Numerous studies have reported high rates of psychosis in the Black Caribbean population in the UK. Recent speculation about the reasons for these high rates has focused on social factors. However, there have been few empirical studies. We sought to compare the prevalence of specific indicators of social disadvantage and isolation, and variations by ethnicity, in subjects with a first episode of psychosis and a series of healthy controls.

All cases with a first episode of psychosis who made contact with psychiatric services in defined catchment areas in London and Nottingham, UK and a series of community controls were recruited over a 3-year period. Data relating to clinical and social variables were collected from cases and controls.

On all indicators, cases were more socially disadvantaged and isolated than controls, after controlling for potential confounders. These associations held when the sample was restricted to those with an affective diagnosis and to those with a short prodrome and short duration of untreated psychosis. There was a clear linear relationship between concentrated disadvantage and odds of psychosis. Similar patterns were evident in the two main ethnic groups, White British and Black Caribbean. However, indicators of social disadvantage and isolation were more common in Black Caribbean subjects than White British subjects.

We found strong associations between indicators of disadvantage and psychosis. If these variables index exposure to factors that increase risk of psychosis, their greater prevalence in the Black Caribbean population may contribute to the reported high rates of psychosis in this population.

Whether alexithymia is a personality trait that increases the risk of major depression (MD) is still debated. In this prospective study, alexithymic levels were evaluated before, during and after a depressive episode.

The alexithymic levels, the presence of MD and the severity of anxious-depressive symptoms were evaluated at intervals of about 1 month in pregnant women attending the Centers for Prenatal Care, using the Toronto Alexithymia Scale (TAS), the Primary Care Evaluation of Mental Disorders (PRIME-MD) and the Hospital Anxiety and Depression Scale (HADS).

Sixteen women affected by MD, 21 affected by subthreshold depression and 112 non-depressed women were included in the study. Women who developed depression, compared to non-depressed women, showed similar TAS and HADS scores during the pre-morbid phase, a significant increase in the scores during depression and a significant decrease after remission, whereas no change was observed in non-depressed women.

Our data suggest that in pregnant women alexithymia does not represent a personality trait that increases the risk of developing a depressive episode, and they support the hypothesis that alexithymia is a state-dependent phenomenon in depressed pregnant women.

To date, there has been no large-scale survey of geriatric depression (GD) involving both rural and urban areas in China using standardized assessment tools and diagnostic criteria. This study aimed to determine the 12-month and lifetime prevalence rates of GD and sociodemographic correlates in urban and rural regions of Beijing, China.

A total of 1601 elderly patients (aged ⩾60 years) were randomly selected and interviewed in Beijing using the Composite International Diagnostic Interview (CIDI 1.0). Basic sociodemographic and clinical data were also collected during the interviews.

The overall 12-month prevalence of GD was 4.33%, and the 12-month prevalence rates for men and women were 2.65% and 5.83% respectively. The overall lifetime prevalence of GD was 7.83%, and lifetime prevalence rates for men and women were 4.65% and 10.66% respectively. Female sex, lower educational level, monthly income, rural abode, and the presence of one or more major medical conditions were associated with increased risk of GD. Of the GD subjects interviewed, 25.2% were receiving some type of treatment, with only 4.7% preferring to seek treatment from mental health professionals.

Although still relatively low by international standards, there is an increasing trend in the prevalence of GD in China. The low percentage of subjects treated for GD is a major public health concern that should be addressed urgently.

Resemblance between spouses can be due to phenotypic assortment, social homogamy and/or marital interaction. A significant degree of assortment can have consequences for the genetic architecture of a population. We examined the existence and cause(s) of assortment for obsessive–compulsive (OC), anxious and depressive symptoms in a population-based twin-family sample.

OC, anxious and depressive symptoms were measured in around 1400 twin–spouse pairs and >850 parent pairs. Correlations of twins and their spouse, twin and co-twin's spouse, spouses of both twins and parents of twins were obtained to consider phenotypic assortment versus social homogamy as possible causes of marital resemblance. The association of length of relationship with marital resemblance was also investigated. Finally, we examined whether within-trait or cross-trait processes play a primarily role in marital resemblance.

Small but significant within-trait correlations of between 0.1 and 0.2 were seen for spouse similarity in OC, anxious and depressive symptoms. Cross-correlations were significant but lower. There was no correlation between length of relationship and marital resemblance. From the pattern of correlations for twin–spouse, co-twin–spouse and spouses of both twins, phenotypic assortment could not be distinguished from social homogamy. Both within- and cross-assortment processes play a role in marital resemblance.

