A number of factors have been proposed as being linked to schizophrenia: genetic, psychological, endocrinological, metabolic, environmental, virological, and auto-immunological factors, as well as neurotransmitter systems and structural disorders of the brain. All may act as predisposing, triggering, or functionally modulating factors in what is probably a condition composed of several types of disorder with varying aetiology. Neuroanatomical and neuromorphological data have revealed ventricular enlargement and diminished frontal and temporal lobe volume in some patients. These changes are concentrated particularly in the hippocampus/parahippocampal gyrus/amygdala, but are relatively small and span some overlap with healthy subjects. Twin studies suggest that at least some of these changes may result from other than genetic factors. Functional disturbances of the brain have also been connected with frontal and temporal structures in some schizophrenic patients. Of the single neurotransmitter substances, dopamine and serotonin appear to represent some of the central restitutive mechanisms whose function is to maintain mental stability; the understanding of their interplay with other neurotransmitters such as noradrenaline, acetylcholine, GABA, and glutamate, should provide a more integrated view of both normal and disturbed brain function.

The excess of winter–spring births among individuals suffering from schizophrenia provides strong evidence for the existence of some prenatally occurring factors in the pathogenesis of schizophrenia. Recent epidemiological findings suggest that maternal viral infections during the second trimester of pregnancy may play a crucial role in the aetiology of adult schizophrenia. A ‘two-hit window’ hypothesis of the mechanism of action of prenatal factors in the pathogenesis of schizophrenia suggests at least two time-specific prenatal aetiological events. The observed association between prenatal viral infection and increased incidence of adult schizophrenia need not be a direct cytotoxic result of the viral infection, but may be caused indirectly, for example from foetal minor cerebral haemorrhages produced by the anticoagulant effects of aspirin.

A nationwide Finnish sample of schizophrenics' offspring given up for adoption was compared blindly with matched controls, who were adopted offspring of non-schizophrenic biological parents. The adoptive families were investigated thoroughly using joint and individual interviews and psychological tests. The biological parents were also interviewed and tested. Among the 155 index offspring, the percentage of both psychoses and other severe diagnoses (borderline syndrome and severe personality disorders) was significantly higher than in the 186 matched control adoptees. This supports a genetic hypothesis. However, notable differences between these two groups only emerged in the families which were rated as disturbed. Thus the genetic effect (i.e. the differences between high and low genetic propensity) was only manifested as a psychiatric disorder in the presence of a disturbed family environment. The impact of disturbed family relations was strongest in the presence of the appropriate genotype.

Although the prevailing conception of the aetiopathogenesis of schizophrenia assumes the combined effect of a biological predisposition and of environmental stress, genetic factors have recently received more attention than environmental ones. Rather than concentrating on only one of these, Professor Tienari and his team have directed their research efforts to clarifying the joint effects of both. For that purpose, they have gathered a comprehensive body of material, starting from 19 447 schizophrenic women with 291 children given away for adoption; of the latter, 155 index children, with their biological and adoptive parents, were ultimately included in their study. A group of 185 control children was collected for comparison, and their parents (adoptive and biological) were also investigated.

For the investigation of the early course of schizophrenia starting from onset, the standardised Interview for the Retrospective Assessment of the Onset of Schizophrenia was developed and validated. In a representative sample of 267 first-admitted German schizophrenics of a broad diagnosis from a population of 1.5 million, the age at which different diagnostic and onset definitions were satisfied, the symptoms at the time of the interview, and the accumulation of positive and negative symptoms until first admission were assessed. Comparison between the two sexes and three age groups yielded hardly any differences in the accumulation of symptoms and their course until first admission, except for a slightly shorter period of negative symptoms in young males and a slightly longer one in older women – which contradicts prevailing opinion. At the time of the interview, no significant sex differences were found with respect to the core symptoms of schizophrenia (negative and first-rank symptoms), but clear and substantial differences emerged in disease behaviour. The significantly higher age at first onset in women is explained, on the basis of animal experiments and a clinical study, by the neuromodulatory effect of oestrogen on D2 receptors and by a higher vulnerability threshold in women.

It has long been thought that rates of mental illness are higher in cities than elsewhere, because of crowding and resultant stress. In the case of schizophrenia, there are some marked exceptions to generally higher prevalence rates in industrialised cities. Factors such as migration, culture, infectious disease, demographic rates, and other social processes may affect geographical differences in rates. The excess of schizophrenia in central city areas has been given two opposing explanations – the ‘breeder’ hypothesis and ‘social drift’. Data on incidence from three cities are compared, but do not reveal a clear common picture. Environmental factors connected with urban living are of two main types – social and non-social – which are not mutually exclusive; ‘urban’ may also have a variety of meanings. Rather than ‘urbanicity’ being an independent aetiological factor in schizophrenia, its effect may be largely explained in terms of migration and social class.

The integrative concept of ‘affect logic’ is based on a hypothesis concerning the laws of interaction between emotion and cognition. ”Affects“ are defined as global psychophysiological states which determine the prevailing functional ‘logic’, i.e. the specific ways in which cognitive elements are selected and linked together. This leads to an integrative psychosocio-biological evolutionary model of schizophrenia, in which a specific affective–cognitive vulnerability is built up in a first phase, through escalating interactions between unfavourable genetic–biological and psychosocial influences. In a second phase, the mental system is decompensated by psychosocial or biological stressors which induce psychosis. The great variability in long-term course (third phase) is conditioned by the complex interplay of many biological and psychosocial variables. The organising functions of affects are evident in schizophrenic core phenomena such as ambivalence, incoherence, and emotional flattening. This proposed model has numerous practical and theoretical implications.

