This issue contains two invited reviews, sets of papers examining various aspects of depression, anxiety disorders, and trauma/stress exposure and individual articles examining suicide, development of psychosis, and measurement of spirituality.

Depression is well recognized to be rooted in the down-regulation of positive affect systems. This paper reviews some of the social and non-social theories that seek to explain the potential adaptive advantages of being able to tone down positive affect, and how dysfunctions in such affect control can occur in some contexts. Common to most evolutionary theories of depression is the view that loss of control over aversive events and/or major resources/rewards exert downward pressure on positive affect. Social theories, however, suggest that it is loss of control over the social environment that is particularly depressogenic. Two evolutionary theories (the attachment-loss, and the defeat-loss theories) are briefly reviewed and their interaction considered. It is suggested that phenotypes for toning down positive affect, in the face of loss of control, may become more severe in the context of socially hostile, unsupportive and/or excessively competitive environments. The paper briefly considers how human competencies for self-evaluation in relation to others, rumination, self-criticism, and modern social contexts can accentuate dysfunctional expressions of affect regulation.

Background. Risk-taking behavior is a major cause of morbidity and mortality in adolescence. In the context of decision theory and motivated (goal-directed) behavior, risk-taking reflects a pattern of decision-making that favors the selection of courses of action with uncertain and possibly harmful consequences. We present a triadic, neuroscience systems-based model of adolescent decision-making.

Method. We review the functional role and neurodevelopmental findings of three key structures in the control of motivated behavior, i.e. amygdala, nucleus accumbens, and medial/ventral prefrontal cortex. We adopt a cognitive neuroscience approach to motivated behavior that uses a temporal fragmentation of a generic motivated action. Predictions about the relative contributions of the triadic nodes to the three stages of a motivated action during adolescence are proposed.

Results. The propensity during adolescence for reward/novelty seeking in the face of uncertainty or potential harm might be explained by a strong reward system (nucleus accumbens), a weak harm-avoidant system (amygdala), and/or an inefficient supervisory system (medial/ventral prefrontal cortex). Perturbations in these systems may contribute to the expression of psychopathology, illustrated here with depression and anxiety.

Conclusions. A triadic model, integrated in a temporally organized map of motivated behavior, can provide a helpful framework that suggests specific hypotheses of neural bases of typical and atypical adolescent behavior.

Background. Implicit learning through motor sequencing tasks is sensitive to basal ganglia dysfunction. Consequently, it is ideally suited for testing elements of the frontostriatal model of major depression and performance can be related to key clinical, neuropsychological, vascular and biochemical data.

Method. Twenty-one subjects with moderate to severe unipolar depression and 21 age-, sex- and education-matched controls were recruited. Clinical, vascular and biochemical data were recorded. Subjects were administered a battery of neuropsychological tests that assessed speed of processing, working memory, learning, memory, language, perceptual organization and executive functioning. Additionally, subjects were administered a motor sequencing implicit learning task. Implicit learning is assumed when reaction times improve during the sequenced condition as compared to the pseudo-random baseline condition.

Results. The rate of implicit learning in persons with depression was only half that of control subjects (3·6% v. 7·3%). Lower rates of implicit learning in patients were associated with poorer performance on neuropsychological tests of visuomotor speed and mental flexibility, longer duration of depressive episode and severity of acute stress. In a small number of subjects, poorer performance was also related to past suicide attempt.

Conclusions. Impaired implicit learning in persons with depression is consistent with frontostriatal dysfunction. Performance is related to some clinical characteristics and to neuropsychological functioning on tests of visuomotor speed and mental flexibility.

Background. The purpose of the study was to examine whether the addition of a brief individual self-help package to standard primary-care treatment of depression with antidepressants is associated with any additional improvements in clinical outcome.

Method. Individuals with major depressive disorder who were prescribed an antidepressant were recruited through their general practitioner (GP) and allocated randomly to standard treatment alone or standard treatment plus self-help. Assessments of symptoms, social adjustment, global functioning, satisfaction with treatment and knowledge about the management of the disorder were completed at three time points over 26 weeks.

