This thesis explores the role of what has traditionally been considered as neural “noise”, specifically BOLD signal variability and aperiodic neural activity, in human cognitive functions,... Show moreThis thesis explores the role of what has traditionally been considered as neural “noise”, specifically BOLD signal variability and aperiodic neural activity, in human cognitive functions, particularly in metacontrol. The metacontrol model assumes that individuals vary in their cognitive styles between "persistence" and "flexibility." Persistence emphasizes focused goal pursuit, while flexibility allows for easy task switching and consideration of diverse possibilities. Through three empirical studies, this thesis investigates the relationship between two specific forms of neural "noise" – BOLD signal variability and aperiodic neural activity – and metacontrol biases (i.e., persistence vs. flexibility). Chapter 2 emphasizes the importance of resting-state BOLD signal variability in understanding individualized cognitive control styles. Chapter 3 highlights the importance of the aperiodic component of the EEG power spectrum in reflecting demand-specific metacontrol states. Notably, Chapter 4 illuminates the functional significance of aperiodic activity in creative thinking. Overall, the research presented in this thesis highlights the importance of resting-state BOLD signal variability and aperiodic activity in the EEG power spectrum for understanding the neural underpinnings of cognitive functions. Show less
In the realm of cognitive science, the quest to understand cognitive control has persisted for decades. Traditional notions of cognitive control have focused on inhibition through the prefrontal... Show moreIn the realm of cognitive science, the quest to understand cognitive control has persisted for decades. Traditional notions of cognitive control have focused on inhibition through the prefrontal cortex, but this dissertation challenges that perspective with a more comprehensive framework: The Metacontrol State Model (MSM). The MSM proposes that cognitive control emerges from the interplay between two opposing systems – one promoting flexibility and the other promoting persistence. These systems interact to shape our cognitive processing styles, thereby influencing our ability to effectively regulate our actions. This dissertation explores questions such as why individuals exhibit differences in cognitive control capacity and how state-related changes and trait-related predispositions impact cognitive control function. The overarching goal of this dissertation is to empirically test the MSM model and shed light on the factors that influence cognitive control. Through a series of experiments, it seeks to understand how altered states of consciousness, achieved through meditation techniques or serotonergic psychedelics, affect the balance between intentional and habitual processes. Additionally, it examines the extent to which individual trait biases serve as trans-diagnostic markers in various psychopathologies. This work comprises a literature review and six empirical articles. By integrating theory and empirical research, this dissertation takes us on a journey into the intricate world of cognitive control, shaping our understanding of how it influences our lives. Show less
Aims Persistence with direct oral anticoagulants (DOACs) has become a concern in non-valvular atrial fibrillation (NVAF) patients, but whether this affects prognosis is rarely studied. We... Show moreAims Persistence with direct oral anticoagulants (DOACs) has become a concern in non-valvular atrial fibrillation (NVAF) patients, but whether this affects prognosis is rarely studied. We investigated the persistence with oral anticoagulants (OACs) and its association with prognosis among a nationwide cohort of NVAF patients.Methods and results DOAC-naive NVAF patients who started to use DOACs for ischaemic stroke prevention between 2013 and 2018 were included using Dutch national statistics. Persistence with OACs was determined based on the presence of a 100-day gap between the last prescription and the end of study period. In 93 048 patients, 75.7% had a baseline CHA(2)DS(2)-VASc score of >= 2. The cumulative incidence of persistence with OACs was 88.1% [95% confidence interval (CI) 87.9-88.3%], 82.6% (95% CI 82.3-82.9%), 77.7% (95% CI 77.3-78.1%), and 72.0% (95% CI 71.5-72.5%) at 1, 2, 3, and 4 years after receiving DOACs, respectively. Baseline characteristics associated with better persistence