Attention-deficit/hyperactivity disorder (ADHD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) are often co-morbid, and their prevalence is increased in the student...Show moreAttention-deficit/hyperactivity disorder (ADHD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) are often co-morbid, and their prevalence is increased in the student population. The dynamics between self-regulation problems and ADHD, MDD, and GAD may reveal insights into the co-occurrence of the three disorders. The present study focused on psychological factors that support or threaten successful self-regulation. Using cross-sectional data, a network analysis was performed based on a sample of 902 students currently enrolled in higher education programs in the Netherlands. The analysis featured 17 commonly studied risk and protective factors associated with all three disorders. The network showed that irritability and impairments in daily functioning were shared problems between ADHD, MDD, and GAD. The network further suggested that impaired cognition and a propensity for procrastination are shared features of ADHD and MDD. ADHD and GAD did not share a direct relationship, diverging from previous assumptions. The findings highlight that the relationship between the disorders may depend on shared vulnerabilities and outcomes that act as bridges in the network. The study illustrates that psychological constructs need to be more clearly defined to move forward when researching co-morbidity beyond the level of symptoms.Show less
Onderzoek naar de classificatieaccuratesse van Alzheimer is belangrijk om de ziekte in de toekomst beter te kunnen behandelen. In deze scriptie werden twee structurele MRI-maten geëvalueerd: grijze...Show moreOnderzoek naar de classificatieaccuratesse van Alzheimer is belangrijk om de ziekte in de toekomst beter te kunnen behandelen. In deze scriptie werden twee structurele MRI-maten geëvalueerd: grijze stofdichtheid (48 predictoren) en subcorticale volumes (14 predictoren). Deze scriptie onderzocht wat de toegevoegde waarde van subcorticale volumes bovenop grijze stofdichtheid is. Hierbij werd verwacht dat I) grijze stofdichtheid accurater was voor de classificatie van Alzheimer dan subcorticale volumes, maar dat II) subcorticale volumes nog wel iets zouden toevoegen aan grijze stofdichtheid. Om dit te onderzoeken, is data gebruikt van 249 participanten afkomstig uit twee verschillende studies. 76 participanten hadden de diagnose Alzheimer en de overige 173 participanten waren cognitief gezonde ouderen. Er zijn drie modellen gebruikt: een model van grijze stofdichtheid (48 predictoren), een model van subcorticale volumes (14 predictoren) en een combinatiemodel van grijze stofdichtheid en subcorticale volumes (62 predictoren). Voor alle modellen is een logistische regressieanalyse met geneste kruisvalidatie uitgevoerd. Het model van grijze stofdichtheid had een AUC-waarde van 0.897 en een MGA-waarde van 0.822. Het model van subcorticale volumes had een AUC-waarde van 0.807 en een MGA-waarde van 0.769. Het gecombineerde model had een AUCwaarde van 0.897 en een MGA-waarde van 0.841. De eerste hypothese werd bevestigd, aangezien grijze stofdichtheid belangrijker was voor de classificatieaccuratesse dan subcorticale volumes. De tweede hypothese kon niet worden bevestigd, aangezien subcorticale volumes weinig tot niets lijken toe te voegen aan grijze stofdichtheid voor de classificatieaccuratesse van Alzheimer. Deze kennis kan gebruikt worden om toekomstige classificatiemodellen van Alzheimer te verbeteren.Show less
Due to the COVID-19 pandemic, many activities and platforms have shifted to the virtual realm, including rituals and ceremonies. When it comes to psychedelic rituals, there are several important...Show moreDue to the COVID-19 pandemic, many activities and platforms have shifted to the virtual realm, including rituals and ceremonies. When it comes to psychedelic rituals, there are several important factors to take into account, such as the setting, dosage, and type of substance consumed. This paper examines the effects of virtual ceremonies on psychedelic experiences. The study utilized an online self-report questionnaire that was sent 1-2 days after the ceremony conducted by retreat company Spinoza. The gathered data were analyzed using thematic qualitative analysis. The categorization and themes were agreed upon by two independent researchers. The themes presented relate to the improvement of mental health and physical comfort along with insightful personal journeys. Further evaluation of the research suggested that the findings provide a general idea about the effects of digital format on the psychedelic experience. It has been found that with digital platforms on psychedelic experiences, individuals can experience clarity of unsolved issues, improved self-regulation, as well as improved emotional and mental states.Show less
