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A pervasive real-world memory task is remembering to carry out intended activities at appropriate moments in the future, such as remembering to call one’s mother after returning from work or to hand a message to a colleague when seeing him in the office on the next morning. Such types of tasks are termed prospective memory (PM) tasks (Einstein & McDaniel, 1996). PM has been identified as one of the most frequent everyday memory challenges (e.g., Maylor, 1990), particularly in old age (McDaniel, Einstein, & Rendell, 2008) and an intact PM is considered to be crucial for the maintenance of independent living (Kliegel & Martin, 2003). Therefore, many researchers have focused on the exploration of possible age differences in PM. While age-related deficits were found in standard lab-based PM tasks, age-related benefits occured in naturalistic tasks that are carried out in participants’ everyday lives. This surprising pattern has been called the age-PM-paradox (Rendell & Craik, 2000). It has been supported by a meta-analysis comparing PM age effects found in studies that focused either on lab-based or on naturalistic PM tasks (Henry, MacLeod, Phillips, & Crawford, 2004). However, the mechanisms which are critical in determining the direction of age effects remain poorly delineated. Thus, the overall aim of the research programme presented in the present thesis was to investigate the age-PM-paradox as well as potential cognitive, motivational and emotional mechanisms and processes associated with age-related PM performance. For that purpose, three experimental studies were conducted testing adult age effects in different PM task settings with different task material. Furthermore, several possible underlying mechanisms suggested by the literature on age effects in PM were measured and/ or varied experimentally. The first aim of Study 1 was to cross-validate the age-PM-paradox within a single sample. The second aim was to empirically explore the relative importance of four recently proposed factors (motivation, metacognitive awareness, activity absorption, and control over the task) that may be associated with the direction of age effects inside and outside of the laboratory. For that purpose, 20 young and 20 older adults performed a lab-based and a naturalistic PM task, which were similar in structure and demand. The level of control was experimentally manipulated in both task settings. The remaining possibly influencing factors (motivation, metacognitive awareness, and activity absorption) were assessed via questionnaires in the laboratory and with a daily diary in the field. First, analysing mean level age differences, the paradox was confirmed. Second, exploring possible correlates of the paradox revealed that the level of daily activity absorption (i.e., everyday stress) was the most important mechanism in naturalistic PM performance. Further, high motivation and good metacognitive awareness were associated with age benefits in PM performance in the naturalistic task, while high ongoing activity absorption and low control over the PM cue were related to deficits in lab-based tasks. Thus, Study 1 confirmed the age-PM-paradox within one sample and with carefully matched lab-based and naturalistic tasks. In addition, the results indicate that the relative importance of the suggested factors may vary as a function of setting. While cognitive factors were most influential in the laboratory, motivational and knowledge-based factors were associated with high PM performance in the naturalistic task. The strong association between PM performance in the field and everyday stress highlights the need for future studies exploring the mechanisms underlying this effect. Results from Study 1 suggest that cognitive resources are most influential for PM age effects in the laboratory. Yet, it is not clear, which specific cognitive resources are needed for successful PM performance and if these processes differ between young and older adults. Thus, Study 2 explored the role of executive functions (i.e. shifting, updating and inhibition) as possible developmental mechanisms associated with PM age effects. 