Schizophrenia: overview, symptoms, causes, diagnosis, and treatment

The term schizophrenia is derived from the ancient Greek σχίζειν s'chizein = "to cleave, split, splinter" and φρήν phrēn = "spirit, soul, mind, diaphragm". In ancient Greece, the diaphragm was thought to be the seat of the soul, which is why the word "phren" (φρήν) stood for both terms. Until the middle of the 20th century, schizophrenia was literally translated as schizophrenia. This was intended to describe what was then regarded as the core of the illness: the "loss of the inner coherence of the processes of the soul".

The term was first introduced publicly by the Swiss psychiatrist Eugen Bleuler at a meeting of the German Psychiatric Association (DVP) in Berlin on April 24, 1908. Bleuler's colleague Carl Gustav Jung also used the term three days later on April 27 in Salzburg at the first International Psychoanalytic Congress (C.G. Jung was president of the congresses from 1910 to 1914). In the same year Bleuler published the article The Prognosis of Dementia praecox (Schizophrenia Group) in the Allgemeine Zeitschrift für Psychiatrie und psychischgerichtliche Medizin and in 1911 the well-known paper Dementia praecox or the Schizophrenia Group. Bleuler's concept of schizophrenia competed with Emil Kraepelin's concept of dementia praecox (premature dementia).

However, the first diagnoses with the designation "schizophrenia" were not made until 1921 and more frequently from 1930 onwards, at Burghölzli, (Eugen Bleuler had been director since 1898) for the first time in 1912.

In everyday clinical practice in psychiatric institutions, the term "Bleuler's disease" used to be used during ward rounds and in doctors' letters in order to avoid the negative and stigmatising term schizophrenia. In the past, schizophrenia and affective psychosis were combined under the term endogenous psychosis.

Schizophrenia is associated with limitations in some intellectual abilities, but not with reduced intelligence, although the historical term dementia praecox seems to reinforce this misconception. It is a matter of scientific debate whether schizophrenia is a single disease entity or a group of diseases - with different causes and courses.

Use of terms outside the technical language

Schizophrenia is often confused by medical laymen with identity disorders (dissociative identity disorder), especially with the idea of a "split personality". This is caused by a too literal back-translation of the two parts of the technical term, namely "split" and "mind".

In addition, since the 1950s, "schizophrenic" became established in colloquial language as a pejorative classification in the sense of "nonsensical, behaving absurdly, delusional, ambivalent". The general term mental illness was also formerly used for schizophrenia.

The symptoms of schizophrenia are traditionally divided into two broad areas: Positive symptoms and Negative symptoms. More recently, however, the cognitive symptoms of the disorder have also received increasing attention and are seen as a separate third domain.

Contrary to what the term suggests, however, it does not refer to intelligence deficits, but to problems with attention, memory, and action planning, among other things. The extent to which these areas are affected best predicts how well patients can cope with everyday life. Cognitive disturbances of this type are a central symptom complex of schizophrenia. Thinking may become short-tempered, or multi-layered relationships may not be grasped in their complexity. Linguistic expression becomes impoverished. In exacerbated cases, perseveration (stereotyped repetition of a word or thought) or idiolalia (unintelligible sounds) may occur.

The severity of symptoms depends in part on the personality of the individual. The overall symptomatology differs greatly between different individuals; however, individual patients often retain their individual symptom pattern over long periods of time.

Positive symptoms

Positive symptoms (or plus symptoms) denote exaggerations of normal experience and are therefore regarded as a kind of "surplus" compared to the healthy state. These include strong misconceptions of the experienced reality up to hallucinations and loss of reality. Schizophrenias with predominantly positive symptoms often begin suddenly, and often there are no outwardly conspicuous features beforehand. The course of the disease is rather favourable in this case.

Characteristic positive symptoms are content-related thought disorders, ego disorders, sensory delusions and inner restlessness. Typical for the content-related thought disorders is the formation of a delusion. Auditory hallucinations (acoasms) are common: About 84% of people with schizophrenic psychosis perceive thoughts that they think their origin is external. For example, they perceive voices that, in rare cases, also give orders. This is referred to in common parlance as "hearing voices". Often those affected have the impression of being insulted by foreign voices. Such an experience may occur while alone or in the midst of sentences said by bystanders. Hallucination of voices also occurs in deaf people, even in those born deaf. However, in deaf persons with a diagnosis of schizophrenia, visual and tactile hallucinations are significantly more common (in about 50% of persons each) than in schizophrenia in general (about 15% and 5%, respectively).

Ego disorders include:

• Ideation: experiencing one's own thoughts as imposed by others
• Thought propagation: the idea that others could "eavesdrop" or "read" one's own thoughts
• Thought deprivation: sense of loss that others are stealing or cutting off one's thoughts.
• External control: Feeling of being controlled by others like a remote-controlled robot.

Negative symptoms

Negative symptoms (or minus symptoms) refer to limitations of normal experience as well as of mental functions that were previously present but are reduced or completely absent due to the disease. These symptoms thus represent a deficiency compared to the healthy state. The following table gives an overview of the negative symptoms:

Schizophrenia with pronounced negative symptoms often begins insidiously, and the course of the disease is rather unfavorable. Negative symptoms can occur months or years before the acute psychotic symptoms ("bend in the life curve", "preceding defect"). Very often, sleep disturbances and not infrequently depressive symptoms occur as early symptoms. The negative symptoms usually intensify or solidify with increasing duration of the illness.

In about two thirds of people suffering from schizophrenia, the negative symptoms outlast the positive symptoms after an acute episode ("schizophrenic defect", "residual state", "residual symptomatology"). These limitations, which vary in severity, lead to contact disorder, social withdrawal, and often disability. However, in a certain percentage of people with schizophrenia, no residual symptoms remain (see residual symptomatology).

After the acute phase of a relapsing schizophrenia has subsided, a temporary depressive episode ("depressive aftershock") occasionally follows. A distinction should be made between true negative symptoms and the side effects of therapy with a neuroleptic. The side effects of neuroleptics can be similar to negative symptoms.