Results. One hundred and twelve individuals agreed to participate and 96 met criteria for inclusion in the randomized controlled trial. Subjects in both treatment conditions improved substantially over the study period; the mean Beck Depression Inventory (BDI) score fell from 27·3 to 13·9 in the intention-to-treat analysis. There were no between group differences in outcome on any of the primary outcome measures, nor did these approach even marginal significance. Patients and GPs were highly satisfied with the self-help programme, and the intervention as compared to the control group reported significantly greater improvements in knowledge about depression and satisfaction with information received about depression.

Conclusions. An individualized self-help package improved perceived knowledge about depression but did not have identifiable effects on outcome when offered to patients treated in primary care. The study was sufficiently well powered to detect relatively small effects.

Background. Prevalence of childhood anxiety disorders at specific ages and genetic etiological influences on anxiety disorders in young children have been little studied. The present study reports prevalence estimates in a community sample of 6-year-old twins, and patterns of genetic and environmental influences on these early-onset anxiety disorders.

Method. Using a two-phase design 4662 twin-pairs were sampled and 854 pairs were assessed in the second phase by maternal-informant diagnostic interview using DSM-IV criteria.

Results. The most common conditions were separation anxiety disorder (SAD) [2·8%, 95% confidence interval (CI) 2·1–3·8, for current disorder] and specific phobia (10·8%, 95% CI 8·4–13·6, for current disorder). Behavioral genetic modeling was feasible for these two conditions, applied to two phenotypes: symptom syndrome (regardless of impairment) and the narrower one of diagnostic status (symptom syndrome with associated impairment). The heritability estimate for SAD diagnostic status was high, 73%, with remaining variance attributed to non-shared environment. The heritability estimates for specific phobia were also high, 80% for the symptom syndrome and 60% for diagnostic status, with remaining variance attributed in both cases to non-shared environment.

Conclusions. Compared with previous epidemiological surveys of children and adolescents in wide age-bands, the current estimates suggest that rates of anxiety disorders assessed in young childhood are generally at least as high and perhaps higher compared with those found in older children. The heritability estimates suggest that the genetic effects on these early-onset anxiety disorders are substantial and more significant than environmental effects, whether shared or non-shared.

Background. Most research has indicated that neuroticism (or trait anxiety) is associated with only negative outcomes. Such a common, heritable and variable trait is expected to have beneficial as well as detrimental effects. We tested the hypothesis that trait anxiety in childhood reduces the risk of dying from accidental causes in early adult life.

Method. A longitudinal, population-based, birth cohort study of 4070 men and women born in the UK in 1946. Trait anxiety as judged by teachers when the participants were 13 and 15 years old, and the neuroticism scale of a Maudsley Personality Inventory (MPI) when the participants were 16 years old. Outcomes were deaths, deaths from accidents, non-fatal accidents, and non-fatal accidents requiring medical intervention.

Results. Adolescents with low trait anxiety had higher rates of accident mortality to age 25 [low anxiety at 13, hazard ratio (HR) 5·9, low anxiety at 15, HR 1·8]. Low trait anxiety in adolescence was associated with decreased non-accidental mortality after age 25 (low anxiety at 13, HR 0; low anxiety at 15, HR 0·7; low neuroticism at 16, HR 0·7).

Conclusions. High trait anxiety measured in adolescence is associated with reduced accidents and accidental death in early adulthood but higher rates of non-accidental mortality in later life.

Background. Panic disorder is a prevalent, often disabling, disorder among primary-care patients, but there are large gaps in quality of treatment in primary care. This study describes the incremental cost-effectiveness of a combined cognitive behavioral therapy (CBT) and pharmacotherapy intervention for patients with panic disorder versus usual primary-care treatment.

Method. This randomized control trial recruited 232 primary-care patients meeting DSM-IV criteria for panic disorder from March 2000 to March 2002 from six primary-care clinics from university-affiliated clinics at the University of Washington (Seattle) and University of California (Los Angeles and San Diego). Patients were randomly assigned to receive either treatment as usual or a combined CBT and pharmacotherapy intervention for panic disorder delivered in primary care by a mental health therapist. Intervention patients had up to six sessions of CBT modified for the primary-care setting in the first 12 weeks, and up to six telephone follow-ups over the next 9 months. The primary outcome variables were total out-patient costs, anxiety-free days (AFDs) and quality adjusted life-years (QALYs).