170 young and 110 older adults performed a battery of cognitive tests including measures of PM, shifting, updating, inhibition, working memory and speed. A comprehensive set of statistical approaches (e.g. median analyses, structural equation modelling) was used to analyze the possible cognitive correlates in predicting PM performance. First, age effects were confirmed in PM and also obtained in measures of executive control. Moreover, the facets of executive control differently predicted PM performance. Specifically, shifting was the strongest predictor of PM performance in young and older adults as well as for explaining age differences in PM. Thus, Study 2 clarified the role of different facets of controlled attention in age effects in PM and bears important conceptual implications: The results suggest that executive functions are important developmental mechanisms of PM across adulthood beyond working memory and speed. Specifically, shifting appeared to be an essential aspect of cognitive control involved in age-related PM performance. Moreover, examining PM as a latent construct confirmed the convergent and discriminant validity of PM. This demonstrates PM as a separate cognitive construct and suggests that PM is related to, but not identical with, executive control. Study 3 was set out to explore if the amount of cognitive resources needed to successfully perform a PM task in the laboratory can be influenced by the emotionality of the task material. First studies suggested that emotional task material may enhance PM performance in young and older adults by heightening the salience of the task and thereby reducing the need for controlled attention. However, the extent and mechanisms of this effect are still under debate. Therefore, Study 3 explored possible differential effects of PM target cue valence on PM age effects. For that purpose, 45 young and 41 older adults performed a PM task in which emotional valence of the PM cue was manipulated (positive, negative, neutral). Results revealed an interaction indicating that age differences were smaller in both emotional valence conditions compared to the neutral condition. This finding supports an emotionally enhanced memory effect in PM, but only for the older adults as PM performance in young adults was not affected by cue valence. From a conceptual perspective, the results from Study 3 may also contribute to the explanation of the age-PM-paradox, as they suggest that the neutral material usually applied in lab-based studies might overestimate PM age effects. In summary, the present thesis makes an important contribution to the ongoing conceptual debate concerning adult age effects in PM performance assessed in the laboratory versus participants’ everyday lives. Results strongly suggest that mostly different variables may be crucial for understanding PM age deficits in the laboratory and age benefits in naturalistic PM tasks. Successful PM performance in the laboratory seems to require high levels of cognitive resources. The present results suggest that shifting ability is especially relevant in this respect. On a task level the emotionality of the material seems to influence the required amount of cognitive resources as it reduced PM age effects. Everyday stress seems to be particularly important for successful PM performance in the field. Thus, possible future studies should specify the relation between stress and PM as outlined in the general discussion.

Die Informationssuche und –integration konnten bei gedächtnisbasierten Multi-Attribut-Entscheidungen bislang nicht untersucht werden. Die vorliegende Arbeit beschäftigt sich mit der Entwicklung eines neuen prozessbasierten Verfahrens, das auf einer Analyse von Blickbewegungen beruht. Das Verfahren wurde in einer experimentellen Untersuchung erprobt. In einer vorangestellten Lernphase eigneten sich die Versuchsteilnehmer Eigenschaftsausprägungen (Cue-Ausprägungen) von sechs verschiedenen Alternativen an. Die Eigenschaftsausprägungen waren in Textform in rechteckigen Kästen um eine bildliche Darstellung einer Alternative angeordnet. In der darauf folgenden Entscheidungsphase führten die Teilnehmer gedächtnisbasierte Entscheidungen zwischen jeweils zwei der Alternativen durch. Die eine Hälfte der Versuchsteilnehmer bekam die nichtkompensatorische Take the best (TTB) Heuristik instruiert, die andere Hälfte die kompensatorische Dawes Rule (DR). Während der Entscheidungsphase wurden die Blickbewegungen der Versuchsteilnehmer aufgezeichnet. Es wurde angenommen, dass sich die Blickbewegungen zwischen den zwei Gruppen instruierter und nach ihrem Entscheidungsverhalten klassifizierter Versuchsteilnehmer hinsichtlich der strategieinduzierten Suchmuster unterscheiden würden. Diese Annahme beruht auf Befunden, die zeigen, dass Versuchsteilnehmer beim Informationsabruf an die Orte zurückblicken, an denen sie zuvor Informationen aufgenommen haben, selbst wenn