Individual–psychological studies (psychoanalytical) and interactional studies (based on family research and family therapy) approach the psychological processes connected with the origins of schizophrenia from different angles. They thus complement each other. Five major propositions are formulated to integrate the psychodynamic concepts dealing with vulnerability to schizophrenia. The integration of family- and individual-centred starting-points has proved to be very useful in developing treatment methods for schizophrenic patients.

Since Gregory Bateson and his co-workers presented their double-blind theory of the aetiology of schizophrenia in the 1950s, no grand comprehensive theory of the disorder has appeared. The double-blind theory was never accepted by the worldwide psychiatric community, and empirical research during the 1970s gave no support to it. In recent years, psychiatrists have focused attention on limited aspects of the illness, and mini-theories have flourished, but this tendency has been typical for the social sciences in general. Therefore, it is refreshing to have two attempts to integrate biological, psychological, and social viewpoints. But have these succeeded?

Neuroleptic drugs have been used in the treatment of schizophrenic patients for 40 years. In the 1960s it was proposed that the mechanism of action was a blockade of dopamine receptors; in vivo studies give strong evidence that a blockade of D2 dopamine receptors mediate the antipsychotic effect of classic neuroleptics. However, the antipsychotic effect of neuroleptics is synergistic with family treatment and social-skills training.

As schizophrenia is a heterogeneous condition with a variety of possible causes, it is sensible to combine biological and social treatment. Neuroleptic drugs give partial protection against environmental stress, but need to be supplemented. The programme developed on the basis of research on relatives' expressed emotion begins with education about schizophrenia for patients and relatives. Family sessions in the home are run in parallel with a relatives' group, and are aimed at improving communication, teaching problem-solving skills, lowering criticism and overinvolvement, reducing social contact between patient and relatives, expanding social networks, and lowering expectations. Individual work with the patient is often undertaken alongside the family sessions, and includes social-skills training, anxiety management, and a cognitive approach to persistent psychotic symptoms. Therapists take a central role in coordinating the variety of services needed by patient and relatives.

People with schizophrenia lack the ability to develop – to differentiate and integrate – their self- and object-representations, and suffer from primitive ‘object-relations’ conflicts, which occur when they try to develop (to differentiate and integrate) their self- and object-world. When a therapist interacts beneficially with a schizophrenic patient and enables him/her to identify with the ego functions involved in this interaction, the patient's frail psychic structure receives nourishment that will strengthen it: this process is similar to human development, where a child attains psychic organisation by interacting with the one who nurtures him/her. The recommended approach in the psychoanalytic psychotherapy of schizophrenia is to ‘allow’ the natural evolution of the fusion–defusion and introjection–projection processes to appear in the experiences of transference and counter-transference.

The paper describes a study based on the Nordic multi-centre research project NIPS. In the Norwegian part, based on one-year screening and sampling of all new schizophrenic cases in a catchment area in Oslo, patients and therapists were interviewed after 2–3 years. Some patients seemed to have played a much more active part in establishing and breaking therapeutic contacts and in setting the terms for the relationship than is usually acknowledged. In the interviews at five-year follow-up, many patients produced viewpoints on their psychotherapeutic experiences that seem to be very important in relation to therapy.

Need-adapted treatment of schizophrenia is an integrative treatment model developed in the Turku Schizophrenia Project. It is based on the interactional viewpoint and understanding on the interactional level. Experience of family and network therapy has shown that immediate interactions-oriented intervention is an essential starting-point for the treatment. It creates the possibility for the treatment as a whole to become a therapeutic process. For clinical purposes, it has seemed logical to divide the patients into three groups; the methods and focus of the family-oriented work differ somewhat between the groups. The main separator between these is the level of social functioning before the psychosis.

The aim of the study reported here was to develop psychotherapeutic in-patient treatment for acute schizophrenia, following the principles of a need-adapted approach. To improve the integration of experiences which hospital staff have with acutely psychotic patients and their families, systematic supervision sessions were organised. In these sessions, it was possible to achieve shared psychological images through which the whole staff could integrate patients' behaviour and symptoms, both symbolic and non-symbolic. Such an image was called ‘the shared image guiding the treatment process’ (SIGTP). The process of achieving the SIGTP was interpreted through Peircean semiotics, especially the concepts of indexical, iconic, and symbolical signs. An SIGTP was considered to have been achieved in the early phase of the supervision process in 32 of the 54 cases. For the patients, SIGTP and the need-adaptation connected with it meant achieving a more realistic and more functional ordering of their experiences.

In the mental health field, the attention given to the subjective side of a person's experience is grossly inadequate. The best way to reflect the subjectivity of a person may be by means of the subjectivity of another. To take account of both subjective experience and objective measures in the course of mental disorders, a new concept is needed. This may be the person's story.

Schizophrenia constitutes a lifelong vulnerability in relation to life stresses and the maintenance of social networks. Satisfactory quality of life – understood as subjective well-being in a lifetime perspective – is the ultimate treatment objective. This paper draws on research and clinical experience from Lofoten – the catchment area of a psychiatric out-patient clinic in Northern Norway. This work stresses the quality of life for the social network around the psychiatric patient as a consideration in its own right. The patient's coping resources and social network are regarded as a continuous professional concern.