To comprehend texts readers build mental representations. To establish coherence and protect these representations against inaccuracies readers routinely monitor and validate textual information... Show moreTo comprehend texts readers build mental representations. To establish coherence and protect these representations against inaccuracies readers routinely monitor and validate textual information against two main informational sources –what they just read (the text itself) and what they know (their background knowledge). This dissertation focuses on validation processes in the context of reading comprehension. Texts today vary in accuracy and trustworthiness. To better understand how readers validate (written) materials against various sources of information, the experimental studies in this dissertation employed different research methods to examine the (neuro)cognitive architecture of the processes involved in validating against prior text (i.e., text-based validation) and validating against background knowledge (i.e., knowledge-based validation) and how these processes affect readers;’ memory for text information.Results illustrate that readers validate incoming information against these two sources in dissociable, (partially) interactive, text-based and knowledge-based validation processes. Moreover, these processes seem to protect readers’ memory against inaccuracies or incongruencies. These observations deepen our understanding of validation processes, provide starting points for investigations of people’s susceptibility to false information and how inaccurate knowledge can be revised and provide insight into the complex interplay between recently acquired knowledge from the text itself and background knowledge in constructing meaning from language. Show less
Exploring novel environments enhances learning in animals. Due to differing traditions, research into the effects of spatial novelty on learning in humans is scarce. Recent developments of... Show moreExploring novel environments enhances learning in animals. Due to differing traditions, research into the effects of spatial novelty on learning in humans is scarce. Recent developments of affordable and fMRI-compatible virtual reality (VR) and mobile EEG systems can help bridge the gap between the two literatures. One promising study showed that spatial novelty also promotes learning in humans. It still remains largely unknown, however, which aspect of novelty underlies the beneficial effect on memory, as novelty, expectations, and volition are often confounded in animal studies. In humans, these factors can be experimentally manipulated, but such studies are currently lacking. Future studies in humans could combine pharmacological interventions, neuroimaging and VR or use mobile EEG to help elucidate whether the plasticity enhancing mechanisms observed in animals, also exist in humans. When the aspects of exploring a novel environment underlying beneficial memory effects have been identified, effective novelty-exposure interventions could be designed to improve learning and counteract age-related memory decline. Show less
This dissertation addresses the question of what it means to remake everyday life in the shadow of disaster. Focusing on the city of Banda Aceh, Indonesia, in the years after the devastating Indian... Show moreThis dissertation addresses the question of what it means to remake everyday life in the shadow of disaster. Focusing on the city of Banda Aceh, Indonesia, in the years after the devastating Indian Ocean tsunami of December 26, 2004, it explores how tsunami survivors have been remaking the everyday ever since that moment. Based on ethnographic research in the post-disaster years, the five chapters of this dissertation discuss various dimensions of the remaking of everyday life that were important to the tsunami survivors, including the reconstruction of houses, interactions between survivors, international organizations and the state, the narrative experiences of the tsunami, the process of grieving and its entanglement with Islam, the creation of collective memory and forgetfulness in urban space, and ideas about the future that build on notions of moral and socio-economic improvement. In these chapters the concept of subjectivity is used to show how individuals creatively shape their lives in the context of tremendous social, economic, and political changes. The dissertation concludes that the anthropology of disaster, that has up to now predominantly focused on post-disaster social change and continuity and on structural historical patterns of vulnerability and resilience, can be enriched by ethnographic studies of subjectivity. Show less
The main goal of the present thesis was to study the effects of stress and stress hormones on the retrieval of emotional memories in healthy humans. In addition, we were interested in the effects... Show moreThe main goal of the present thesis was to study the effects of stress and stress hormones on the retrieval of emotional memories in healthy humans. In addition, we were interested in the effects of stress hormones on post-retrieval processes like reconsolidation. That is, are there only acute and temporary effects of stress hormones on memory retrieval, or are there also long-term effects? Studying effects of stress hormones can be done in two ways; either by (experimentally) inducing stress in humans, or by exogenously administering doses of stress hormones. In the present thesis both ways were used. Furthermore, when investigating emotional memories, we can make use of memories that are created in a laboratory setting or those that derive from real life experiences, i.e. autobiographical memories. Again, both methods were investigated. We found acute stress and a single cortisol administration to have direct and long-term impairing effects on memory for neutral and emotional information that was learned and reactivated in a controlled laboratory situation. Future studies should shed more light on the generalizability of these findings to real life settings and clinical practice. Show less
Early dementias are difficult to distinguish from normal age-related memory decline. In the preclinical stages of Alzheimer’s disease and Huntington’s disease, brain functions are already changing... Show moreEarly dementias are difficult to distinguish from normal age-related memory decline. In the preclinical stages of Alzheimer’s disease and Huntington’s disease, brain functions are already changing, but this is not directly visible from the outside. Many research is aimed at discovering early disease markers. However, research using EEG registration during conventional eyes closed conditions revealed little additional information. The yield of EEG research can be improved by probing the weakest spot, which, in case of dementia, is memory. Karin van der Hiele introduced memory tests during EEG registration and found that early abnormalities in brain functioning can then be observed in Alzheimer’s disease and Huntington’s disease. An interesting finding came to light: the EEG in dementia displays a lot of muscle activity which is normally filtered out. However, the researchers decided not to throw this activity away but to measure it. Interestingly, they found that the amount of muscle activity was related to cognition and to the number of depressive complaints. It may pay to keep an open mind regarding the nature of the parameter to be measured. Show less
