Prospective memory impairments in Alzheimer's Disease and behavioral variant frontotemporal dementia: Clinical and neural correlates

BACKGROUND: Prospective memory (PM) refers to a future-oriented form of memory in which the individual must remember to execute an intended action either at a future point in time (Time-based) or in response to a specific event (Event-based). Lapses in PM are commonly exhibited in neurodegenerative disorders including Alzheimer's disease (AD) and frontotemporal dementia (FTD), however, the neurocognitive mechanisms driving these deficits remain unknown. OBJECTIVE: To investigate the clinical and neural correlates of Time- and Event-based PM disruption in AD and the behavioral-variant FTD (bvFTD). METHODS: Twelve AD, 12 bvFTD, and 12 healthy older Control participants completed a modified version of the Cambridge Prospective Memory test, which examines Time- and Event-based aspects of PM. All participants completed a standard neuropsychological assessment and underwent whole-brain structural MRI. RESULTS: AD and bvFTD patients displayed striking impairments across Time- and Event-based PM relative to Controls, however, Time-based PM was disproportionately affected in the AD group. Episodic memory dysfunction and hippocampal atrophy was found to correlate strongly with PM integrity in both patient groups, however, dissociable neural substrates were also evident for PM performance across dementia syndromes. CONCLUSION: Our study reveals the multifaceted nature of PM dysfunction in neurodegenerative disorders, and suggests common and dissociable neurocognitive mechanisms, which subtend these deficits in each patient group. Future studies of PM disturbance in dementia syndromes will be crucial for the development of successful interventions to improve functional independence in the patient's daily life

Vintage venoms: proteomic and pharmacological stability of snake venoms stored for up to eight decades

For over a century, venom samples from wild snakes have been collected and stored around the world. However, the quality of storage conditions for "vintage" venoms has rarely been assessed. The goal of this study was to determine whether such historical venom samples are still biochemically and pharmacologically viable for research purposes, or if new sample efforts are needed. In total, 52 samples spanning 5 genera and 13 species with regional variants of some species (e.g., 14 different populations of Notechis scutatus) were analysed by a combined proteomic and pharmacological approach to determine protein structural stability and bioactivity. When venoms were not exposed to air during storage, the proteomic results were virtually indistinguishable from that of fresh venom and bioactivity was equivalent or only slightly reduced. By contrast, a sample of Acanthophis antarcticus venom that was exposed to air (due to a loss of integrity of the rubber stopper) suffered significant degradation as evidenced by the proteomics profile. Interestingly, the neurotoxicity of this sample was nearly the same as fresh venom, indicating that degradation may have occurred in the free N- or C-terminus chains of the proteins, rather than at the tips of loops where the functional residues are located. These results suggest that these and other vintage venom collections may be of continuing value in toxin research. This is particularly important as many snake species worldwide are declining due to habitat destruction or modification. For some venoms (such as N. scutatus from Babel Island, Flinders Island, King Island and St. Francis Island) these were the first analyses ever conducted and these vintage samples may represent the only venom ever collected from these unique island forms of tiger snakes. Such vintage venoms may therefore represent the last remaining stocks of some local populations and thus are precious resources. These venoms also have significant historical value as the Oxyuranus venoms analysed include samples from the first coastal taipan (Oxyuranus scutellatus) collected for antivenom production (the snake that killed the collector Kevin Budden), as well as samples from the first Oxyuranus microlepidotus specimen collected after the species' rediscovery in 1976. These results demonstrate that with proper storage techniques, venom samples can retain structural and pharmacological stability. This article is part of a Special Issue entitled: Proteomics of non-model organisms. Biological significance: •These results show that with proper storage venoms are useful for decades.•These results have direct implications for the use of rare venoms

Child and Family Therapy Process: Concordance of Therapist and Observational Perspectives

The objective of this study is to examine the characteristics of outpatient mental health services delivered in community-based outpatient clinics, comparing information obtained from two different sources, therapists serving children and families, and observational coders viewing tapes of the same treatment sessions. Videotaped therapy sessions were rated by therapists and independent coders regarding goals and strategies pursued during each session. Sixty-three sessions were taped of outpatient care provided to 18 children and their caregivers by 11 therapists. Children were 4–13 years old and families were receiving services at least in part due to reported child behavior problems, confirmed by ratings from the Child Behavior Checklist and Conners Parent Rating Scale—Revised. Analyses assessed the frequency, type, and intensity of goals and strategies pursued in therapy sessions from both therapist and observational coders’ perspectives. Reliability of observer ratings and correspondence between therapist and observer reports were also examined. The reliability of observational coding of goals and strategies was moderate to good, with 76% of 39 codes having ICCs of .5 or greater. Therapists reported pursuing 2.5 times more goals and strategies per session, on average, than identified by observational coders. Correspondence between therapists and coders about the occurrence of specific goals and strategies in treatment sessions was low, with 20.5% of codes having a Kappa of .4 or higher. Substantial differences exist in what therapists and independent coders report as occurring in outpatient treatment sessions. Both perspectives suggest major differences between the content of services provided in community-based outpatient clinics and the structure of evidence-based programs, which emphasize intense pursuit of a small number of goals and strategies in each treatment session. Implications of the findings for quality improvement efforts in community-based mental health care settings are discussed

