Disturbed memory and amnesia related to intensive care

Patients, when admitted to an intensive care unit (ICU), have one thing in common: their illness is life-threatening. Patients may remain on ICU in a critical condition, needing support with their breathing, circulation, and/or kidneys for varying lengths of time, from days to weeks. During that time the patients will receive sedative and analgesic drugs to ensure compliance with artificial ventilation. Patients recovering from critical illness frequently have little or no recall of their period in ICU, or remember nightmare, hallucinations, or paranoid delusions. The nature, extent and reason for these difficulties, have been under-reported and consequently our purpose was to conduct a review of memory problems experienced by ICU patients. A systematic literature review of computer databases (Medline, PsycLit, and CINAHL) identified 25 relevant papers. In addition, other relevant articles were obtained, citation lists and associated articles retrieved. Due to lack of research on processes underlying memory problems in ICU patients all articles that introduced an insight into possible mechanisms were included in the review. There seem to be two possible processes contributing to memory problems in ICU patients. First the illness and treatment may have a general dampening effect on memory. Delirium and sleep disturbance are both common in ICU patients. Delirium can result in a profound amnesia for the period of confusion. Sleep deprivation exacerbates the confusional state. Slow wave sleep is important for the consolidation of episodic memories. Treatment administered to patients in ICU can have effects on memory. Opiates, benzodiazepines, sedative drugs such as propofol, adrenaline, and corticosteroids can all influence memory. In addition, the withdrawal of drugs, such as benzodiazepines, can cause profound withdrawal reactions, which may contribute to delirium. Second, we hypothesise that there is a process that affects memory negatively for external events but enhances memory for internal events. The physical constraints and social isolation experienced by ICU patients and the life-threatening nature of the illness may increase the experience of hypnagogic hallucinations. Attentional shift during hypnagogic images from external stimuli to internally generated images would explain why ICU patients have such poor recall of external ICU events, but can clearly remember hallucinations and nightmares. Patients describe these memories as being very vivid and this is explored in terms of flashbulb memory formation. The absence of memories for real events on ICU can result in ICU patients remembering paranoid delusions of staff trying to kill them, with little information to reject these vivid memories as unreal. This has implications for patients' future psychological health.     

The Challenges of Large-Scale,Web-Based Language Datasets: Word Length and Predictability Revisited

Language research has come to rely heavily on large-scale, web-based datasets. These datasets can present significant methodological challenges, requiring researchers to make a number of decisions about how they are collected, represented, and analyzed. These decisions often concern long-standing challenges in corpus-based language research, including determining what counts as a word, deciding which words should be analyzed, and matching sets of words across languages. We illustrate these challenges by revisiting “Word lengths are optimized for efficient communication” (Piantadosi, Tily, & Gibson, 2011), which found that word lengths in 11 languages are more strongly correlated with their average predictability (or average information content) than their frequency. Using what we argue to be best practices for large-scale corpus analyses, we find significantly attenuated support for this result and demonstrate that a stronger relationship obtains between word frequency and length for a majority of the languages in the sample. We consider the implications of the results for language research more broadly and provide several recommendations to researchers regarding best practices.     

Sensitivity to Shared Information in Social Learning

Social learning has been shown to be an evolutionarily adaptive strategy, but it can be implemented via many different cognitive mechanisms. The adaptive advantage of social learning depends crucially on the ability of each learner to obtain relevant and accurate information from informants. The source of informants’ knowledge is a particularly important cue for evaluating advice from multiple informants; if the informants share the source of their information or have obtained their information from each other, then their testimony is statistically dependent and may be less reliable than testimony from informants who do not share information. In this study, we use a Bayesian model to determine how rational learners should incorporate the effects of shared information when learning from other people, conducting three experiments that examine whether human learners behave similarly. We find that people are sensitive to a number of different patterns of dependency, supporting the use of a sophisticated strategy for social learning that goes beyond copying the majority, and broadening the situations in which social learning is likely to be an adaptive strategy.     

Faster Teaching via POMDP Planning

Human and automated tutors attempt to choose pedagogical activities that will maximize student learning, informed by their estimates of the student's current knowledge. There has been substantial research on tracking and modeling student learning, but significantly less attention on how to plan teaching actions and how the assumed student model impacts the resulting plans. We frame the problem of optimally selecting teaching actions using a decision‐theoretic approach and show how to formulate teaching as a partially observable Markov decision process planning problem. This framework makes it possible to explore how different assumptions about student learning and behavior should affect the selection of teaching actions. We consider how to apply this framework to concept learning problems, and we present approximate methods for finding optimal teaching actions, given the large state and action spaces that arise in teaching. Through simulations and behavioral experiments, we explore the consequences of choosing teacher actions under different assumed student models. In two concept‐learning tasks, we show that this technique can accelerate learning relative to baseline performance.     

