Can understanding reward help illuminate anhedonia?

Purpose of review: The goal of this paper is to examine how reward processing might help us understand the symptom of anhedonia. Recent findings: There are extensive reviews exploring the relationship between responses to rewarding stimuli and depression. These often include a discussion on anhedonia and how this might be underpinned in particular by dysfunctional reward processing. However, there is no specific consensus on whether studies to date have adequately examined the various sub-components of reward processing or how these might relate in turn to various aspects of anhedonia symptoms. Summary: The approach to understanding the symptom of anhedonia should be to examine all the sub-components of reward processing at the subjective and objective behavioural and neural level, with well validated tasks that can be replicated. Investigating real life experiences of anhedonia and how theses might be predicted by objective lab measures is also needed in future research

Disrupted habenula function in major depression.

The habenula is a small, evolutionarily conserved brain structure that plays a central role in aversive processing and is hypothesised to be hyperactive in depression, contributing to the generation of symptoms such as anhedonia. However, habenula responses during aversive processing have yet to be reported in individuals with major depressive disorder (MDD). Unmedicated and currently depressed MDD patients (N=25, aged 18-52 years) and healthy volunteers (N=25, aged 19-52 years) completed a passive (Pavlovian) conditioning task with appetitive (monetary gain) and aversive (monetary loss and electric shock) outcomes during high-resolution functional magnetic resonance imaging; data were analysed using computational modelling. Arterial spin labelling was used to index resting-state perfusion and high-resolution anatomical images were used to assess habenula volume. In healthy volunteers, habenula activation increased as conditioned stimuli (CSs) became more strongly associated with electric shocks. This pattern was significantly different in MDD subjects, for whom habenula activation decreased significantly with increasing association between CSs and electric shocks. Individual differences in habenula volume were negatively associated with symptoms of anhedonia across both groups. MDD subjects exhibited abnormal negative task-related (phasic) habenula responses during primary aversive conditioning. The direction of this effect is opposite to that predicted by contemporary theoretical accounts of depression based on findings in animal models. We speculate that the negative habenula responses we observed may result in the loss of the capacity to actively avoid negative cues in MDD, which could lead to excessive negative focus

Assessment of Cognitive Symptom Validity in Acquired Brain Injury

Aim: The formal assessment of symptom validity is increasingly regarded as good practice in the neuropsychological assessment of adult patients presenting with cognitive complaints after head injury. Typical assessment tools include relatively easy memory tests for which pass rates are expected to be hig h, even in patients with significant neuropathology . Such assessments are more rarely conducted in the paediatric population and it is often ass umed that rates of poor effort or exag ge rated symptoms are lower or more readily detect ed without recourse to formal tests. We report two recent studies exploring the use of effort testin g in paediatric neuropsychological assessment. Methods and Results: In stu dy 1, non-injured children were ask ed to simula te rates of underperforman ce. While symp tom validity tests appeared sensiti ve to underperformance in young children, patterns of simulated underperformance dif fered qualitatively and quantitatively betw een young (6– 8- y-olds) and older child ren (9–11-y-old s). In study 2, Symptom Validity Tests were used with a clinically referred sam ple of chil dren and adolescents wit h acquir ed brain injury. The prevalence of likely invalid or exaggerated un derperformance was examined in a group at identified risk of malingering (i.e. those with clear evid ence of external incentive to underperform such as an active medico-legal compensat ion clai m, school avoidance or other clear sec ondary gain – Slick and Sherman, in press) versus those assessed at lo w risk. Conclusion: The application of formal symptom validity testi ng within paediatric practice is discussed with consid- eratio n given to both the practical and the ethical dimen- sions of using this approach in the assessment of children and young people

Innovative techniques and tools for public participation in U.S. Department of Energy programs

In early 1995, Jon Yerxa, Public Involvement Team Leader in the Office of External Affairs at the US Department of Energy (DOE) Richland Operations Office, identified the need to ``provide Hanford`s Public Participation Program with input and advice concerning public involvement issues at Hanford.`` Yerxa identified the following committees: (1) Training, (2) Tri-Party Agreement/NEPA/ Environmental Justice, (3) Program, (4) Performance Evaluation, and (5) Communications Techniques and Technology. These committees were to be staffed by public involvement and communications staff from DOE and its contractors on the Hanford Site. This report describes the activities and recommendations of the Communications Techniques and Technology committee

Pharmacology Update

Neuropathic pain in a common problem encountered in palliative care. When neuropathic pain is diagnosed, appropriate treatment is important in limiting the severe psychosocial impairment that can ensue with undertreated pain. Proper evaluation of the patient to clarify the type of pain experienced is the first step to determine appropriate management. Tapentadol is an oral mu-opioid receptor agonist and a noradrenaline reuptake inhibitor developed by Ortho-McNeil Janssen Pharmaceuticals and approved by the Food and Drug Administration in November 2008 for the treatment of moderate-to-severe acute pain in adult patients and for chronic pain in August 2011 in an extended release form. Tapentadol has been studied for use in nociceptive pain but few studies have yet been done to assess its efficacy in the treatment of neuropathic pain

The impact of experimental sleep restriction on affective functioning in social and nonsocial contexts among adolescents.

BackgroundShort sleep duration is highly prevalent in adolescence, and it prospectively predicts problems with emotional adjustment and psychiatric health. To move beyond epidemiological associations and inform models of developmental psychopathology, we experimentally restricted sleep to observe impacts on affective functioning. Based on the importance of social contexts to adolescent emotional experiences, we also examined the impact of restricted sleep on socioaffective functioning in an ecologically valid peer interaction task.MethodsIn Study 1, adolescents (ages 11.5-15.0, n = 48) were randomly assigned to two nights of polysomnography-monitored sleep restriction (4 hr in bed) or extension (10 hr in bed). One week later, they completed the other sleep manipulation. Affective functioning was assessed by self-report and pupil response to standardized affective sounds. Study 2 used a similar protocol and invited adolescents (ages 12-15.0, n = 16) to the sleep laboratory along with 2-4 friends to observe affective behavior in a social context primed for peer conflict. Mixed effects models were used to evaluate the effect of sleep condition on affective outcomes.ResultsStudy 1 demonstrated increased negative affect following sleep restriction, relative to extension, on self-report (p = .02) and pupil measures (p = .01). Study 2 replicated these effects (both p = .04) and demonstrated greater negative affective behavior in a peer social context (p = .01). Exploratory analyses for positive affect showed reductions as assessed by self-report (p = .005), but not pupil (p = .81), in Study 1; and no significant effects in Study 2 (self-report, p = .14; pupil, p = .29; positive affective behavior, p = .43).ConclusionsExperimental sleep restriction in adolescence impacts negative affective functioning as evidenced by self-report and pupil reactivity, as well as observed behavior in a social context primed for peer conflict. Implications for the impact of short sleep on developmental trajectories of emotional adjustment and psychiatric health, and opportunities for early intervention, are briefly discussed