The role of simulation in intertemporal choices

One route to understanding the thoughts and feelings of others is by mentally putting one's self in their shoes and seeing the world from their perspective, i.e., by simulation. Simulation is potentially used not only for inferring how others feel, but also for predicting how we ourselves will feel in the future. For instance, one might judge the worth of a future reward by simulating how much it will eventually be enjoyed. In intertemporal choices between smaller immediate and larger delayed rewards, it is observed that as the length of delay increases, delayed rewards lose subjective value; a phenomenon known as temporal discounting. In this article, we develop a theoretical framework for the proposition that simulation mechanisms involved in empathizing with others also underlie intertemporal choices. This framework yields a testable psychological account of temporal discounting based on simulation. Such an account, if experimentally validated, could have important implications for how simulation mechanisms are investigated, and makes predictions about special populations characterized by putative deficits in simulating others

The association between past and future oriented thinking: Evidence from autism spectrum disorder

A number of recently developed theories (e.g., the constructive episodic simulation, self-projection, and scene construction hypotheses) propose that the ability to simulate possible future events (sometimes referred to as episodic future thinking, prospection, or foresight) depends on the same neurocognitive system that is implicated in the recall of past events (episodic memory). In this paper, we argue that autism spectrum disorder (ASD) offers an ideal test of such theories, given that it is a developmental disorder that is characterized by impairments in episodic memory. Each of these theories would predict concomitant impairments in episodic future thinking among individuals with ASD. We review evidence concerning episodic future thinking in ASD, as well as studies of prospective memory (remembering to do something in the future), planning, navigation, and theory of mind, which some theories suggest also rely on the same mechanism as episodic future thinking

Cost and Outcome of BehaviouRal Activation (COBRA) : a randomised controlled trial of behavioural activation versus cognitive–behavioural therapy for depression

Background Depression is a common, debilitating and costly disorder. The best-evidenced psychological therapy – cognitive–behavioural therapy (CBT) – is complex and costly. A simpler therapy, behavioural activation (BA), may be an effective alternative. Objectives To determine the clinical effectiveness and cost-effectiveness of BA compared with CBT for depressed adults at 12 and 18 months’ follow-up, and to investigate the processes of treatments. Design Randomised controlled, non-inferiority trial stratified by depression severity, antidepressant use and recruitment site, with embedded process evaluation; and randomisation by remote computer-generated allocation. Setting Three community mental health services in England. Participants Adults aged ≥ 18 years with major depressive disorder (MDD) recruited from primary care and psychological therapy services. Interventions BA delivered by NHS junior mental health workers (MHWs); CBT by NHS psychological therapists. Outcomes Primary: depression severity (as measured via the Patient Health Questionnaire-9; PHQ-9) at 12 months. Secondary: MDD status; number of depression-free days; anxiety (as measured via the Generalised Anxiety Disorder-7); health-related quality of life (as measured via the Short Form questionnaire-36 items) at 6, 12 and 18 months; and PHQ-9 at 6 and 18 months, all collected by assessors blinded to treatment allocation. Non-inferiority margin was 1.9 PHQ-9 points. We undertook intention-to-treat (ITT) and per protocol (PP) analyses. We explored cost-effectiveness by collecting direct treatment and other health- and social-care costs and calculating quality-adjusted life-years (QALYs) using the EuroQol-5 Dimensions, three-level version, at 18 months. Results We recruited 440 participants (BA, n = 221; CBT, n = 219); 175 (79%) BA and 189 (86%) CBT participants provided ITT data and 135 (61%) BA and 151 (69%) CBT participants provided PP data. At 12 months we found that BA was non-inferior to CBT {ITT: CBT 8.4 PHQ-9 points [standard deviation (SD) 7.5 PHQ-9 points], BA 8.4 PHQ-9 points (SD 7.0 PHQ-9 points), mean difference 0.1 PHQ-9 points, 95% confidence interval (CI) –1.3 to 1.5 PHQ-9 points, p = 0.89; PP: CBT 7.9 PHQ-9 points (SD 7.3 PHQ-9 points), BA 7.8 PHQ-9 points (SD 6.5 PHQ-9 points), mean difference 0.0 PHQ-9 points, 95% CI –1.5 to 1.6 PHQ-9 points, p = 0.99}. We found no differences in secondary outcomes. We found a significant difference in mean intervention costs (BA, £975; CBT, £1235; p Limitations In this pragmatic trial many depressed participants in both groups were also taking antidepressant medication, although most had been doing so for a considerable time before entering the trial. Around one-third of participants chose not to complete a PP dose of treatment, a finding common in both psychotherapy trials and routine practice. Conclusions We found that BA is as effective as CBT, more cost-effective and can be delivered by MHWs with no professional training in psychological therapies. Future work Settings and countries with a paucity of professionally qualified psychological therapists, might choose to investigate the delivery of effective psychological therapy for depression without the need to develop an extensive and costly professional infrastructure.</p

