Background. Despite more than 100 years of study, there remains no definitive diagnostic validation of the functional psychoses. Factor analysis suggests the presence of three or more psychopathological syndromes in functional psychoses as a whole. The relationship between these factors and cerebral anatomy has been investigated in schizophrenia only. This study aimed to address the relationship of symptom factors to clinically important variables and cerebral anatomy in a sample of psychotic patients with a spread of diagnoses.

Methods. In a sample of patients with functional psychoses, symptom data was obtained on four consecutive admissions using the OPCRIT symptom checklist. OPCRIT data was used to generate operational diagnoses in accordance with pre-set criteria and a principle components analysis was performed on symptom data. Factor loadings were compared between each admission to examine factor stability over time. Factor scores at first admission were also correlated with clinical variables obtained from patients' case notes. From the sample of 204 patients, 64 subjects were recruited and underwent an MRI scan of the brain. Regional anatomical volumes were compared with diagnosis and factor loadings at first admission.

Results. A principal components analysis gave a four-factor solution of ‘manic’, ‘depressive’, ‘disorganization’ and ‘reality distortion’ factors at each admission. Factors showed a high degree of stability over the four admissions studied. The factors were significantly associated with several clinical variables. Three of the four factors were associated with a specific pattern of cerebral anatomy.

Conclusions. This study suggests that factors may correspond to relatively specific disease processes underlying functional psychotic illness. We propose that the use of symptom factors may facilitate the investigation of the underlying mechanisms of psychotic illness.

Background. The aim of this study was to assess visual information processing and cognitive functions in unaffected siblings of patients with schizophrenia, bipolar disorder and control subjects with a negative family history.

Methods. The siblings of patients with schizophrenia (N = 25), bipolar disorder (N = 20) and the controls subjects (N = 20) were matched for age, education, IQ, and psychosocial functioning, as indexed by the Global Assessment of Functioning scale. Visual information processing was measured using two visual backward masking (VBM) tests (target location and target identification). The evaluation of higher cognitive functions included spatial and verbal working memory, Wisconsin Card Sorting Test, letter fluency, short/long delay verbal recall and recognition.

Results. The relatives of schizophrenia patients were impaired in the VBM procedure, more pronouncedly at short interstimulus intervals (14, 28, 42 ms) and in the target location task. Marked dysfunctions were also found in the spatial working memory task and in the long delay verbal recall test. In contrast, the siblings of patients with bipolar disorder exhibited spared performances with the exception of a deficit in the long delay recall task.

Conclusions. Dysfunctions of sensory-perceptual analysis (VBM) and working memory for spatial information distinguished the siblings of schizophrenia patients from the siblings of individuals with bipolar disorder. Verbal recall deficit was present in both groups, suggesting a common impairment of the fronto-hippocampal system.

Background. Twin studies have concluded that there is a substantial genetic contribution to the aetiology of eating disorders. The aim of the present study was to estimate the genetic contribution to the aetiology of self-reported eating disorders in a sample of representative twins.

Method. A population cohort of 34142 young Danish twins was screened for eating disorders by a mailed questionnaire.

Results. Concordance rates differed significantly across monozygotic and dizygotic twin pairs for broadly defined self-reported anorexia nervosa and bulimia nervosa. Heritability estimates of 0·48, 0·52 and 0·61 respectively were estimated for narrow and broad definitions of self-reported anorexia nervosa and for self-reported bulimia nervosa.

Conclusions. There is a genetic contribution to the aetiology of self-reported eating disorders in the general population. The relationship between self-reported and clinical eating disorder remains to be examined.

Background. The objective of the study was to develop the cognitive understanding of persecutory delusions. It was hypothesized that safety behaviours contribute to the persistence of persecutory delusions by preventing disconfirmation. It was further hypothesized that emotional distress is associated with aspects of the content of delusions. An investigation was designed to establish whether individuals with persecutory delusions use safety behaviours, and to test predicted associations between delusion content and emotional distress.

Method. A cross-sectional investigation was conducted on 25 individuals with persecutory delusions. A detailed assessment was made of the presence of safety behaviours, the content of delusions and emotional distress.

Results. All participants had used at least one safety behaviour in the last month, most typically avoidance. Higher levels of anxiety were associated with greater use of safety behaviours. New data were obtained on the content of persecutory delusions. Aspects of the content of the delusions were associated with levels of depression, self-esteem, anxiety and delusional distress.

Conclusions. Individuals with persecutory delusions use safety behaviours. The findings may develop the understanding of delusion persistence, acting upon delusions and the negative symptoms of schizophrenia. There are implications for cognitive interventions for psychosis. Support was also found for the hypothesis that emotional distress is linked to the content of delusional beliefs; it is speculated that prior emotional distress influences the content of delusions, and that delusion content in turn influences levels of emotional distress.

