Objective: In addition to the well-known motor symptoms, Parkinson’s disease (PD) patients also frequently experience disabling non-motor symptoms, such as impulse control disorders (ICDs). The...Show moreObjective: In addition to the well-known motor symptoms, Parkinson’s disease (PD) patients also frequently experience disabling non-motor symptoms, such as impulse control disorders (ICDs). The present study aimed to assess the predictive value of depression and anxiety, and the interaction of these factors with dopaminergic replacement therapy (DRT), for ICD development in de novo PD patients. Methods: Using the Parkinson’s Progression Markers Initiative database, a total of 334 de novo PD patients with a negative ICD screen at baseline (assessed with the Questionnaire for Impulsive‐ Compulsive Disorders short form QUIP-S) were included in the present study. Baseline depression and anxiety were measured by the Geriatric Depression Scale (GDS-15) and the State-Trait-Anxiety Inventory (STAI-Y), respectively. The outcome measures were ICD presence (a positive QUIP-S score) at follow-up visits, and ICD onset duration (time in months from baseline until ICD development). Binominal logistic regression and multiple regression analyses were performed to assess predictors for ICD presence and duration until ICD onset, respectively. Results: In total, 149 participants (44.6%) developed an ICD and the time of ICD onset was on average 34.54 months (SD=24.74) after baseline. Baseline STAI-Y scores were a significant predictor of ICD presence at follow-up visits, and higher scores were associated with an increased likelihood of developing an ICD (OR=1.02, 95% CI 1.00,1.05, p=.036). The first DRT type also significantly predicted ICD incidence, and dopamine agonists were associated with 2.34 higher odds (95% CI 1.45,3.86, p=.001) of developing an ICD, compared to levodopa or other medication types. Both effects were not confounded by age, gender or UPDRS motor score. GDS-15 scores and the interaction terms GDS-15 x DRT type and STAI-Y x DRT type did not significantly predict ICD presence (all ps>.299). None of the investigated factors significantly predicted ICD onset duration (all ps>.091). Implications: The finding that increased anxiety levels in de novo PD patients represent an ICD risk factor highlights the need for early and routine based anxiety screening in these patients. Additionally, clinicians should carefully consider the first choice of DRT, given that patients who received dopamine agonists as their first medication type encountered an increased ICD risk.Show less
Research master thesis | Psychology (research) (MSc)
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Pregnancy leads to volumetric reductions in brain regions involved in Theory of Mind (ToM) tasks. These volumetric reductions appear to be an expression of the woman’s brain preparing itself for...Show morePregnancy leads to volumetric reductions in brain regions involved in Theory of Mind (ToM) tasks. These volumetric reductions appear to be an expression of the woman’s brain preparing itself for motherhood and caregiving. Yet, how pregnancy affects ToM abilities is still largely unknown. The present study investigated how pregnancy affects ToM in primiparous women (i.e., woman who is bearing a first offspring) and whether these changes are predictive of maternal sensitivity. ToM abilities, as assessed through total accuracy scores on the Reading the Mind in the Eyes Task (RMET), were not enhanced at post-pregnancy, compared to pre-pregnancy (H1). Neither did we observe a stronger enhancement in RMET child format performance compared to RMET-adult performance over the course of pregnancy (H2). Moreover, changes in ToM abilities across pregnancy was not a significant predictor of maternal sensitivity at one year postpartum (H3). In conclusion, ToM abilities, as assessed via RMET, did not change over de course of pregnancy. We speculated that the incongruence between our hypotheses and results could potentially be attributed to suboptimal operationalization of ToM abilities. For future studies it may be relevant to include ToM measures that focus more directly on the affective aspect of ToM.Show less
Objective: Multiple sclerosis (MS) is the most common neurodegenerative disease among young adults, of which 40-70% of the patients suffer from cognitive impairment. Currently, there is no...Show moreObjective: Multiple sclerosis (MS) is the most common neurodegenerative disease among young adults, of which 40-70% of the patients suffer from cognitive impairment. Currently, there is no biomarker predicting the cognitive status of MS patients. This study performed a principal component analysis in order to find a disease pattern that can aid in the differentiation of cognitive impairment in MS. Methods: A principal component analysis (PCA) was performed to create a disease pattern based on differences in whole-brain voxel intensities of conventional MRI sequences (T1, T2, and T2- FLAIR) and magnetization transfer (MT)-based MRI of 15 cognitively preserved MS patients (MSCP), 15 impaired patients (MS-CI) and 15 controls. A leave-one-out approach was used to validate the disease patterns between different cognitive performance statuses. Results: None of the conventional MRI sequences nor MT-based MRI were able to find a significant disease pattern for separating MS patients on cognitive status. The frontal cortex, periventricular zone, longitudinal fasciculus, thalamus and brainstem were more severely affected in cognitive impaired MS patients, although significance was not reached. Conclusion: Although the brain patterns created with both conventional MRI sequences and MTbased MRI sequences for evaluating cognitive performance in MS were not significant, the PCA is still a promising technique, when a larger sample size can be included.Show less