diese Informationen dort nicht mehr stehen. Verwender der TTB Heuristik zeigten mehr Blickwechsel zwischen den Alternativen, je später der erste Cue differenzierte, und sie verweilten kürzer in einer Alternative, bevor sie den Blick auf die andere Alternative richteten. Bei DR Verwendern fanden sich erwartungsgemäß keine Unterschiede in den Blickwechselhäufigkeiten, je später der erste Cue differenzierte, und sie verweilten länger innerhalb einer Alternative vor einem Blickwechsel. Die Ergebnisse stützen die Idee, dass Blickbewegungen wertvolle Informationen über die kognitiven Prozesse während der Gedächtnissuche liefern können. Das Potenzial der Blickbewegungsmessung als Prozessmaß zur Untersuchung gedächtnisbasierter Entscheidungen wird diskutiert. / The common methods for studying heuristics in memory-based multi-attribute decisions provide outcome and response measures but do not directly observe information search. Hence, foregoing cognitive processes cannot be explored. In the presented experiment a novel process-tracing method is introduced that uses eye-tracking to study memory-based decisions. It is based on the so-called ‘looking at nothing’ effect that assumes that people fixate on blank locations if a relevant visual stimulus previously occupied that location. Therefore, participants learned cue information of decision alternatives in spatial frames. In the decision phase they were presented with emptied displays of two alternatives and performed binary choices between them. Participants were instructed to decide either according to a lexicographic or a compensatory strategy. Fixation patterns on former cue locations and reaction times mirrored memory search and cue processing as assumed for the tested strategies.

From the simple act of picking up a glass of water while talking to someone at a party, to remembering to swing by the bike shop to pick up an inner tube while riding through traffic on our way home from the office, intentions guide and alter our behavior—often while we are busily engaged in other ongoing tasks. Particularly, performing delayed intentions, like stopping at the bike shop on our way home, relies on a set of cognitive processes summarized as prospective memory (PM) that enable us to postpone intended actions until a later point in time (time-based PM) or until specific reminders or PM cues signal the appropriate opportunity to retrieve and perform an intended action (event-based PM). Interestingly, over the past decades a growing number of studies showed that successfully completing an event-based intention does not necessarily lead to its immediate deactivation. Instead, no-longer-relevant PM cues can incur so-called aftereffects that impair task performance and sometimes even trigger erroneous repetitions of the intended action (i.e., commission errors). Although in our everyday lifes we frequently rely on both PM and intention deactivation, still relatively little is known about how our cognitive system actually manages to deactivate completed intentions, under which conditions this may fail, and how well PM and intention deactivation function under extreme conditions, like acute stress. In order to answer these questions, I first conducted a comprehensive review of the published literature on aftereffects of completed intentions. Here, I found that although intentions can incur aftereffects in terms of commission errors and performance costs that most likely result from continued intention retrieval, they generally seem to be deactivated or even inhibited at some point. Most importantly, this deactivation process does not operate like a light switch but dynamically moves along a continuum from complete reactivation to complete deactivation of intentions, and is substantially modulated by factors that also affect retrieval of intentions prior to their completion. Specifically, intention deactivation is most likely to fail when we remain within the same context in which we originally completed the intention and encounter no-longer-relevant PM cues that are extremely salient and were strongly linked to the intended action. Subsequently, in Study 1 I directly tested a dual-mechanisms account of aftereffects of completed intentions. Building on findings of impaired intention deactivation in older adults who often show deficits in cognitive-control abilities, this account posits that aftereffects and commission errors in particular stem from a failure to exert cognitive control when no-longer-relevant PM cues trigger retrieval of an intention. Accordingly, intention