Background. Mental mechanisms have evolved to enable animals (and humans) to be able to function in various social roles. It is suggested that the nature and functions of the mental mechanisms that enable animals to act as a hostile–dominant or threatened–subordinate can be distinguished. It is further suggested these can be internally activated and ‘play off’ against each other, such that a person ‘attacks’ themselves and then responds to their own internal attacks with subordinate defences. Hence, a depressed person can submit, feel defeated, belittled, beaten down, or want to run away (escape) from their own self-attacking thoughts, while psychotic voice hearers can feel similarly to their hostile voices. Such internal interactions may relate to depression in both psychotic voice hearers and depressed people.

Method. A group of 66 voice hearers with a diagnosis of schizophrenia and 50 depressed patients were compared on a series of self-report questionnaires measuring the power of hostile self-directed thoughts/voices and the activation of defensive responses, especially fight/flight.

Results. We present evidence that schizophrenic, malevolent voice hearers and self-critical depressed people experience their hostile, internally generated voices/thoughts as powerful, dominating and controlling (i.e. have typical characteristics of a hostile dominant). Moreover, these voices/thoughts activate evolved subordinate defences such as fight/flight and these are associated with depression in both depression and schizophrenia.

Conclusion. Conceptualizing aspects of depressed and psychotic thinking as relating to evolved mental mechanisms, which are role serving, but can internally play off against each other, may open new ways of investigating certain aspects of severe pathologies.

Background. The present study examined biases in visual attention for emotional material in children and adolescents with post-traumatic stress disorder (PTSD) and healthy controls.

Methods. The participants carried out an attentional deployment task in which probe detection latency data were used to determine the distribution of visual attention for threat-related and depression-related material.

Results. The results showed that children and adolescents with PTSD, relative to controls, selectively allocated processing resources towards socially threatening stimuli and away from depression-related stimuli. This attentional avoidance of depression-related information in the PTSD participants declined with age.

Conclusions. The results of the study are interpreted as a consolidation and extension of previous research on attentional bias and emotional disorder in younger participants.

Background. Home and work factors have been linked to psychological status, but less is known about their contribution to social inequalities in psychological status. We examine whether social inequalities in psychological distress can be explained by work–home factors and whether the impact of these potential explanatory factors is similar for men and women.

Methods. Data are from the 1958 British birth cohort study. We sought to explain social class differences in psychological distress at age 33. Explanatory factors were classified as work–home roles: i.e. employment, marital status, domestic responsibility, children and elderly care; and work–home characteristics: i.e. job-strain, insecurity, unsocial working hours, youngest child's age, number of children and level of involvement in childcare.

Results. A social gradient in psychological distress was found: odds ratios for classes IV and V v. I and II were 2·65 (men) and 3·02 (women). Work factors had consistently stronger associations with psychological distress and with social class among men than women. Work factors had a greater impact on class differences in psychological distress in men. Associations for home roles and characteristics were less consistent and their combined effect on class differences in distress was negligible for both sexes.

Conclusion. Explanations for the social gradient differ for men and women. Work may be more important for men than women, but the impact of home factors was not strong during the early adulthood of this cohort.

Background. Much of the interest in hopelessness stems from the key role it plays in the prediction of suicidal behaviour. To measure hopelessness, Beck et al.(1974)developed a 20-item scale (BHS), applied exploratory factor analysis and argued that the scale measures three specific components (affective, motivational and cognitive). Subsequent exploratory factor analyses identified two, three or more factors underlying the scale.

Method. Several confirmatory factor analyses (LISREL) were run on data on 324 suicide attempters in Sweden in order to test the hypothesized factorial structures and to investigate the psychometric properties of the individual items.

Results. Neither three- nor two-factor models fitted the data. A simpler structure was sufficient to account for the observed correlations between most of the items. This led to the development of several variants of a one-factor model, each a combination of affective, motivational and cognitive items. The number of items varied between four and 15.

Conclusions. Our findings suggest that most of the items (15) of Beck's Hopelessness Scale measure one factor. They further suggest that the number of items could considerably be reduced. A four-item scale produced an excellent fit. It includes positive and negative items describing the perception of the future in terms of success, darkness, lack of opportunity and faith. It might even be possible to replace the total scale with one item only, ‘my future seems dark to me’.

Objective. Although family, twin and adoption studies have suggested that lifetime major depression (MD) is a heritable condition, nearly all these studies have relied for the diagnosis on long-term human memory, which is fallible and potentially biased. Could the estimates of heritability of MD be biased by the well-demonstrated genetic influences on memory?

Methods. Both members of 858 female–female twin pairs from a population-based registry were personally interviewed at least three times over 9 years. The interview assessed a history of depressive onsets and recoveries in the last year to the nearest month. We examine heritability of MD using four recall intervals: last year, last 6 months, last 3 months and current month.

Results. Examining the occurrence of one or more depressive episodes across all three interviews, heritabilities of MD (95% CI) for the four time periods were: 0·41 (0·27–0·54), 0·41 (0·26–0·55), 0·35 (0·16–0·52) and 0·34 (0·11–0·55). These heritability estimates did not differ significantly from one another. A similar pattern was found if heritability was assessed for the number of interviews in which criteria for MD were met.