with OACs included female sex, age range 65-74 years, permanent atrial fibrillation, previous exposure to vitamin K antagonists, stroke history (including transient ischaemic attack), and a CHA(2)DS(2)-VASc score >= 2. Non-persistence with OACs was associated with an increased risk of the composite outcome of ischaemic stroke and ischaemic stroke-related death [adjusted hazard ratio (aHR) 1.79, 95% CI 1.49-2.15] and ischaemic stroke (aHR 1.58, 95% CI 1.29-1.93) compared with being persistent with OACs.Conclusion At least a quarter of NVAF patients were non-persistent with OACs within 4 years, which was associated with poor efficacy of ischaemic stroke prevention. The identified baseline characteristics may help identify patients at risk of non-persistence. Show less
Aims Persistence with direct oral anticoagulants (DOACs) has become a concern in non-valvular atrial fibrillation (NVAF) patients, but whether this affects prognosis is rarely studied. We... Show moreAims Persistence with direct oral anticoagulants (DOACs) has become a concern in non-valvular atrial fibrillation (NVAF) patients, but whether this affects prognosis is rarely studied. We investigated the persistence with oral anticoagulants (OACs) and its association with prognosis among a nationwide cohort of NVAF patients.Methods and results DOAC-naive NVAF patients who started to use DOACs for ischaemic stroke prevention between 2013 and 2018 were included using Dutch national statistics. Persistence with OACs was determined based on the presence of a 100-day gap between the last prescription and the end of study period. In 93 048 patients, 75.7% had a baseline CHA(2)DS(2)-VASc score of >= 2. The cumulative incidence of persistence with OACs was 88.1% [95% confidence interval (CI) 87.9-88.3%], 82.6% (95% CI 82.3-82.9%), 77.7% (95% CI 77.3-78.1%), and 72.0% (95% CI 71.5-72.5%) at 1, 2, 3, and 4 years after receiving DOACs, respectively. Baseline characteristics associated with better persistence with OACs included female sex, age range 65-74 years, permanent atrial fibrillation, previous exposure to vitamin K antagonists, stroke history (including transient ischaemic attack), and a CHA(2)DS(2)-VASc score >= 2. Non-persistence with OACs was associated with an increased risk of the composite outcome of ischaemic stroke and ischaemic stroke-related death [adjusted hazard ratio (aHR) 1.79, 95% CI 1.49-2.15] and ischaemic stroke (aHR 1.58, 95% CI 1.29-1.93) compared with being persistent with OACs.Conclusion At least a quarter of NVAF patients were non-persistent with OACs within 4 years, which was associated with poor efficacy of ischaemic stroke prevention. The identified baseline characteristics may help identify patients at risk of non-persistence. Show less
Zielinski, G.D.; Rein, N. van; Teichert, M.; Klok, F.A.; Rosendaal, F.R.; Meer, F.J.M. van der; ... ; Lijfering, W.M. 2019
Background In contrast to vitamin K antagonists (VKA), direct oral anticoagulants (DOAC's) are not strictly monitored and dose titrated by anticoagulation clinics in the Netherlands. This may... Show moreBackground In contrast to vitamin K antagonists (VKA), direct oral anticoagulants (DOAC's) are not strictly monitored and dose titrated by anticoagulation clinics in the Netherlands. This may affect drug persistence of atrial fibrillation (AF) patients, whom often require lifelong treatment. Objectives To assess persistence of DOACs and of VKAs in patients with AF. Methods Dispensing data from the Dutch Foundation of Pharmaceutical Statistics were used to monitor persistence of AF patients to DOAC from 1 January 2012-1 April 2016. In addition, we estimated the persistence of AF patients to VKA between 1 January 2004 and 1 January 2012 in data from the Anticoagulation Clinic Leiden. Non-persistence was defined as the cumulative incidence of patients who completely stopped DOAC, switched to another oral anticoagulant or stopped their VKA. Results DOAC users (n = 77 333) were younger than VKA users (n = 10 079; 70 vs 73 years). Non-Persistence to DOAC (ie stopping with any oral anticoagulant) was 34% at 1 and 64% at 4 years, compared to 22% at one and 36% at 4 years for VKA. Approximately a Twenty-five percent of those who had stopped their initial DOAC switched to another anticoagulant (VKA or another DOAC). Multivariable analyses revealed that young age, female sex, no concomitant drug use and non-adherence were predictors for non-persistence of DOAC. Conclusions Persistence to DOAC was low and in line with other observational studies, and higher for VKA. Our results show a clear correlation between age <60 years and worse persistence, as well as with female and non-adherence to DOAC. Show less