deactivation should hinge on the availability of cognitive-control resources at the moment we encounter no-longer-relevant PM cues. In order to test this, I assessed aftereffects of completed intentions in younger and older adults while manipulating transient demands on information processing during encounters of no-longer-relevant PM cues on a trial-by-trial basis. In Experiment 1, nominally more older adults than younger adults made a commission error. Additionally, medium demands on cognitive control substantially reduced aftereffects compared to low and high demands (i.e., u-shaped relation). In Experiment 2, which extended this manipulation but only tested younger adults, however, this control-demand effect did not replicate. Instead, aftereffects occurred regardless of cognitive-control demands. The lack of a consistent control-demand effect on aftereffects across two experiments, suggested that cognitive control either only plays a minor role for the occurrence of aftereffects or that, more likely, intention deactivation hinges on other specific cognitive-control abilities, like response inhibition. In two subsequent studies, I extended this research and tested the effects of acute stress—a potent modulator of cognitive-control functioning—on PM and intention deactivation. Previous studies showed that, under moderate demands, acute stress had no effect on PM-cue detection, intention deactivation or performance costs that presumably arise from monitoring for PM cues. Importantly, however, based on these studies it remained unclear if acute stress affects PM and intention deactivation under high demands, as has been observed, for instance, with working-memory performance. To test such a potential demand-dependence of acute stress effects on PM, I first assessed the effects of psychosocial stress induction with the Trier Social Stress Test on PM and intention deactivation when detecting PM cues and intention deactivation were either low or high demanding (Study 2). Building on this work, I then tested the effects of combined physiological and psychosocial stress induction with the Maastricht Acute Stress Test on PM and the ability to track one’s own performance (i.e., output monitoring), when PM-cue detection was difficult and ongoing tasks additionally posed either low or high demands on working memory (Study 3). Despite successful stress induction (e.g., increased levels of salivary cortisol and impaired subjective mood), both studies showed that PM-cue detection and intention retrieval were not affected by acute stress under any of these conditions. Study 2 revealed a tendency for a higher risk of making commission errors under stress when no-longer-relevant PM cues were salient and difficult to ignore. Study 3 additionally showed that acute stress had no effect on output monitoring. Most importantly, however, across the different PM tasks and stress-induction protocols in these studies, acute stress substantially reduced performance costs from monitoring for PM cues, but did so only when PM-cue detection was difficult. This effect suggested that, depending on task demands, acute stress might shift retrieval processes in PM away from costly monitoring-based retrieval towards a more economic spontaneous retrieval of intended actions. In summary, the present thesis suggests that the processes underlying prospective remembering and intention deactivation are tightly woven together and are only selectively affected by cognitive-control availability and effects of acute stress. With this, it contributed substantially to our understanding of these essential cognitive capacities and their reliability. My research showed that PM is remarkably resilient against effects of acute stress experiences when remembering intended actions is supported by external reminders. Acute stress may actually make monitoring for such reminders more efficient when they are hard to detect. Additionally, it showed that, in most circumstances, we seem to be able to successfully and quickly deactivate intentions once they are completed. It is only under some conditions that intention deactivation may be slow, sporadic or fail, which can lead to continued retrieval of completed intentions. While this seems not to be affected by transient demands on information processing during encounters of no-longer-relevant PM cues, intention deactivation might become difficult for older adults and stressed individuals when no-longer-relevant reminders of intentions easily trigger the associated action and are hard to ignore.