Conclusion. Modelling results suggest that the heritability of MD was not influenced by the duration of the required recall. Genetic influences on human recall do not appear to contribute substantially to estimated heritability of MD.

Background. Neuroticism has been shown to increase the risk of depression whereas extraversion is associated with a reduction of risk. These personality traits play a central role in aetiological theories of affective disorder but their role in schizophrenia is unclear. In this study, the risk for schizophrenia associated with neuroticism and extraversion was examined and quantified.

Methods. Neuroticism and extraversion rated at the age of 16 years were examined in relation to adult schizophrenia in a national birth cohort of 5362 individuals.

Results. Neuroticism increased the risk of later schizophrenia independent of the level of affective symptoms in adult life (odds ratio over three levels: 1·93, 95% CI 1·09–3·43), whereas extraversion reduced the risk (OR: 0·44, 95% CI 0·23–0·84).

Conclusions. Depression and schizophrenia may share personality risk-increasing and risk-reducing factors. Coping styles associated with particular personality traits may determine whether isolated symptoms progress to full-blown illness.

Background. This study was undertaken to examine the relationship between anxiety co-morbidity and age of onset of panic disorder.

Methods. Age of onset of panic disorder and co-morbid anxiety disorders were assessed among 201 panic disorder probands with childhood separation anxiety disorder, obsessive–compulsive disorder, obsessive–compulsive symptoms, social phobia and specific phobia as part of a clinician-administered lifetime diagnostic interview. A generalized linear model was used to test the association between each anxiety co-morbidity and age of panic disorder onset while simultaneously controlling for the potential confounding effects of sociodemographic characteristics and other psychiatric co-morbidity.

Results. Earlier onset of panic disorder was found in patients with co-morbid obsessive–compulsive disorder, obsessive–compulsive symptoms and separation anxiety disorder, but not simple phobia or social phobia. Patients with both childhood separation anxiety disorder and obsessive–compulsive disorder had an even earlier panic onset than those with either childhood separation anxiety disorder or obsessive–compulsive disorder.

Conclusions. The association between anxiety co-morbidity and earlier onset of panic disorder is specific to obsessive–compulsive disorder and childhood separation anxiety disorder.

Background. Studies in the northern and southern hemispheres consistently identify seasonal patterns in suicidal deaths. In many such studies, bimodal yearly peaks have been described for females as against unimodal ones for males. The current study examines the monthly variation in suicidal deaths in Singapore to determine if any seasonal patterns exist in an equatorial region.

Methods. Monthly suicidal death data over the decade 1989–98 were examined for the whole sample and for gender- and age-specific subgroups. Both von Mises' distribution and harmonic analysis techniques were used to interpret the data.

Results. Among the 2013 male and 1382 female suicides, there was minimal variation in patterning of suicidal deaths. We found a weak suggestion of a later peak for the females in mid-May as opposed to mid-February for the males, and the peaks for those less than 25 years of age were 5–6 months later than for the older age groups. The magnitude of all peaks was, however, very small suggesting chance variation. The harmonic analyses confirmed that patterning was ‘randomly' rather than ‘seasonally' determined.

Conclusion. In an equatorial region, there was no evidence of any ‘seasonal' patterning of suicidal deaths.

Background. Genetic and environmental influences on broadly-defined anorexia nervosa (AN) syndrome were examined in a population-based twin sample.

Methods. AN syndrome was assessed in 672 female 17 year-old twins using structured interviews and a self-report questionnaire.

Results. Twenty-six probands with AN syndrome were identified. Biometrical model-fitting analyses indicated that genetic and non-shared environmental factors accounted for 74 % and 26 % of the variance in AN syndrome, respectively.

Conclusions. Findings support previous research indicating significant genetic and non-shared environmental influences on AN syndromes.

Background. Familial idiopathic basal ganglia calcification (FIBGC) is generally associated with neurological and psychiatric symptoms. An association between FIBGC and schizophrenia has been described but it remains uncertain. We studied the relationship between the presence and extent of basal ganglia calcification and schizophrenia in a multiply affected family.

Method. Symmetrical basal ganglia calcifications (BGC) were detected on computerized tomography (CT) in a schizophrenic proband and led us to carry out CTs and standardized psychiatric evaluations (SADS – Endicott & Spitzer, 1978) in all available first-degree relatives (mother and six siblings).

Results. Five subjects had BGC, including three subjects diagnosed as schizophrenic. Three subjects had no BGC and none of them was diagnosed as schizophrenic. We subdivided the BGC into three groups: massive (pallidum, striatum and dentate nuclei affected); medium (pallidum and striatum); and mild (pallidum only). The two subjects with massive BGC and one of the two with medium BGC had schizophrenia. The subject with mild BGC had no psychotic symptoms.

Conclusion. Our results are consistent with the hypothesis that BGC favours the occurrence of a schizophrenia-like syndrome and that the risk of occurrence of this syndrome is proportional to the extent of calcification. These findings support the hypothesis that schizophrenia is determined by a disruption of thalamo–cortico–striatal circuits.