Introduction. It has been argued that avoidance behaviour and anhedonia are possible predictors of developing depression in youth with high levels of social anxiety. Method. A community sample of...Show moreIntroduction. It has been argued that avoidance behaviour and anhedonia are possible predictors of developing depression in youth with high levels of social anxiety. Method. A community sample of 237 participants (age 9 - 17 years) participated in the present longitudinal study. During three waves, (over a period of three years) levels of social anxiety, avoidance behaviour, anhedonia and depression were collected using self-report questionnaires. Results. Mediation analyses show that high levels of social anxiety in youth predict an increase of depressive symptoms over time. This was fully mediated by avoidance. However, when controlling for initial depression levels the relation between social anxiety and later depression was no longer significant, though avoidance remained a full mediator. Anhedonia was not a significant mediator in the link between social anxiety and depression. Discussion. It has been argued that socially anxious youth tend to avoid social situations which leads to a relative increase of depression over time. However, socially anxious youth do not experience more anhedonia, while youth with high levels of anhedonia are at risk of developing depression. A recommendation for future research concerns another, better, sequential model to conduct this area. Finally, limitations of the study and therefor suggestions for future research involve a larger and more varied sample as well as including more methods to avoid subjectivity.Show less
Various forms of anxiety, including state and trait cognitive test anxiety, are associated with disruptions in an individual’s cognitive task performance via its detrimental effects on attentional...Show moreVarious forms of anxiety, including state and trait cognitive test anxiety, are associated with disruptions in an individual’s cognitive task performance via its detrimental effects on attentional control capacity of individuals. These disruptions become more evident when the individual is under stress. Frontal EEG theta/beta ratio (TBR) has been suggested to reflect individuals’ baseline attentional control capacity. Furthermore, caffeine has been associated with facilitating or impairing attentional control processes, depending on individuals’ baseline prefrontal cortex functioning. The main goal of this study was to investigate the effects of caffeine on an individual’s working memory (WM) task performance under stress, based on their baseline TBR and anxiety vulnerability. An n-back task was used to assess WM task performance after experimentally induced acute performance stress in a betweensubjects design where the caffeine (200mg) and placebo manipulation was double-blinded, and the sample composed of 120 simulated data. Results of this study are based on synthetic data because of the inability to collect data during covid-19 lockdown. Results showed a moderation of TBR on caffeine: for people with high TBR at baseline (i.e. low attentional control capacity) caffeine boosted WM performance efficiency; while for people with low TBR at baseline (i.e. high attentional control capacity) caffeine disrupted WM performance efficiency. Results provide further support for TBR to be an indicator of attentional control capacity as well as underlining the importance of taking baseline prefrontal functioning of individuals into account when investigating the effects of caffeine on cognitive task performance as previously reported.Show less
Prior research has demonstrated a strong positive relationship between self-efficacy beliefs and pain tolerance. However, the pathways through which self-efficacy beliefs may be manipulated and...Show morePrior research has demonstrated a strong positive relationship between self-efficacy beliefs and pain tolerance. However, the pathways through which self-efficacy beliefs may be manipulated and affect pain tolerance are not clear. The current study aims to examine the effect that self-efficacy beliefs have on pain tolerance ratings, as assessed by a cold-pressor test (CPT). Secondly, whether self-efficacy can be altered through verbal suggestions is examined. Healthy participants (N = 17) were randomly assigned into a low self-efficacy group (Low-SE group) and a high self-efficacy (High-SE group) and participated in a CPT, after self-efficacy manipulation. Differences on pain tolerance and the manipulation check question, across the groups were examined with Analysis of Variance (ANOVA). Baseline measurements of self-efficacy were administered and analysed with ANOVA. Although participants in the High-SE group showed higher pain tolerance ratings (M = 43.23, SD = 19.09) compared to those in the Low-SE group (M = 41.58, SD = 23.36), the difference between the groups was not significant, p = .883. Participants in the High-SE group (M = 5.24, SD = 1.89) had a lower score on the manipulation check question, compared to those in the Low-SE group (M = 5.62, SD = 1.71). However, the difference was not statistically significant, p = .666. No statistically significant baseline differences have been found between the groups. Further research is needed, to determine the mechanisms through which perceived control and affective responses on pain experience may intermediate the relationship between self-efficacy and pain tolerance, while contributing to self-efficacy manipulation.Show less
