The use of the language of health and illness reflects the role doctors have played in offering care and treatment for psychological problems. In European and North American societies medical understandings, which draw on a range of scientific ideas, tend to be dominant and inform much lay discourse, especially about mental illness. However, in many contexts the term mental disorder, which has fewer medical connotations, is used. The impact of scientific ideas, as well as the ideas themselves, has varied historically and cross-culturally, and there have been times and places when the understandings have been magical or religious rather than scientific. Magical or religious ideas relating to mental illness have not entirely disappeared from lay understandings, such as when people think a mental or physical illness is a judgment of God or that health is a matter of luck and good fortune.

Modern-day medical ideas about mental illness have largely been developed in psychiatry, a medical specialty that emerged as a profession in the mid-nineteenth century from the associations of doctors working in charitable and public asylums that catered for “lunatics” and had powers of detention. In Europe a few institutions for lunatics were set up in the medieval period; these were followed first by small private madhouses in the sixteenth and seventeenth centuries and then, from the beginning of the nineteenth century, by charitable and public asylums. As the century progressed asylums became increasingly large-scale. They were mainly staffed by untrained attendants, with doctors usually the key figure of authority.

In the twentieth century asylum attendants were transformed into mental health nurses, and a range of other professionals (e.g., mental health social workers, psychotherapists, and clinical and health psychologists) started to contribute to the care and treatment of those with mental health problems and to understandings about mental health and illness. Mental health practice outside the asylum also expanded in the twentieth century. In the mid-twentieth century there was a move toward “communitycare,” which is the provision of services within community settings, even for those with more severe disorders, with far fewer mentally ill admitted to a psychiatric bed (where compulsory powers of detention are frequently used). The extent and quality of community services have often been questioned.

The types of mental illness identified by psychiatrists are diverse, ranging from the relatively severe and less common, such as schizophrenia, to the less severe and far more common, such as mild forms of depression and anxiety. Classifications have varied enormously over time, and during the second half of the twentieth century there were major attempts to systematize and standardize mental illnesses in order to improve the reliability of psychiatric diagnosis. In the twenty-first century two major classifications were developed: the American Diagnostic and Statistical Manual of Mental Disorders(DSM) and the listing of mental disorders in The International Classification of Diseases. The two classifications do not group mental disorders in the same way.

An earlier distinction widely used in the early postwar decades was between psychoses and neuroses, a contrast between more and less severe disorders that linked to symptom differences and ideas about causation. Psychoses were held to be primarily disorders of thought (i.e., Foucault’s unreason) and caused by biological factors. Psychoses were typified by the delusions and hallucinations of schizophrenia, the archetypical madness, associated with disturbed and sometimes difficult behavior. Bipolar disorder (formerly referred to as manic depression) is also placed in this category, as are usually disorders where there is clear brain pathology, such as the senile dementias. Neuroses, such as anxiety states and phobias, were considered primarily disorders of emotion (usually called “affect” or “mood” by psychiatrists) rather than thought and were held to have psychological causes. However, in its third edition in 1980, the DSM decided (not entirely successfully) to eschew etiology as a basis for classification shifting to a symptomatological categorization and excluding the term neurosis. Official classifications also include a range of conduct or personality disorders in which the main symptoms relate to behavior, such as “antisocial personality disorder,” anorexia nervosa, and substance use disorders, including alcoholism and drug addiction. Comparison of the different editions of the DSM is salutary. According to Allan V. Horwitz, the number of mental disorders listed in the 1918 edition of the DSM was 22, whereas by the fourth edition in 1995 it was nearly 400. Such increases necessarily broaden the boundaries of mental disorder and narrow those of mental health.

Consistent with medicine’s interest in the body, psychiatry has developed a “biomedical” model of mental illness. The biomedical model focuses on physical causes and the provision of physical treatments, although psychiatrists often deploy a wider range of understandings in their practice. The search for physical causes has concentrated on inheritance, brain pathology, and biochemistry. While there is strong evidence of a genetic tendency for more severe mental disorders, there can be no doubt that environmental Page 85 | Top of Articlefactors play a part in causation, even with severe disorders, and are important to mental health. For instance, the evidence from a range of studies has shown that genetic factors play a role in the etiology of schizophrenia, but there is also evidence of environmental factors having a role. Biochemical processes in the brain have been shown to underpin some mental illnesses, most obviously conditions such as Alzheimer’s disease. However, significantly data also indicate that social and behavioral factors, such as exercise (physical and mental) as well as diet and obesity, play a part in the complex etiology of Alzheimer’s disease.

