Schizophrenia, Classification and Pathogenesis


Dr Gregor Kowal
Senior Consultant in Psychiatry and Psychotherapy,             German Board Certified,       Medical Director,                   Clinic for Health and Medical Care
Phone: 00971-4-4574240

Schizophrenia is a severe mental disorder, characterized by profound disruptions in thinking, affecting language, perception, and the sense of self. It often includes psychotic experiences, such as hearing voices or delusions. It affects people from all walks of life, and usually strikes young people (both men and women equally) between the ages of 15 and 30.

The word “schizophrenia” comes from the Greek roots “schizo” = split and “phrene” = mind to describe the fragmented thinking of people with the disorder and was introduced by Eugen Bleuler, a Swiss Psychiatrist. Despite the etymology of the term, schizophrenia does not imply a “split mind” and it is not the same as dissociative identity disorder – also known as “multiple personality disorder” or “split personality” – a very rare condition with which it is often confused in public perception.

Signs and symptoms:

The medical profession characterizes the symptoms of schizophrenia as “positive” or “negative”. Symptoms brought on by the illness (e.g. hallucination, delusions) are referred to as “positive”. Qualities taken away by the illness (e.g. one`s drive and motivation are gone) are called “negative”; this may also be caused by medication itself. In the major cases the patient does not accept that he is ill (denial). He may refuse to seek or cooperate with professional treatment or help from others.

Symptoms may include the following:

– Disordered or jumbled thinking: People with schizophrenia may have trouble getting their thoughts straight. This often means that a person says things which don’t make sense to others. – False beliefs which can’t be shaken: the person may believe that others are trying to harm him (paranoia: false beliefs of persecution), that he has strange powers, that others can hear his thoughts or that the TV or radio is sending him special messages. A person diagnosed with schizophrenia may experience hallucinations (most reported are hearing voices), delusions (often bizarre or persecutory in nature), and disorganized thinking and speech. The latter may range from loss of train of thought, to sentences only loosely connected in meaning, to incoherence known as word salad in severe cases.

– Altered sense of self: The person has strange perception of his body; he may feel his arms and legs or other parts of his body do not belong to him or are altered. Sometimes he feels of being bodiless, non-existent as a person. He finds it difficult to distinguish between where his body stops and the rest of the world begins.

– Changes in emotions: Emotions may be dulled or flat, or out of control and over-excited. Flattened emotions may result in a lack of facial expression and an appearance what is going on. Emotions may also be of place, for example, crying at something funny.

– Loss of purpose: The person may feel drained of energy and drive. He may lose interest in life. The illness may also cause him to neglect his health and personal hygiene.

– Social withdrawal: The person may retreat to a world of his own and avoid the company of others.

Most people with schizophrenia do not have all these symptoms. Some are more severely affected by them than others.


No-one knows yet what causes schizophrenia. Genetics, early environment, neurobiology, and psychological and social processes appear to be important contributory factors. Vulnerability to schizophrenia is partly inherited. The illness is more likely to occur in those with a schizophrenic first degree relative in the general population. Nevertheless, the majority of individuals with a close blood relative with schizophrenia do not developed the illness themselves. And schizophrenia commonly occurs in families where no-one is known to have had the illness before.

Current research is focused on the role of neurobiology. There are billions of nerve cells in the brain. Each nerve cell has branches which transmits and receive messages from other nerve cells. The branches release chemicals, called neurotransmitters, which carry the message from the end of one nerve branch to the end of another. In the brain afflicted with schizophrenia, something goes wrong in this communication system.

The evidence that schizophrenia is a biologically-based disease of the brain has accumulated rapidly during the past two decades. Recently this evidence has been also been supported with dynamic brain imaging systems that show very precisely the wave of tissue destruction that takes place in the brain that is suffering from schizophrenia.


Since Bleuler`s time, the definition of schizophrenia has continued to change, as scientists attempt to more accurately delineate the different types of mental diseases. Without knowing the exact causes of these diseases, scientists can only base their classifications on the observation that some symptoms tend to occur together. These classifications, while still employed in ICD 10 and DSM-IV, have not shown to be helpful in predicting outcome of the disorder, and the types are not reliably diagnosed.

The classification in accordance to ICD 10, a diagnostic system of World Health Organization (WHO) distinguished following types of schizophrenia:

Paranoid Schizophrenia: is the commonest type of schizophrenia in most parts of the world. The clinical picture is dominated by relatively stable, often paranoid, delusions, usually accompanied by hallucinations, particularly of the auditory variety, and perceptual disturbances.

Hebephrenic Schizophrenia: a form of schizophrenia in which affective changes are prominent, delusions and hallucinations fleeting and fragmentary, behaviour irresponsible and unpredictable, and mannerisms common. The mood is shallow and inappropriate and often accompanied by giggling or self-absorbed smiling, or by a lofty manner, grimaces, mannerisms, pranks, hypochondriacal complaints, and reiterated phrases. Thought is disorganized and speech rambling and incoherent. There is a tendency to remain solitary, and behaviour seems empty of purpose and feeling. This form of schizophrenia usually starts between the ages of 15 and 25 years and tends to have a poor prognosis because of the rapid development of “negative” symptoms, particularly flattening of affect and loss of volition.

