopathic arthritis. Secondly, this dissertation focused on developing placebo information strategies to harness placebo beliefs and educate persons about the relevancy of placebo effects in practice. These insights are valuable because treatment expectations can have a positive or negative effect on treatment outcomes. Finally, insights from placebo learning theories and placebo information strategies were combined in an integrative experimental research design. This research design employed a more ethical form of placebo use because participants were made aware of placebos, called open-label placebos. In this last study we demonstrated that open-label placebo analgesia can be induced by combining learning theories and placebo information strategies. Altogether, this dissertation provided insights in learning mechanisms, communication strategies, and research paradigms that involve the optimization of placebo effects in medical context. Show less
The results described in this thesis support the strong empirical evidence for the effectiveness of CBT-Ef for patients with an eating disorder and a BMI>17.5. When compared to TAU, we found... Show moreThe results described in this thesis support the strong empirical evidence for the effectiveness of CBT-Ef for patients with an eating disorder and a BMI>17.5. When compared to TAU, we found comparable effects on eating disorder psychopathology, however CBT-Ef is superior in enhancing self-esteem with significantly fewer sessions and within a shorter time. We found no support for the hypothesis that more severe self-esteem problems, higher levels of perfectionism, or more interpersonal problems would obstruct long-term improvement and would therefore need extra attention in an extended protocol. A broader use of CBT-Ef in clinical practice could result in more efficient and accessible treatment for patients with an eating disorder. In another study we found COMET to be effective in enhancing self-esteem in patients with an eating disorder. Since we did not find the predictive value of low self-esteem in CBT-E treatment outcome, we suggest to integrate COMET in an eating disorder treatment only when low self-esteem is pronounced and interferes with making progress. Show less