In der heutigen Zeit bilden Netzwerke, auf technologischer sowie sozialer Ebene, die zentralen Systeme in der Informationsverarbeitung. Graphen stellen mit ihren mathematischen Eigenschaften eine geeignete Art der Beschreibung von Netzwerken dar. Seit 1741, beginnend mit Eulers Königsberger Brückenproblem (Euler 1741), werden Graphen für die Visualisierung thematisiert. Mit Beginn der Netzwerktechnik Mitte des 20. Jahrhunderts und der Entstehung digitaler sowie sozialer Netzwerke wächst das Interesse an der Visualisierung von Graphen. Dies setzt sich zu Beginn des 21. Jahrhunderts mit dem Aufbau von Firmennetzwerken und deren steigender Komplexität fort. Verschiedene Bereiche wie Psychologie, Mathematik, Kunst, Mensch-Maschine-Systemtechnik und Mediengestaltung beeinflussen die Ausprägung der Visualisierung von Graphen. Insbesondere psychologische Aspekte der visuellen Wahrnehmung und der kognitiven Leistung bilden die Grundlage zur Gestaltung von Graphen. Netzwerke beinhalten einen hohen Informationsgrad für den Rezipienten. Am Beispiel komplexer Firmennetzwerke stellt sich die Herausforderung nach einer effizienten und individuellen Exploration. Aktuelle Lösungen in Form von Tabellen und Datenbankabfragesprachen erzeugen eine hohe kognitive Last des Nutzers. Die Darstellung von Netzwerken in Graphen unterstützt den Nutzer in der Erfassung des Kontexts. Aktuelle Visualisierungskonzepte für Graphen bieten nur geringe Möglichkeiten der individuellen Exploration. Dies resultiert in einem „Lost-in-Context“-Effekt und einer erhöhten kognitiven Last. Das Visualisierungs- und Interaktionskonzept dieser Arbeit ermöglicht die Reduktion des „Lost-in-Context“-Effekts sowie der kognitiven Last. Dieser Forschungsansatz der Arbeit lässt sich dazu in drei Betrachtungsbereiche unterteilen: das Gedächtnismodell zur visuellen Kognition, das globale Strukturmittel und die lokalen Strukturmittel der graphenbasierten Exploration. Im Bereich der visuellen Kognition wird als Grundlage das Gedächtnismodell von Kosslyn diskutiert und adaptiert. Diese Adaption für die graphenbasierte Exploration zeigt die Verwendung von mentalen Karten des Nutzers. Dies basiert auf der Identifikation von semantischen und numerischen Werten der wahrgenommenen Objekte. Das globale Strukturmittel „Multi-Level-of-Detail“-Konzept basiert auf der Abbildung semantischer und numerischer Eigenschaften von wahrgenommenen Objekten auf eine mentale Karte. Das Gedächtnismodell von Kosslyn wird für die graphenbasierte Exploration angepasst und stellt die Grundlage für diese Abbildung dar. Das globale Strukturmittel ermöglicht dem Nutzer, parallel mehrere Detailstufen in der Graphvisualisierung zu erzeugen und individuell zu manipulieren. Dies reduziert die kognitive Last während der graphenbasierten Exploration. Die Einführung des globalen Strukturmittels fordert die Betrachtung lokaler Strukturmittel zur visuellen Wahrnehmung und Gestaltung des Graphen. Im Bereich der lokalen Strukturmittel werden die verschiedenen graphischen und interaktiven Mittel zur graphenbasierten Exploration diskutiert. Vor dem Hintergrund des aufgestellten Gedächtnismodells sowie den Grundlagen der Gestaltgesetze wird ein Baukasten visueller Elemente zur Gestaltung von Graphen betrachtet. Dieser wird durch die Diskussion der Eigenschaften der Graphobjekte, zum Beispiel: Position, Größe, Form, Clustern und Bündeln, beeinflusst. In einer prototypischen Umsetzung des Konzepts wird, im Vergleich zu Tabellen und Datenbankabfragesprachen, am Beispiel eines komplexen Firmennetzwerks die Reduktion der kognitiven Last gezeigt. Die Evaluation der kognitiven Last erfolgt mittels des NASA-TLX. In einem „Within-Subject“ Experiment werden Experten zu dem Konzept befragt. Dieses zeigt, dass im Vergleich zu aktuellen Graphdarstellungen eine Reduktion des „Lost-in-Context“-Effekts eintritt. Zusätzlich konnte gezeigt werden, dass nicht alle gestalterischen Mittel der lokalen Strukturmittel, im Vergleich zu aktuellen Lösungen und Konzepten, eine Verbesserung brachten. Die zentralen Aspekte des eingeführten Konzepts zeigen die Verwendung von mentalen Karten während der graphenbasierten Exploration komplexer Netzwerke.