Archaeologists have regarded social networks as both the links through which people transmitted information and goods as well as a form of social storage creating relationships that could be drawn... Show moreArchaeologists have regarded social networks as both the links through which people transmitted information and goods as well as a form of social storage creating relationships that could be drawn upon in times of subsistence shortfalls or other deleterious environmental conditions. In this article, formal social network analytical (SNA) methods are applied to archaeological data from the late pre-Hispanic North American Southwest to look at what kinds of social networks characterized those regions that were the most enduring versus those that were depopulated over a 250-year period (A.D. 1200–1450). In that time, large areas of the Southwest were no longer used for residential purposes, some of which corresponds with well-documented region-wide drought. Past research has demonstrated that some population levels could have been maintained in these regions, yet regional scale depopulation occurred. We look at the degree to which the network level property of embeddedness, along with population size, can help to explain why some regions were depopulated and others were not. SNA can help archaeologists examine why emigration occurred in some areas following an environmental crisis while other areas continued to be inhabited and even received migrants. Moreover, we modify SNA techniques to take full advantage of the time depth and spatial and demographic variability of our archaeological data set. The results of this study should be of interest to those who seek to understand human responses to past, present, and future worldwide catastrophes since it is now widely recognized that responses to major human disasters, such as hurricanes, were “likely to be shaped by pre-existing or new social networks” (as reported by Suter et al. (Research and Policy Review 28:1–10, 2009)). Show less
The main subject of this thesis is pelvic pain in women in secondary and/or tertiary medical care. Studies aim to examine: 1. The clinical course of acute abdominal pain and risks of pain... Show moreThe main subject of this thesis is pelvic pain in women in secondary and/or tertiary medical care. Studies aim to examine: 1. The clinical course of acute abdominal pain and risks of pain persistence. 2. The clinical course of chronic pelvic pain (CPP) and predictors of recovery. 3. The moderating and /or mediating factors of sexual functioning. 4. The reliability of videotaped compared to real-time laparoscopic findings. Results show that pain persisted in 30% of women after an acute episode of abdominal pain. A low education level and an abuse history at a younger age were risks for chronicity. Recovery from pain was observed in 20% to 25% of women with CPP. Only a decrease in catastrophizing pain was associated with an improvement in pain and adjustment. Women with CPP reported more sexual problems than pain free controls. Anxiety and depression moderated sexual problems, while sexual abuse was a non-specific predictor. Finally, the evaluations of videotaped laparoscopies to score endometriosis were reliable, apart from ovarian lesions. In case of adhesions such evaluations were inconsistent. Main conclusion: CPP in women has to be considered as a chronic pain condition in general. A model to assess women with CPP and facilitate pain management is suggested. Show less
Huidig beleid schrijft voor dat voor de bloedtransfusie plaatsvindt, het serum van de patient getest wordt op irreguliere anti-stoffen van rode bloedcellen. In dit boek onderzoekt Henk Schonewille... Show moreHuidig beleid schrijft voor dat voor de bloedtransfusie plaatsvindt, het serum van de patient getest wordt op irreguliere anti-stoffen van rode bloedcellen. In dit boek onderzoekt Henk Schonewille of dit beleid moet veranderen om bloedtransfusie veiliger te maken. Current pre-transfusion policy requires the patient's serum to be tested for the presence of irregular red blood cell antibodies. In case of an alloantibody, red blood cells lacking the corresponding antigen are transfused after an antoglobulin crossmatch. The aim of the study in this thesis is primarily to investigate whether this policy should change to improve transfusion safety Show less