Inaction inertia occurs when one is less likely to take an attractive opportunity, after refusing an even more attractive opportunity. In their experiment, van Putten and colleagues (2007) tried to...Show moreInaction inertia occurs when one is less likely to take an attractive opportunity, after refusing an even more attractive opportunity. In their experiment, van Putten and colleagues (2007) tried to decouple the inaction inertia effect by using ambiguous information. Their results yielded that ambiguous information did in fact decouple. However, the authors came to these conclusions by using optional stopping and p-hacking. This influenced the reliability of the results, so we decided to replicate this study, for good research practices and because it can give us valuable insight into how decoupling works when given an attractive offer. We made use of the replication recipe of Brandt and colleagues (2014) to conduct the replication.Show less
Disgust, rooted in human evolutionary history, serves as a vital defense mechanism against pathogens, manifesting in varied behaviors. This paper explores the intricate relationship between disgust...Show moreDisgust, rooted in human evolutionary history, serves as a vital defense mechanism against pathogens, manifesting in varied behaviors. This paper explores the intricate relationship between disgust and visual attention, employing the eye-tracking method. Drawing insights from primate studies, habituation, and human facial expressions, the research aims to address three key questions: Does gaze aversion occur in humans when exposed to disgusting stimuli, extending avoidance behavior into the visual domain? Do individuals exhibit prolonged attention to facial area, indicating a social imperative to assess the risk of pathogen contamination? How does gaze aversion change with repeated exposure to disgust-inducing stimuli? The study employs three conditions, including scenes of feces ingestion in the test condition, to assess total looking time. Results reveal significant gaze aversion towards feces as compared to control conditions, supporting the hypothesis of avoidance behavior. Participants displayed prolonged attention to faces during non-disgusting conditions, challenging assumptions about social necessity for risk assessment. Repeated exposure across trials to disgust-inducing stimuli did not significantly alter gaze behavior, highlighting the nuanced nature of responses to aversive stimuli. Discussion of the findings and implications are also addressed.Show less
Onverwachtse voorvallen kunnen in het dagelijks leven hinder veroorzaken, tenzij er goed op wordt aangepast. Een verminderd aanpassingsvermogen zou dus risico’s met zich mee kunnen brengen. In de...Show moreOnverwachtse voorvallen kunnen in het dagelijks leven hinder veroorzaken, tenzij er goed op wordt aangepast. Een verminderd aanpassingsvermogen zou dus risico’s met zich mee kunnen brengen. In de literatuur zijn vooral onderzoeken te vinden die de invloed van stress op cognitief, maar niet op motorisch aanpassingsvermogen belichten. Om dit gat in de literatuur te vullen, is het van belang om onderzoek te doen naar de invloed van stressniveau op motorisch aanpassingsvermogen. In dit onderzoek deden 80 participanten een VR game en vulden de PSS-10 in om stress te meten. In de VR game moesten participanten objecten vangen en deze in een gat voor zich gooien door controllers te gebruiken. In bepaalde levels was er echter een temporele en/of spatiele asynchronie tussen de avatar en de participant. Het motorisch aanpassingsvermogen werd gemeten door te kijken hoe goed de participanten hierop corrigeerden. De hypothese luidt als volgt: ‘De aanwezigheid van stress is gerelateerd aan een verminderd motorisch aanpassingsvermogen.’ Door middel van een simpele lineaire regressie is aangetoond dat de hypothese verworpen moet worden: stressniveau is geen significante voorspeller van motorisch aanpassingsvermogen (p = .127). Dit onderzoek laat zien dat de VR game mogelijk ingezet kan worden in situaties waarin stress een rol speelt, bijvoorbeeld om af te leiden van stress. Verder toont dit onderzoek dat stress niet altijd een negatieve connotatie zou moeten hebben.Show less
This research aimed to investigate whether food choices can be affected by placebo suggestions and the role of body image satisfaction and Body Mass Index (BMI) in this placebo effect. This study...Show moreThis research aimed to investigate whether food choices can be affected by placebo suggestions and the role of body image satisfaction and Body Mass Index (BMI) in this placebo effect. This study involved 22 participants aged 18-35. In the placebo group, participants received suggestions that a vagus nerve stimulation will decrease their hunger, while the control group received no suggestions. The vagus nerve stimulation was a sham procedure and did not stimulate the nerve. Participants' BMI was calculated followed by measuring body image satisfaction by completing the Body Self Image Questionnaire (BSIQ). Hunger was measured at baseline and post-suggestions. Additionally, food choice was measured with a computer task, in which participants had to choose between healthy and unhealthy food items. The statistical analysis showed no significant differences between the placebo and control groups for food choice (p = 0.56), baseline hunger (p = 0.69), and hunger post suggestions (p = 0.96). Additionally, hunger did not predict healthy food choice (p = 0.89) and body image (p = 0.77) and BMI (p = 0.32) did not moderate the effect of the suggestions on food choice. These results indicate that short suggestions might not be enough to affect hunger and food choices. The lack of effect found might be due to a small sample size and future research should include larger samples and longitudinal research design. Understanding the role of expectations and placebo effects in hunger, can in the future help develop strategies to promote healthier eating.Show less