A pervasive real-world memory task is remembering to carry out intended activities at appropriate moments in the future, such as remembering to call one’s mother after returning from work or to hand a message to a colleague when seeing him in the office on the next morning. Such types of tasks are termed prospective memory (PM) tasks (Einstein & McDaniel, 1996). PM has been identified as one of the most frequent everyday memory challenges (e.g., Maylor, 1990), particularly in old age (McDaniel, Einstein, & Rendell, 2008) and an intact PM is considered to be crucial for the maintenance of independent living (Kliegel & Martin, 2003). Therefore, many researchers have focused on the exploration of possible age differences in PM. While age-related deficits were found in standard lab-based PM tasks, age-related benefits occured in naturalistic tasks that are carried out in participants’ everyday lives. This surprising pattern has been called the age-PM-paradox (Rendell & Craik, 2000). It has been supported by a meta-analysis comparing PM age effects found in studies that focused either on lab-based or on naturalistic PM tasks (Henry, MacLeod, Phillips, & Crawford, 2004). However, the mechanisms which are critical in determining the direction of age effects remain poorly delineated. Thus, the overall aim of the research programme presented in the present thesis was to investigate the age-PM-paradox as well as potential cognitive, motivational and emotional mechanisms and processes associated with age-related PM performance. For that purpose, three experimental studies were conducted testing adult age effects in different PM task settings with different task material. Furthermore, several possible underlying mechanisms suggested by the literature on age effects in PM were measured and/ or varied experimentally. The first aim of Study 1 was to cross-validate the age-PM-paradox within a single sample. The second aim was to empirically explore the relative importance of four recently proposed factors (motivation, metacognitive awareness, activity absorption, and control over the task) that may be associated with the direction of age effects inside and outside of the laboratory. For that purpose, 20 young and 20 older adults performed a lab-based and a naturalistic PM task, which were similar in structure and demand. The level of control was experimentally manipulated in both task settings. The remaining possibly influencing factors (motivation, metacognitive awareness, and activity absorption) were assessed via questionnaires in the laboratory and with a daily diary in the field. First, analysing mean level age differences, the paradox was confirmed. Second, exploring possible correlates of the paradox revealed that the level of daily activity absorption (i.e., everyday stress) was the most important mechanism in naturalistic PM performance. Further, high motivation and good metacognitive awareness were associated with age benefits in PM performance in the naturalistic task, while high ongoing activity absorption and low control over the PM cue were related to deficits in lab-based tasks. Thus, Study 1 confirmed the age-PM-paradox within one sample and with carefully matched lab-based and naturalistic tasks. In addition, the results indicate that the relative importance of the suggested factors may vary as a function of setting. While cognitive factors were most influential in the laboratory, motivational and knowledge-based factors were associated with high PM performance in the naturalistic task. The strong association between PM performance in the field and everyday stress highlights the need for future studies exploring the mechanisms underlying this effect. Results from Study 1 suggest that cognitive resources are most influential for PM age effects in the laboratory. Yet, it is not clear, which specific cognitive resources are needed for successful PM performance and if these processes differ between young and older adults. Thus, Study 2 explored the role of executive functions (i.e. shifting, updating and inhibition) as possible developmental mechanisms associated with PM age effects. 170 young and 110 older adults performed a battery of cognitive tests including measures of PM, shifting, updating, inhibition, working memory and speed. A comprehensive set of statistical approaches (e.g. median analyses, structural equation modelling) was used to analyze the possible cognitive correlates in predicting PM performance. First, age effects were confirmed in PM and also obtained in measures of executive control. Moreover, the facets of executive control differently predicted PM performance. Specifically, shifting was the strongest predictor of PM performance in young and older adults as well as for explaining age differences in PM. Thus, Study 2 clarified the role of different facets of controlled attention in age effects in PM and bears important conceptual implications: The results suggest that executive functions are important developmental mechanisms of PM across adulthood beyond working memory and speed. Specifically, shifting appeared to be an essential aspect of cognitive control involved in age-related