Results. Relative to usual care, intervention patients experienced 60·4 [95% confidence interval (CI) 42·9–77·9] more AFDs over a 12-month period. Total incremental out-patient costs were $492 higher (95% CI $236–747) in intervention versus usual care patients with a cost per additional AFD of $8.40 (95% CI $2.80–14.0) and a cost per QALY ranging from $14158 (95% CI $6791–21496) to $24776 (95% CI $11885–37618). The cost per QALY estimate is well within the range of other commonly accepted medical interventions such as statin use and treatment of hypertension.

Conclusions. The combined CBT and pharmacotherapy intervention was associated with a robust clinical improvement compared to usual care with a moderate increase in ambulatory costs.

Background. Aggressiveness on the roads and/or anger behind the wheel are considered to be a major traffic safety problem in several countries. However, the psychological mechanisms of anger and/or aggression on the roads remain largely unclear. This study examines a large cohort of French employees followed over the period 1994–2001 to establish whether psychometric measures of aggression/hostility were significantly associated with an increased risk of an injury accident (I-A). An I-A was defined as a traffic accident in which someone was injured, that is required medical care.

Method. A total of 11754 participants aged from 39 to 54 years in 1993 were included in this study. Aggression/hostility was measured in 1993 using the French version of the Buss–Durkee Hostility Inventory (BDHI). Driving behaviors and I-A were recorded in 2001. Sociodemographic and alcohol consumption data were available from annual follow-up of the cohort. The relationship between aggression/hostility scores and I-A was assessed using negative binomial regression models with time-dependent covariates.

Results. The overall BDHI scoring was not statistically predictive of subsequent I-A: adjusted rate ratio (aRR) 1·02, 95% confidence interval (CI) 0·81–1·28, for participants with intermediate scores and aRR 1·25, 95% CI 0·98–1·61 for those with high scores, both compared to those with low scores. The only BDHI subscales found to be associated with I-A were ‘irritability’ (aRR 1·33, 95% CI 1·02–1·75 for participants with high scores) and ‘negativism’ (aRR 1·32, 95% CI 1·01–1·71 for participants with high scores).

Conclusion. Overall aggression/hostility personality traits did not predict I-A in this large cohort of French employees, suggesting that aggressiveness on the roads and/or anger behind the wheel extend beyond the individual's general propensity for aggression.

Background. Exploration of the degree to which perceived chronic stress is heritable is important as these self-reports have been linked to stress-related health outcomes. The aims of this study were to estimate whether perceived stress is a heritable condition and to assess whether heritability estimates vary between subjective stress reactivity and stress related to external demands.

Method. A sample of 103 monozygotic and 77 dizygotic twin pairs completed three questionnaires designed to measure perceived stress: the Perceived Stress Scale (PSS), the Measure for the Assessment of Stress Susceptibility (MESA) and the Trier Inventory for the Assessment of Chronic Stress (TICS). The TICS assesses the frequency of stressful experiences on six scales, the MESA assesses subjective stress reactivity, and the PSS takes both factors into account.

Results. A multivariate model-fitting procedure revealed that a model with common additive genetic and shared environmental factors best fit the eight scales (PSS, MESA, six TICS scales). Heritabilities for the best-fitting model varied between 5% and 45%, depending on the scale.

Conclusions. The present data suggest that perceived stress is in part heritable, that nearly half of the covariance between stress scales is due to genetic factors, and that heritability estimates vary considerably, depending on the questionnaire. Beyond methodological considerations that pertain to the validity of the questionnaires, these data suggest that studies assessing the heritability of perceived chronic stress should take the specific questionnaire focus into account.

Background. While pre-trauma personality and mental health measures are risk factors for post-traumatic stress disorder (PTSD), such information is usually obtained following the trauma and can be influenced by post-trauma distress. We used data collected from a community-based survey of young adults before and after a major natural disaster to examine the extent to which participants' traumatic experiences, demographic and pre-trauma risk factors were associated with their screening positive for PTSD when re-interviewed.

Method. A representative selection of 2085 young adults from the Australian Capital Territory and environs, interviewed in 1999 as part of a longitudinal community-based survey, were re-interviewed 3–18 months after a major bushfire had occurred in the region. When re-interviewed, they were asked about their experiences of trauma threat, uncontrollable and controllable traumatic experiences and their reaction to the fire. They were also screened for symptoms of fire-related PTSD experienced in the week prior to interview.

