Mind’s eye: The impact of spider presence and cognitive therapy on size estimation biases in spider phobia

The present study assessed the circumstances under which size estimation biases in spider phobia occur, and whether such biases are modifiable by treatment. Women with (n = 67) and without (n = 33) spider phobia approached a spider during a behavioral approach test (BAT). They provided size estimates of the spider both during and shortly after the BAT (with the spider in view, or not in view, respectively). Phobic women then received cognitive therapy or a placebo treatment and one week later they underwent a second BAT and provided size estimates of the same spider during and after the BAT. Phobic women reported larger size estimates than non-phobic women after, but not during, the BAT. Size estimates after, but not during, the BAT correlated with self-reported fear but not avoidance. Size estimates after, but not during, the BAT reduced from the first to second BAT in phobic women; an effect evident in both the cognitive therapy and placebo treatment conditions. Changes in size estimates were not associated with treatment-induced reductions in fear or avoidance. These results suggest that estimation biases in spider phobia are likely driven by non-perceptual processes. The clinical utility of size estimation measures is discussed.     

A network analysis of two conceptual approaches to the etiology of PTSD

Two prominent conceptual models of posttraumatic stress disorder (PTSD) are the cognitive model, associated with cognitive processing therapy (CPT; Resick & Schnicke, 1992), and the functional contextualist model, underlying acceptance and commitment therapy (ACT; Hayes et al., 1999). Network analysis was used to examine dynamic interactions among cognitive (relating to CPT) and functional contextualistic (relating to ACT) variables and PTSD symptoms in a sample of 722 trauma-exposed adults. Results from the cognitive networks highlighted the importance of maladaptive beliefs about threat in maintaining the co-occurrence of PTSD symptoms and cognitive variables. Additionally, PTSD symptoms were more likely to lead to cognitive variables, rather than the reverse direction. Results from the functional contextualist networks identified numerous associations amongst variables that contribute to the co-occurrence of PTSD symptoms and psychological inflexibility. Findings from this study may help generate causal hypotheses that can be tested further using a longitudinal study design.     

Towards measurement of the Healthy Ageing Phenotype in lifestyle-based intervention studies

Introduction

Given the biological complexity of the ageing process, there is no single, simple and reliable measure of how healthily someone is ageing. Intervention studies need a panel of measures which capture key features of healthy ageing. To help guide our research in this area, we have adopted the concept of the “Healthy Ageing Phenotype” (HAP) and this study aimed to (i) identify the most important features of the HAP and (ii) identify/develop tools for measurement of those features.

Methods

After a comprehensive assessment of the literature we selected the following domains: physiological and metabolic health, physical capability, cognitive function, social wellbeing, and psychological wellbeing which we hoped would provide a reasonably holistic characterisation of the HAP. We reviewed the literature and identified systematic reviews and/or meta-analysis of cohort studies, and clinical guidelines on outcome measures of these domains relevant to the HAP. Selection criteria for these measures included: frequent use in longitudinal studies of ageing; expected to change with age; evidence for strong association with/prediction of ageing-related phenotypes such as morbidity, mortality and lifespan; whenever possible, focus on studies measuring these outcomes in populations rather than on individuals selected on the basis of a particular disease; (bio)markers that respond to (lifestyle-based) intervention. Proposed markers were exposed to critique in a Workshop held in Newcastle, UK in October 2012.

Results

We have selected a tentative panel of (bio)markers of physiological and metabolic health, physical capability, cognitive function, social wellbeing, and psychological wellbeing which we propose may be useful in characterising the HAP and which may have utility as outcome measures in intervention studies. In addition, we have identified a number of tools which could be applied in community-based intervention studies designed to enhance healthy ageing.

Conclusions

We have proposed, tentatively, a panel of outcome measures which could be deployed in community-based, lifestyle intervention studies. The evidence base for selection of measurement domains is less well developed in some areas e.g. social wellbeing (where the definition of the concept itself remains elusive) and this has implications for the identification of appropriate tools. Although we have developed this panel as potential outcomes for intervention studies, we recognise that broader agreement on the concept of the HAP and on tools for its measurement could have wider utility and e.g. could facilitate comparisons of healthy ageing across diverse study designs and populations.     

Stress hormones,sleep deprivation and cognition in older adults

Cognition can be deteriorated in older persons because of several potential mechanisms including the hormonal changes occurring with age. Stress events cause modification in hormonal balance with acute and chronic changes such as increase in cortisol and thyroid hormones, and simultaneous alterations in dehydroepiandrosterone sulphate, testosterone and insulin like growth factor-1 levels. The ability to cope with stress and regain previous healthy status, also called resiliency, is particularly impaired in older persons Thus, stressful conditions and hormonal dysregulation might concur to the onset of cognitive impairment in this population.     

On the physiology of cognitive decline in type 1 diabetes

ObjectivesType 1 diabetes mellitus (T1DM) may be associated with cognitive impairment and notably a decline in psychomotor speed, information processing speed and attention. The mechanism for this decline is uncertain. Previous studies by our group and others have demonstrated a decline in EEG-power and event-related potential amplitude in T1DM. The objectives of the present study were to explore whether 1) the association between event-related potential (N100) amplitude and psychomotor speed is different between T1DM and healthy subjects, and 2) the decline in N100 amplitude depends on duration of diabetes.MethodsPatients with T1DM (N = 204) and healthy control subjects (N = 358) were included in a cross-sectional study. Event-related brain potentials were recorded with auditory reaction tasks. Psychomotor speed was evaluated with the Grooved Pegboard test in a subset of the patients (N = 70) and the healthy control subjects (N = 89).ResultsPatients with T1DM had a decrease in the N100 amplitude that correlated with a decline in psychomotor speed, longer duration of diabetes and increasing age. In healthy controls, the N100 amplitude did not decrease with age and the association between psychomotor speed and N100 amplitude was absent.ConclusionThe association between psychomotor speed and N100 amplitude is likely to be a specific trait for T1DM since it was not found in healthy controls and was dependent on diabetes duration. Our findings indicate that the pathogenesis of cognitive decline in T1DM may involve a disease-related factor with a long-term influence on the N100 amplitude.     

Perception-action integration in young age—A cross-sectional EEG study

Humans differ in their capacity for integrating perceived events and related actions. The “Theory of event coding” (TEC) conceptualizes how stimuli and actions are cognitively bound into a common functional representation (or “code”), known as the “event file”. To date, however, the neural processes underlying the development of event file coding mechanisms across age are largely unclear. We investigated age-related neural changes of event file coding from late childhood to early adulthood, using EEG signal decompositions methods. We included a group of healthy participants (n = 91) between 10 and 30 years, performing an event file paradigm. Results of this study revealed age-related effects on event file coding processes both at the behavioural and the neurophysiological level. Performance accuracy data showed that event file unbinding und rebinding processes become more efficient from late childhood to early adulthood. These behavioural effects are reflected by age-related effects in two neurophysiological subprocesses associated with the superior parietal cortex (BA7) as revealed in the analyses using EEG signal decomposition. The first process entails mapping and association processes between stimulus and response; whereas, the second comprises inhibitory control subprocesses subserving the selection of the relevant motor programme amongst competing response options.