Background. Picky eating behavior and physical activity are strongly associated with health in children (Karklina et al., 2011). By investigating the associations between shyness, picky eating...Show moreBackground. Picky eating behavior and physical activity are strongly associated with health in children (Karklina et al., 2011). By investigating the associations between shyness, picky eating behavior and physical activity in children and parental stress we could potentially define better intervention programs to prevent health disorders such as cardiovascular disease, diabetes, osteoporosis, anaemia, heart problems and earlier death, by identifying if physical activity, shyness and parental stress are potential areas of treatment. Aims. To investigate (1) if parental stress predicts shyness in ten-year-old children; (2) the association between shyness and picky eating behavior; and (3) the association between shyness and physical activity in ten-year-old children. Methods. A total of 3610 parents of Dutch children (50.6% girls) participated in the study. The mean age of the children was 10.19 (SD=.501; ranging from 8 to 12) Multiple regression analyses were conducted. Results. Shyness was predicted by parental stress (F(4,3601)=44.693, p<.00), picky eating behavior (F(4, 3479) = 12,942, p < .001) and higher levels of shyness were associated with being a boy and older age. Picky eating behavior was predicted by shyness (F(4, 3479) = 60,957, p < .001). Higher levels of picky eating behaviour were associated with lower levels of shyness and having the male gender and the family situation. Higher levels of physical activity were associated with lower levels of shyness and having the male gender. Conclusion. More research must be done with more reliable assessment tools and more universally accepted definitions of the variables. Lower levels of shyness were associated with more picky eating behavior, which is reassuring but our effect sizes and internal consistencies were low. Parental stress and shyness were positively associated with each other. Shyness and physical activity were negatively associated with each other. Since a lack of physical activity has risks such as developing cardiovascular disease, it is important to identify parental stress and shyness in 10-year-olds and provide support and advice to the parents of these 10-year-olds to be able to avert more serious outcomes.Show less
Klimaatverandering wordt versneld door de mens en klimaatvriendelijk gedrag stimuleren kan helpen om de gevolgen van klimaatverandering te verminderen. Kennis over klimaatverandering zorgt ervoor...Show moreKlimaatverandering wordt versneld door de mens en klimaatvriendelijk gedrag stimuleren kan helpen om de gevolgen van klimaatverandering te verminderen. Kennis over klimaatverandering zorgt ervoor dat mensen beter op de hoogte zijn van klimaatverandering en dus wat zij hieraan kunnen doen, maar het werkende mechanisme in de relatie tussen kennis en gedrag is nog onduidelijk. Aan de hand van de Theory of Planned Behavior zou self-efficacy als mediator de relatie tussen kennis en klimaatvriendelijk gedrag kunnen verklaren. Dit is onderzocht bij 428 adolescenten tussen 16 en 24 jaar met een online zelfrapportage vragenlijst over kennis, klimaatvriendelijk gedrag en self-efficacy. De resultaten lieten zien dat zowel de relatie van kennis over klimaatverandering en klimaatvriendelijk gedrag als het indirecte effect via self-efficacy significant en positief zijn. Exploratieve analyses lieten zien dat de significante resultaten niet werden gerepliceerd als er gekeken werd naar specifiek kennis over koolstofdioxide en het broeikaseffect. Echter, er bleek wel een significant en positief direct en indirect verband voor kennis over klimaatverandering en oorzaken hiervan kennis over gevolgen van klimaatverandering. Daarbij bleek een significant positief verband tussen kennis over gevolgen van klimaatverandering en klimaatvriendelijk gedrag wanneer rekening werd gehouden met self-efficacy. Ofwel, deze studie heeft laten zien dat het onderscheid maken in verschillende soorten klimaatkennis belangrijk is als er wordt gekeken naar verbeteren van klimaatvriendelijk gedrag. Door de juiste soort kennis over te dragen, kunnen adolescenten worden gestimuleerd om zich klimaatvriendelijker te gedragen.Show less