Results. Four-fifths of participants were exposed to the trauma with around 50% reporting having experienced uncontrollable traumatic events. Reporting PTSD symptoms was associated with being female, having less education, poorer mental health and higher levels of neuroticism prior to the trauma. Particular fire experiences, including being evacuated and feeling very distressed during the disaster, were more strongly associated with PTSD symptoms compared with pre-trauma measures.

Conclusions. While demographic and pre-trauma mental health increased the likelihood of reporting PTSD symptoms, exposure to trauma threat and reaction to the trauma made greater contributions in explaining such symptoms as a result of this disaster.

Background. Deliberate self-harm (DSH) may be associated with increased risk of death from a variety of causes, not just suicide.

Method. A follow-up study of 11583 DSH patients who presented to a general hospital over a 20-year period was conducted to examine risk of death from a range of causes during a follow-up period of between 3 and 23 years. Deaths were identified through national death registries. Expected numbers of deaths were calculated from national death statistics.

Results. The number of deaths (1185, 10·2%) was 2·2 times the expected number, the excess being significantly greater in males than females. Suicides were 17 times more frequent than expected and undetermined causes of death and accidental poisonings 15 times more frequent. Significantly more than expected numbers of deaths from most natural causes were found, including respiratory disease, circulatory, neurological, endocrine, digestive, skin and musculoskeletal and connective tissue disorders, and symptoms, signs and ill-defined conditions. Deaths due to accidents other than poisoning were more frequent than expected in both genders and homicides more frequent in males.

Conclusions. In addition to increased risk of suicide, DSH patients are at increased risk of dying from a wide range of other causes. Possible explanations include lifestyle factors, physical disorders contributing to initial risk of DSH, and social disadvantage. The findings are relevant to clinical management and evaluation of outcome and health-care costs associated with DSH.

Background. The urban environment may increase the risk for psychotic disorder in interaction with pre-existing risk for psychosis, but direct confirmation has been lacking. The hypothesis was examined that the outcome of subclinical expression of psychosis during adolescence, as an indicator of psychosis-proneness, would be worse for those growing up in an urban environment, in terms of having a greater probability of psychosis persistence over a 3·5-year period.

Method. A cohort of 918 adolescents from the Early Developmental Stages of Psychopathology Study (EDSP), aged 14–17 years (mean 15·1 years), growing up in contrasting urban and non-urban environments, completed a self-report measure of psychotic symptoms at baseline (Baseline Psychosis) and at first follow-up around 1 year post-baseline (T1). They were again interviewed by trained psychologists for the presence of psychotic symptoms at the second follow-up on average 3·5 years post-baseline (T2).

Results. The rate of T2 psychotic symptoms was 14·2% in those exposed to neither Baseline Psychosis nor Urbanicity, 12·1% in those exposed to Urbanicity alone, 14·9% in those exposed to Baseline Psychosis alone and 29·0% in those exposed to both Baseline Psychosis and Urbanicity. The odds ratio (OR) for the combined exposure was 2·46 [95% confidence interval (CI) 1·46–4·14], significantly greater than that expected if Urbanicity and Baseline Psychosis acted independently.

Conclusion. These findings support the suggestion that the outcome of the developmental expression of psychosis is worse in urban environments. The environment may impact on risk for psychotic disorder by causing an abnormal persistence of a developmentally common expression of psychotic experiences.

Background. Higher levels of religious involvement are modestly associated with better health, after taking account of other influences, such as age, sex and social support. However, little account is taken of spiritual beliefs that are not tied to personal or public religious practice. Our objective was to develop a standardized measure of spirituality for use in clinical research.

Method. We characterized the core components of spirituality using narrative data from a purposive sample of people, some of whom were near the end of their lives. These data were developed into statements in a scale to measure strength of spiritual beliefs and its reliability, validity and factor structure were evaluated in order to reach a final version.

Results. Thirty-nine people took part in the qualitative study to define the nature of spirituality in their lives. These data were used to construct a 47-item instrument that was evaluated in 372 people recruited in medical and non-medical settings. Analysis of these statements led to a 24-item version that was evaluated in a further sample of 284 people recruited in similar settings. The final 20-item questionnaire performed with high test–retest and internal reliability and measures spirituality across a broad religious and non-religious perspective.

Conclusions. A measure of spiritual belief that is not limited to religious thought, may contribute to research in psychiatry and medicine.