Catatonic Schizophrenia: prominent psychomotor disturbances are essential and dominant features and may alternate between extremes such as hyperkinesis and stupor, or automatic obedience and negativism. Constrained attitudes and postures may be maintained for long periods. Episodes of violent excitement may be a striking feature of the condition. For reasons that are poorly understood, catatonic schizophrenia is now rarely seen in industrial countries, though it remains common elsewhere. These catatonic phenomena may be combined with a dream-like (oneiroid) state with vivid scenic hallucinations.

Simple Schizophrenia (schizophrenia simplex): an uncommon disorder in which there is an insidious but progressive development of oddities of conduct, inability to meet the demands of society, and decline in total performance. Delusions and hallucinations are not evident, and the disorder is less obviously psychotic than the hebephrenic, paranoid, and catatonic subtypes of schizophrenia. The characteristic “negative” features of residual schizophrenia (e.g. blunting of affect, loss of volition) develop without being preceded by any overt psychotic symptoms. With increasing social impoverishment, vagrancy may ensue and the individual may then become self-absorbed, idle, and aimless.

Residual Schizophrenia: a chronic stage in the development of a schizophrenic disorder in which there has been a clear progression from an early stage (comprising one or more episodes with psychotic symptoms meeting the general criteria for schizophrenia described above) to a later stage characterized by long-term “negative” symptoms.


Schizophrenia is generally believed to have accompanied mankind through its history. Ethnographic studies have demonstrated that schizophrenia is present in all existing cultures, from the pre-literate to the most highly advanced. Psychotic symptoms and schizophrenic-like syndromes were clearly present in ancient civilizations. Recorded descriptions of the disorder appeared before 1500 BC in the ancient Egyptian Book of Hearts, which is part of the Ebers papyrus.

Demonic or supernatural possession was often implicated as the cause of psychotic behaviours. The universal prevalence of these symptoms attests to the robust longevity of this frequently devastating disorder.

Although theories of demonic influences also held sway in Greek conceptions of madness, rationalist theories began to take hold. Plato, writing in the 5th and 4th centuries BC, advocated a very modern integrative conceptualization of the relationship between the mind and body. In the Dialogues he wrote that “…to think about curing the head alone, and not the rest of the body also, is the height of folly….And therefore if the head and body are to be well, you must begin by curing the soul.”

The Greek physician Hippocrates, widely considered the father of modern medicine, built upon the Greek tradition of rational and empirical explanations of nature and behaviour. He dismissed the idea of demonic causation of psychosis and instead suggested that madness originated entirely from the brain. In The “Holy Disease” he contended that “…only from the brain spring our pleasures, our feelings of happiness, laughter and jokes, our pain, our sorrows and tears…. This same organ makes us mad or confused, inspires us with fear and anxiety….” In order to explain the presence of various mental and physical disturbances, he postulated the existence of body “humors”. Optimal mental and physical functioning could only be achieved if these humors were in balance and harmony. An uneven distribution of these fundamental elements might result in madness.

One of the first to classify the mental disorders into different categories was the German physician, Emil Kraeplin. He used the term “dementia praecox” for individuals who had symptoms that we now associate with schizophrenia. He was the first to make a distinction in the psychotic disorders between what he called dementia praecox and manic depression. Kraepelin believed that dementia praecox was primarily a disease of the brain, and particularly a form of dementia. Kraepelin named the disorder `dementia praecox` (early dementia) to distinguish it from other forms of dementia (such as Alzheimer`s disease) which typically occur late in life

The word “schizophrenia” is less than 100 years old. The Swiss psychiatrist, Eugen Bleuler (1857-1939), coined the term, “schizophrenia” in 1911. He was also the first to describe the symptoms as “positive” or “negative.” Bleuler changed the name to schizophrenia as it was obvious that Krapelin`s name – dementia praecox – was misleading as the illness was not a dementia (it did not always lead to mental deterioration) and could sometimes occur late as well as early in life.

Schizophrenia in facts:

– Schizophrenia affects about 24 million people worldwide
– It is a treatable disorder. There are effective interventions (pharmacological and psychosocial) available.
– The earlier the treatment is initiated, the more effective it will be.
– More than 50% of persons with schizophrenia are not receiving appropriate care
– 90% of people with untreated schizophrenia are in developing countries
– Care of persons with schizophrenia can be provided at community level, with active family and community involvement

To achieve the best results in treatment of schizophrenia is to provide care to the patients through:
– appropriate training of the primary health care personnel
– provision of essential drugs
– strengthening of the families for home care
– referral support from mental health professionals and
– public education to decrease stigma and discrimination.

Famous people who have been diagnosed with schizophrenia:

A recent Nobel Laureate in Economics, John Forbes Nash Jr., has a lifetime history of Schizophrenia but is now doing very well, as has been well documented in the book “A Beautiful Mind” and the academy award-winning movie of the same name.

Following is a list of other famous people who have been diagnosed with schizophrenia, or who had suffered from schizophrenia:
– Albert Einstein`s son – Eduard Einstein
– Dr. James Watson`s son (Dr. Watson is co-discover of DNA and Nobel Prize winner)
– Peter Green, Guitarist for the band Fleetwood Mac
– Syd Barrett of the band Pink Floyd
– Mary Todd Lincoln, wife of Abraham Lincoln (past-President of the United States)


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