Small within- and across-trait correlations exist for OC, anxious and depressive symptoms. No evidence for marital interaction was found. Spouse correlations are small, which makes it difficult to distinguish between social homogamy and phenotypic assortment. It is unlikely that correlations of this size will have a large impact on genetic studies.

Attentional difficulties reported in individuals with anorexia nervosa (AN) may be due to preferential processing of disease-salient stimuli at a pre-attentive or at a conscious level or to a general problem in attention. Attentional difficulties may be associated with duration of illness.

Female participants with AN (restricting subtype; n=24) and healthy comparison women (n=24) were randomly allocated to subliminal or supraliminal exposure to visual stimuli (food, neutral and aversive images) while performing the 1-back and 2-back working-memory tasks.

Participants with AN made fewer errors than the healthy comparison group in the subliminal condition but significantly more errors in the supraliminal condition [condition×group interaction, F(1, 44)=6.82, p<0.01]: this was irrespective of stimulus type (food, neutral and aversive) and task (1-back or 2-back). The total number of errors made correlated positively with the duration of the AN for both the 1-back task (rs=0.46, p<0.05) and for the 2-back task (rs=0.53, p<0.01).

Decreased ability to concentrate in the presence of explicit distracters is a feature of AN and is associated with longer duration of illness. This phenomenon could be addressed in psychological interventions.

Significant associations between changes in ovarian hormones and binge eating are present across the menstrual cycle in women with bulimia nervosa. However, no study has examined these relationships in a non-clinical sample, despite the need for these data for designing risk-factor studies.

In study 1, we modified several continuous measures of binge eating and identified those that were most sensitive to menstrual-cycle fluctuations in a non-clinical sample of 10 women who completed measures for 35 days. In study 2, we explored associations between ovarian hormones and binge-eating scores in nine women who completed these same measures for 65 days and provided daily saliva samples for assays of estradiol and progesterone concentrations.

In study 1, the Emotional Eating subscale of the Dutch Eating Behavior Questionnaire exhibited superior reliability and was most sensitive to predicted menstrual-cycle changes in binge eating (i.e. increased scores in the mid-luteal/premenstrual compared with follicular/ovulatory phases). In study 2, this scale showed predicted inverse associations with estradiol and positive associations with progesterone across the menstrual cycle that could not be accounted for by changes in negative affect.

Associations between ovarian hormones and binge eating are robust and present in clinical and non-clinical samples. Findings support the ability to examine the role of ovarian hormones as risk factors for binge eating in large-scale prospective studies and twin studies.

Common fears change over development. Genetic and environmental risk factors for fears are partly shared across fears and partly fear-specific. The nature of the changes in common and fear-specific genetic and environmental risk factors over time is unknown.

Self-reported fears were obtained at ages 13–14, 16–17 and 19–20 from 2404 twins in the Swedish Twin Study of Child and Adolescent Development. A multivariate longitudinal twin analysis was conducted with Mx.

Eighteen individual items formed four fear factors: animal, blood-injury, situational, and social. The best-fit model had no quantitative or qualitative sex effects or shared environmental effects, but included a strong common factor with a stable cross-time structure with highest loadings on situational and lowest loadings on social fears. New common and fear-specific genetic risk factors emerged over development. With increasing age, genetic effects declined in overall importance and became more fear-specific. Cross-time continuity in specific genetic effects was highest for animal and lowest for social fears. Social fears had a ‘burst’ of specific genetic effects in late adolescence. Individual-specific environmental factors impacted both on the general fear factor and on specific fears. Compared to genetic effects, the impact of the unique environment was more time-specific.

Genetic and environmental risk factors for individual fears are partly mediated through a common fear factor and are partly fear-specific in their effect. The developmental pattern of these risk factors is complex and dynamic with new common and specific genetic effects arising in late adolescence and early adulthood.

Dissociative reactions in post-traumatic stress disorder (PTSD) have been regarded as strategic responses that limit arousal. Neuroimaging studies suggest distinct prefrontal responses in individuals displaying dissociative and hyperarousal responses to threat in PTSD. Increased prefrontal activity may reflect enhanced regulation of limbic arousal networks in dissociation. If dissociation is a higher-order regulatory response to threat, there may be differential responses to conscious and automatic processing of threat stimuli. This study addresses this question by examining the impact of dissociation on fear processing at different levels of awareness.

Functional magnetic resonance imaging (fMRI) with a 1.5-T scanner was used to examine activation to fearful (versus neutral) facial expressions during consciously attended and non-conscious (using backward masking) conditions in 23 individuals with PTSD. Activation in 11 individuals displaying non-dissociative reactions was compared to activation in 12 displaying dissociative reactions to consciously and non-consciously perceived fear stimuli.