PM performance. Moreover, examining PM as a latent construct confirmed the convergent and discriminant validity of PM. This demonstrates PM as a separate cognitive construct and suggests that PM is related to, but not identical with, executive control. Study 3 was set out to explore if the amount of cognitive resources needed to successfully perform a PM task in the laboratory can be influenced by the emotionality of the task material. First studies suggested that emotional task material may enhance PM performance in young and older adults by heightening the salience of the task and thereby reducing the need for controlled attention. However, the extent and mechanisms of this effect are still under debate. Therefore, Study 3 explored possible differential effects of PM target cue valence on PM age effects. For that purpose, 45 young and 41 older adults performed a PM task in which emotional valence of the PM cue was manipulated (positive, negative, neutral). Results revealed an interaction indicating that age differences were smaller in both emotional valence conditions compared to the neutral condition. This finding supports an emotionally enhanced memory effect in PM, but only for the older adults as PM performance in young adults was not affected by cue valence. From a conceptual perspective, the results from Study 3 may also contribute to the explanation of the age-PM-paradox, as they suggest that the neutral material usually applied in lab-based studies might overestimate PM age effects. In summary, the present thesis makes an important contribution to the ongoing conceptual debate concerning adult age effects in PM performance assessed in the laboratory versus participants’ everyday lives. Results strongly suggest that mostly different variables may be crucial for understanding PM age deficits in the laboratory and age benefits in naturalistic PM tasks. Successful PM performance in the laboratory seems to require high levels of cognitive resources. The present results suggest that shifting ability is especially relevant in this respect. On a task level the emotionality of the material seems to influence the required amount of cognitive resources as it reduced PM age effects. Everyday stress seems to be particularly important for successful PM performance in the field. Thus, possible future studies should specify the relation between stress and PM as outlined in the general discussion.

Regular use of illegal drugs is suspected to cause cognitive impairments. Two substances have received heightened attention: 3,4-methylenedioxymethamphetamine (MDMA or ‘ecstasy’) and δ-9-tetrahydrocannabinol (THC or ‘cannabis’). Preclinical evidence, as well as human studies examining regular ecstasy consumers, indicated that ecstasy use may have negative effects on learning, verbal memory and complex attentional functions. Cannabis has also been linked to symptoms of inattention and deficits in learning and memory. Most of the published studies in this field of research recruited participants by means of newspaper advertisements or by using word-of-mouth strategies. Because participants were usually aware that their drug use was critical to the research design, this awareness may have caused selection bias or created expectation effects. Focussing on attention and memory, this study aimed to assess cognitive functioning in a community-based representative sample that was derived from a large-scale epidemiological study. Available data concerning drug use history allowed sampling of subjects with varying degrees of lifetime drug experiences. Cognitive functioning was examined in 284 young participants, between 22 and 34 years. In general, their lifetime drug experience was moderate. Participants completed a neuropsychological test battery, including measures for verbal learning, memory and various attentional functions. Linear regression analysis was performed to investigate the relationship between cognitive functioning and lifetime experience of drug use. Ecstasy and cannabis use were significantly related to poorer episodic memory function in a dose-related manner. For attentional measures, decrements of small effect sizes were found. Error measures in tonic and phasic alertness tasks, selective attention task and vigilance showed small but significant effects, suggesting a stronger tendency to experience lapses of attention. No indication for differences in reaction time was found. The results are consistent with decrements of memory and attentional performance described in previous studies. These effects are relatively small; however, it must be kept in mind that this study focussed on assessing young adults with moderate drug use from a population-based study.

Die vorliegende Arbeit ist eine Staatsexamensarbeit im Fach Geschichte. Sie beschäftigt sich mit der Rezeption des Bombenangriffes auf Dresden am 13./14. Febraur 1945 in der Geschichtspolitik der DDR. Die Arbeit untersucht anhand der Vor- und Nachberichterstattung der lokalen Zeitungen, der politisch inszenierten Gedenkveranstaltungen und -rituale sowie der entstandenen Erinnerungsorte die Funktion und den Stellenwert dieses Gedenktages in der DDR.