This study investigates the results of a high intensive residential trauma-focussed therapy programme. The main hypotheses were that (1) PTSD patients with a history of CSA report a clinically...Show moreThis study investigates the results of a high intensive residential trauma-focussed therapy programme. The main hypotheses were that (1) PTSD patients with a history of CSA report a clinically significant decrease in their PTSD symptoms after treatment, and (2) PTSD patients with a history of CSA would profit equally from trauma-focused treatment as PTSD patients without a history of CSA. Methods: Patients were 76 individuals who participated in a five-day treatment program consisting of eye movement desensitization and reprocessing (EMDR), prolonged exposure (PE) sessions, and trauma-sensitive yoga. The severity of PTSD symptoms was assessed with the PCL-5 at pre- and post-treatment, at one-week follow-up, and at a one-month follow-up. Pre-post differences were calculated and compared between the two trauma conditions (i.e., patients with a history of CSA, and no CSA). Results: Treatment resulted in a significant short term decrease of PTSD symptoms, which was mostly maintained at follow-up. Although patients with a history of CSA showed significantly higher PTSD symptom severity at pre- and post-treatment compared to those without a history of CSA, no significant pre-post differences were found between the two groups. Longer term decrease in PTSD symptoms was significant for patients without a history of CSA, but was not strong enough to be significant for patients with a history of CSA. Clinical significance of the treatment was demonstrated for half of the participants. Conclusion: Results suggest that intensive treatment for PTSD might be a possible therapeutic option for PTSD patients with a history of CSA.Show less
Background: Depression symptoms are common in Rheumatoid Arthritis (RA) patients. This could be caused by the limited activities of daily life experienced by RA patients as well as by the...Show moreBackground: Depression symptoms are common in Rheumatoid Arthritis (RA) patients. This could be caused by the limited activities of daily life experienced by RA patients as well as by the inflammation pathways altered by RA which are known to influence depression. Bright light therapy (BLT) has previously shown to be effective to tackle depression caused by an altered circadian rhythm. As a disrupted circadian rhythm is also common in RA patients, BLT might be effective as therapy to treat depression in RA. Objective: The goal of the present study is to examine the effects of BLT on depression and mental health, as well as to explorative examine whether this effect is mediated by changes in circadian rhythmicity in RA patients. Method: This study is a randomized, double-blind, parallel-arm, placebo controlled single center pilot trial study. It consists of 48 RA patients, divided into intervention group with active BLT, and control group with sham BLT. Measurements were taken at three periods: baseline (T0), at the end of the 4-week with BLT (T1), and at follow-up four weeks after BLT (T2). Measurement tools used consisted of a depression scale (HADS) and a mental health scale (RAND 36), as well as the time point of melatonin onset measured by the Dim Light Melatonin Onset test (DLMO). BLT was administered with Luminette glasses which emitted a different color for the intervention group (blue light, to induce circadian phase shift) compared to control group. Results: The results suggest that there is no significant difference with regards to depression, mental health and DLMO between the two groups in the changes between the measurement points from T0 to T1 and from T0 to T2. No significant results were found with regards to the mediating role of DLMO in the relationship between group and depression and mental health. Conclusion: No significant effects of group were found in the present study, with regards to changes in depression, mental health and DLMO, and no mediation effect of the DLMO in the relation between group, depression, and mental health was found. A possible explanation is the low levels of depression reported by the participants at baseline. Further studies are required before disregarding BLT as a potential therapeutic tool to treat depression in RA patients.Show less