Dissociative PTSD was associated with enhanced activation in the ventral prefrontal cortex for conscious fear, and in the bilateral amygdala, insula and left thalamus for non-conscious fear compared to non-dissociative PTSD. Comparatively reduced activation in the dissociative group was apparent in dorsomedial prefrontal regions for conscious fear faces.

These findings confirm our hypotheses of enhanced prefrontal activity to conscious fear and enhanced activity in limbic networks to non-conscious fear in dissociative PTSD. This supports the theory that dissociation is a regulatory strategy invoked to cope with extreme arousal in PTSD, but this strategy appears to function only during conscious processing of threat.

Hypersensitivity to electromagnetic fields (EMF) is frequently claimed to be linked to a variety of non-specific somatic and neuropsychological complaints. Whereas provocation studies often failed to demonstrate a causal relationship between EMF exposure and symptom formation, recent studies point to a complex interplay of neurophysiological and cognitive alterations contributing to symptom manifestation in electromagnetic hypersensitive patients (EHS). However, these studies have examined only small sample sizes or have focused on selected aspects. Therefore this study examined in the largest sample of EHS EMF-specific cognitive correlates, discrimination ability and neurobiological parameters in order to get further insight into the pathophysiology of electromagnetic hypersensitivity.

In a case-control design 89 EHS and 107 age- and gender-matched controls were included in the study. Health status and EMF-specific cognitions were evaluated using standardized questionnaires. Perception thresholds following single transcranial magnetic stimulation (TMS) pulses to the dorsolateral prefrontal cortex were determined using a standardized blinded measurement protocol. Cortical excitability parameters were measured by TMS.

Discrimination ability was significantly reduced in EHS (only 40% of the EHS but 60% of the controls felt no sensation under sham stimulation during the complete series), whereas the perception thresholds for real magnetic pulses were comparable in both groups (median 21% versus 24% of maximum pulse intensity). Intra-cortical facilitation was decreased in younger and increased in older EHS. In addition, typical EMF-related cognitions (aspects of rumination, symptom intolerance, vulnerability and stabilizing self-esteem) specifically differentiated EHS from their controls.

These results demonstrate significant cognitive and neurobiological alterations pointing to a higher genuine individual vulnerability of electromagnetic hypersensitive patients.

There is increased interest in assessing the family history of psychiatric disorders for both genetic research and public health screening. It is unclear how best to combine family history reports into an overall score. We compare the predictive validity of different family history scores.

Probands from the Dunedin Study (n=981, 51% male) had their family history assessed for nine different conditions. We computed four family history scores for each disorder: (1) a simple dichotomous categorization of whether or not probands had any disordered first-degree relatives; (2) the observed number of disordered first-degree relatives; (3) the proportion of first-degree relatives who are disordered; and (4) Reed's score, which expressed the observed number of disordered first-degree relatives in terms of the number expected given the age and sex of each relative. We compared the strength of association between each family history score and probands' disorder outcome.

Each score produced significant family history associations for all disorders. The scores that took account of the number of disordered relatives within families (i.e. the observed, proportion, and Reed's scores) produced significantly stronger associations than the dichotomous score for conduct disorder, alcohol dependence and smoking. Taking account of family size (i.e. using the proportion or Reed's score) produced stronger family history associations depending on the prevalence of the disorder among family members.

Dichotomous family history scores can be improved upon by considering the number of disordered relatives in a family and the population prevalence of the disorder.

Inter-country adoptees run risks of developmental and health-related problems. Cognitive ability is one important indicator of adoptees' development, both as an outcome measure itself and as a potential mediator between early adversities and ill-health. The aim of this study was to analyse relations between proxies for adoption-related circumstances and cognitive development.

Results from global and verbal scores of cognitive tests at military conscription (mandatory for all Swedish men during these years) were compared between three groups (born 1968–1976): 746 adoptees born in South Korea, 1548 adoptees born in other non-Western countries and 330 986 non-adopted comparisons in the same birth cohort. Information about age at adoption and parental education was collected from Swedish national registers.

South Korean adoptees had higher global and verbal test scores compared to adoptees from other non-European donor countries. Adoptees adopted after age 4 years had lower test scores if they were not of Korean ethnicity, while age did not influence test scores in South Koreans or those adopted from other non-European countries before the age of 4 years. Parental education had minor effects on the test performance of the adoptees – statistically significant only for non-Korean adoptees' verbal test scores – but was prominently influential for non-adoptees.

Negative pre-adoption circumstances may have persistent influences on cognitive development. The prognosis from a cognitive perspective may still be good regardless of age at adoption if the quality of care before adoption has been ‘good enough’ and the adoption selection mechanisms do not reflect an overrepresentation of risk factors – both requirements probably fulfilled in South Korea.