A prospective investigation of rumination and executive control in predicting overgeneral autobiographical memory in adolescence

The CaR-FA-X model (Williams et al., 2007), or capture and rumination (CaR), functional avoidance (FA) and impaired executive control (X), is a model of overgeneral autobiographical memory. Two mechanisms of the model, rumination and executive control were examined in isolation and in interaction to investigate overgeneral autobiographical memory over time. Method: Across two time points, six months apart, a total of 149 adolescents (13-16 years) completed a minimal instruction autobiographical memory test, a measure of executive control with emotional and non-emotional stimuli, and measures of brooding rumination and reflective pondering. Results: It was found that executive control for emotional information was negatively associated with OGM, but only when reflective pondering levels were high. Conclusion: In the context of higher levels of reflective pondering, greater switch costs (i.e. lower executive control) when processing emotional information predict a decrease in OGM over time

Improving care for people with dementia: development and initial feasibility study for evaluation of life story work in dementia care

Background: Improving dementia care quality is an urgent priority nationally and internationally. Life story work (LSW) is an intervention that aims to improve individual outcomes and care for people with dementia and their carers. LSW gathers information and artefacts about the person, their history and interests, and produces a tangible output: the ‘life story’. Objective: To establish whether or not full evaluation of LSW was feasible. Design: Mixed-methods feasibility study. Methods: In-depth interviews and focus groups explored experiences of LSW and best practice with people with dementia, family members and dementia care staff. A systematic review explored best practice and theories of change for LSW. These stages helped to identify the outcomes and resources to explore in the feasibility study. A representative sample survey of health and social care dementia care providers in England established LSW practice in different settings. A survey of a self-selected sample of family members of people with dementia explored how LSW is experienced. Two small outcome studies (stepped-wedge study in six care homes and pre-test post-test study in inpatient specialist dementia care wards) explored the feasibility of full evaluation of LSW in these settings. Settings: Survey: generalist and specialist care homes; NHS dementia care settings; and community dementia services. Feasibility study: care homes and NHS inpatient dementia care wards. Participants: NHS and social care services, people with dementia, family carers, care home staff and NHS staff. Interventions: LSW. Main outcome measures: Spread of LSW and good practice, quality of life (QoL) for the person with dementia and carers, relationships between people with dementia and family carers, staff attitudes about dementia, staff burnout, resource use and costs. Review methods: Narrative review and synthesis, following Centre for Review and Dissemination guidelines. Results: Good practice in LSW is identifiable, as are theories of change about how it might affect given outcomes. Indicators of best practice were produced. LSW is spreading but practice and use vary between care settings and are not always in line with identified good practice. Two different models of LSW are evident; these are likely to be appropriate at different stages of the dementia journey. The feasibility study showed some positive changes in staff attitudes towards dementia and, for some people with dementia, improvements in QoL. These may be attributable to LSW but these potential benefits require full evaluation. The feasibility work established the likely costs of LSW and highlighted the challenges of future evaluation in care homes and inpatient dementia care settings. Limitations: There was insufficient evidence in the literature to allow estimation of outcome size. We did not carry out planned Markov chain modelling to inform decisions about carrying out future evaluation because of the dearth of outcome data in the literature; low levels of data return for people with dementia in the hospital settings; lack of detected effect for most people with dementia; and questions about implementation in the research settings. Conclusions: LSW is used across different health and social care settings in England, but in different ways, not all of which reflect ‘good practice’. This large, complex study identified a wide range of challenges for future research, but also the possibility that LSW may help to improve care staff attitudes towards dementia and QoL for some people with dementia. Future work: Full evaluation of LSW as an intervention to improve staff attitudes and care is feasible with researchers based in or very close to care settings to ensure high-quality data collection. Funding: The National Institute for Health Research Health Services and Delivery Research programme. Keywords