Generating emotional brand attachment is a central concern in the current marketing industry. Existing research has shown the high relevance of emotions in consumer–brand relationships. We propose...Show moreGenerating emotional brand attachment is a central concern in the current marketing industry. Existing research has shown the high relevance of emotions in consumer–brand relationships. We propose that the emotion awe makes people feel connected to brands, because awe causes people to feel interconnected. The aim of this research was to investigate the relationship between music, awe and brand attachment. Participants in this online study (N = 199) were randomly divided into four conditions: a music condition, a recall condition, a music and recall condition, and a control condition. We hypothesized that listening to music would induce awe, which in turn would affect brand attachment. Results showed that music did not have a significant effect on awe, but recalling an experience of awe did. Furthermore, awe had a significant effect on brand attachment. Finally, the personality trait Openness to Experience predicted the experience of awe. The implications for these findings, directions for future research and limitations of the current research are discussed.Show less
eHealth could be an effective tool to reduce stress in students. Since eHealth interventions are easy to use and relatively cheap, especially unguided eHealth interventions, it is important to know...Show moreeHealth could be an effective tool to reduce stress in students. Since eHealth interventions are easy to use and relatively cheap, especially unguided eHealth interventions, it is important to know whether students want to take part in an unguided intervention as much as in a guided intervention, and which personal factors play a role in uptake. With this knowledge it might be possible to engage people that would normally not take part in an intervention. In research regarding adherence, perceived social support (PSS) and self-efficacy (SE) appear to play a role. This study focussed on guided and unguided eHealth interventions and the effect of uptake SE and PSS on uptake. We distributed a questionnaire with screenshots of an app amongst students (N = 143). They were randomly assigned to the guided or unguided condition. No effect was found of group on uptake, also PSS had no effect or interaction effect on uptake. Only a direct effect was found of uptake SE on uptake. A possible explanation for the same willingness to start in both groups is the Computers are Social Actors paradigma. Furthermore, uptake SE seems to influence uptake because in case of low levels of SE more support is needed. The results implicate that the type of intervention does not influence uptake, and that low levels of SE are related to lower levels of uptake. Further research should focus on how to increase uptake SE and the personal factors that play a role in uptake.Show less
This study examines whether green advertisements clickability is influenced by the type of green marketing communication messages displayed on the advertisement, and whether this effect is...Show moreThis study examines whether green advertisements clickability is influenced by the type of green marketing communication messages displayed on the advertisement, and whether this effect is moderated by consumers’ level of environmental involvement. A sample of N = 128.830 consumers was exposed to four types of green advertisements for sustainable vegetables: one promoting a personal benefit of purchasing the product, one promoting an environmental benefit, an advertisement that combined both the emotional and functional strategies, and one typical advertisement for the product. The findings reveal that consumers’ level of environmental involvement moderate the effects of functional and emotional appeals. Consumers with higher levels of environmental involvement showed clicked more often compared to low environmentally involved consumers on the functional appeal advertisement. Highly environmentally involved consumers also click more frequently on a functional appeal advertisement, compared to an emotional or combined appeal advertisement. Theoretical and practical implications of these findings are discussed.Show less
To help finding solutions to the growing prevalence of overweight and obesity, this field study examined the human tendency to approach food and its relation to BMI. Using a newly developed...Show moreTo help finding solutions to the growing prevalence of overweight and obesity, this field study examined the human tendency to approach food and its relation to BMI. Using a newly developed behavioral measurement method, food approach tendencies of 89 participants were assessed in states of hunger and satiation. Just as earlier lab studies, our results showed that people had approach tendencies to food. As expected, we also showed that participants with a high BMI had stronger food approach tendencies than participants with a low BMI. However, this study failed to confirm the expectation that the increased tendencies for people with a high BMI were more pronounced in states of satiation than in states of hunger. This failure could be attributed to (a) the fact that participants’ BMI did not vary enough, (b) the general disadvantages of our chosen statistical analysis, (c) contextual factors that we could not control for, or (d) the non-optimal exploitation of hunger state effects. Suggestions for future research are given.Show less