A Systematic Review of the Effectiveness of Acceptance and Commitment Therapy (ACT) for Body Image Dissatisfaction and Weight Self-Stigma in Adults

Body image dissatisfaction (BID) and weight self-stigma are prevalent and associated with physical and psychological ill-health. Acceptance and Commitment Therapy (ACT) is increasingly employed for both, yet little is known about its effectiveness. Searches of 12 databases identified six studies using online, face-to-face or self-help ACT interventions for BID or weight self-stigma, of varying duration and intensity. Their effectiveness and quality were evaluated. Two reported improved BID, three improved weight self-stigma, and one reported no impact on weight self-stigma. Methodological issues (small sample sizes, lack of allocation concealment, attention control and long-term follow up) impacted the validity of findings. Due to the small number of studies and poor study quality, the effectiveness of ACT for BID and weight self-stigma remains unclear. Nonetheless findings suggest psychological flexibility may facilitate reduction in BID and weight self-stigma and indicate that brief online as well as lengthy face-to-face delivery may be useful. Suggestions for further research are made.     

Online guidance, advice, and support for problem gamblers and concerned relatives and friends: an evaluation of the GamAid pilot service

The paper reports one of the first ever studies to evaluate the effectiveness of an online help and guidance service for problem gamblers. The evaluation utilised a mixed methods design in order to examine both primary and secondary data relating to the client experience. In addition, the researchers posed as problem gamblers in order to obtain first-hand experience of how the service works in practice. A total of 80 participants completed an online evaluation questionnaire, and secondary data were gathered from 413 distinct clients who contacted an advisor. It was concluded that the service appears to be one of the few genuinely international guidance and 'counselling' services available to problem gamblers. Gambling online was the most preferred form of gambling and gambling location of GamAid clients. The service also appears to be favoured by females more than any other comparable service. Overall, the vast majority of clients were very positive about their experience of using GamAid, although there were some minor technical difficulties. In light of the findings, the utility of using online guidance and therapeutic services is discussed.     

Can being scared cause tummy aches? Naive theories, ambiguous evidence, and preschoolers' causal inferences

Causal learning requires integrating constraints provided by domain-specific theories with domain-general statistical learning. In order to investigate the interaction between these factors, the authors presented preschoolers with stories pitting their existing theories against statistical evidence. Each child heard 2 stories in which 2 candidate causes co-occurred with an effect. Evidence was presented in the form: AB?E; CA?E; AD?E; and so forth. In 1 story, all variables came from the same domain; in the other, the recurring candidate cause, A, came from a different domain (A was a psychological cause of a biological effect). After receiving this statistical evidence, children were asked to identify the cause of the effect on a new trial. Consistent with the predictions of a Bayesian model, all children were more likely to identify A as the cause within domains than across domains. Whereas 3.5-year-olds learned only from the within-domain evidence, 4- and 5-year-olds learned from the cross-domain evidence and were able to transfer their new expectations about psychosomatic causality to a novel task.     

Acquisition, development, and maintenance of online poker playing in a student sample.

To date there has been very little empirical research into Internet gambling and none relating to the recent rise in popularity of online poker. Given that recent reports have claimed that students may be a vulnerable group, the aim of the current study was to establish basic information regarding Internet poker playing behavior among the student population, including various motivators for participation and predictors of problematic play. The study examined a self-selected sample of student online poker players using an online survey (n=422). Results showed that online poker playing was undertaken at least twice per week by a third of the participants. Almost one in five of the sample (18%) was defined as a problem gambler using the DSM-IV criteria. Findings demonstrated that problem gambling in this population was best predicted by negative mood states after playing, gender swapping whilst playing, and playing to escape from problems.     

Psychology of communication technology use in the workplace.

It is generally understood that employees in organizations misuse technology in specific ways--by sending and receiving personal email, frequenting chat rooms, and using the Web for non-work-related reasons. However, little research has focused on what motivates this type of use. The present study extends existing communication technology and organizational literatures by going beyond usage assessments and examining how an employee's psychological state influences motivations for non-work-related communication technology use during company time.