Biochemical changes in the brain are associated with other mental disorders. There is evidence, for instance, that serotonin levels play a role in depression. But in contrast to Alzheimer’s, it is not clear that brain pathology is the cause of depression. The build up of serotonin may be a consequence of social and psychological experiences that are themselves better viewed as the cause of the depression. Such examples indicate that the causes of any mental illness are multifactorial and are not the same for one disorder as for another. They also indicate that debates about causation that have so vexed discussions of mental illness depend in part on the choice of which causes to examine. Psychiatrists have tended to focus on physical causes and to give them primacy, downplaying social and psychological factors.

Evidence of the importance of social and psychological factors to mental health comes from a range of studies. Many studies show that early childhood experiences affect mental health and that external stresses (stressful life events or ongoing difficulties, whether in childhood or later) can lead to mental disorder, although some would argue that in some disorders stress is more a precipitating factor than a cause. Data on the distribution of mental disorders across populations also display a marked social patterning. International studies show that a condition similar to schizophrenia is common across a wide range of societies. However, within any given society data indicate that schizophrenia is more common among groups with lower socioeconomic status and that this difference cannot be adequately accounted for by individuals with schizophrenia drifting down the socioeconomic scale. The link between socioeconomic status and mental illness applies to other disorders, such as depression. It has been argued that depression is due not only to the frequency of adverse life events but also to difficult circumstances and low levels of social support, which affect coping and its adverse vulnerability. There is also a marked patterning by gender. Whereas levels of schizophrenia are roughly the same for men and women, depression and anxiety are far more common in women than men, and personality and conduct disorders are more common in men. Part of this difference appears to be due to gender socialization and differing expectations as to appropriate emotions and behavior. There are also ethnic differences in the patterning of mental disorder. In the United Kingdom, for instance, a 1997 study by James Nazroo showed that schizophrenia is more commonly diagnosed in Afro-Caribbean men than in other social groups, though the reasons for this are not entirely clear.

Equally controversial have been related issues around the validity and boundaries of mental illness. A number of authors from different theoretical perspectives have argued that it is only reasonable to talk of illness when there is a clear physical pathology. For the psychiatrist Thomas Szasz, who famously argued in 1961 that mental illness was a myth, this meant recognizing that disorders such as senile dementia are diseases of the brain. Where there is no biological pathology, Szasz stated, psychological problems should be termed “problems in living” and not regarded as illnesses at all. From a rather different perspective, a range of sociologists has argued that mental illness, with its overtly behavioral symptoms, is best understood as a form of deviance (i.e., a behavior that breaks social norms) and not as illness. This position was developed by the psychotherapist T. J. Scheff in his well-known 1966 study Being Mentally Ill. These two positions reflect a long-standing contest between those who espouse the biomedical model of mental disorder and wish to appropriate psychological problems to the domain of physical illness—a process sociologists term medicalization and which is reflected in the expansion of psychiatric categories—and those who wish to appropriate mental disorder to the social (or psychological) domain of behavior considered unacceptable or difficult. Horwitz, in Creating Mental Illness, accepts that the boundaries of mental health and illness are set by society and tries to resolve the conflict between the two positions by stating that a condition is a valid mental illness or disorder if (a) it involves a psychological dysfunction that is defined as socially inappropriate, and (b) it is socially useful to define the dysfunction as a disease.

Psychological theories and therapies have, however, played an important role in ideas about mental health and the treatment of the less severe forms of mental illness. In the first half of the twentieth century psychoanalysis had a major impact, and “talking cures” began to be used by trained psychoanalysts, especially for private patients (in the United States psychoanalysis had widespread acceptance within psychiatry). Psychological theories also informed child and educational psychologyand the “mental hygiene” movement that flourished in the United States in the early decades of the twentieth century, in which the focus was on improving and sustaining mental health through education, early treatment, and public health.

However, some psychologists, highly critical of psychoanalysis, developed their own therapies based on the behaviorist ideas that swept academic psychology from the early decades of the twentieth century. Early behavior therapy excluded attention to thought and meaning but was gradually replaced by cognitive behavior therapy (CBT), which concentrates on the individual’s ways of thinking and is seen by some as offering a relatively speedy and effective route to mental health, especially for less severe disorders. CBT has been influenced by “positive psychology,” which is a set of ideas that seeks to encourage individuals to focus on what can give meaning in life, especially their strengths. Some also argue that CBT can be of value in treating psychosis. Yet psychological therapies such as physical remedies mainly concentrate on dealing with mental health problems that have already developed and not on mental health maintenance and prevention, the area to which social scientists have arguably more to contribute.