Clinical characteristics of Schizophrenia

Schizophrenia (sz) is a group of psychotic disorders that are characterised by a lack of contact with reality. Symptoms are mainly disturbances of thought processes but also of emotion and behaviour. 

There are also two major symptom categories: acute schizophrenia characterised by positive symptoms (hallucinations, delusioms) and chronic schizophrenia characterised by negative symptoms (apathy, withdrawal). These can also be categorised as a Functional Disorder and an Organic disorder, respectively. DSM-IV has moved away from these definitions and classified sz into three main sub-types: paranoid, disorganised and catatonic. 

Although it can emerge later in life, often suddenly, the onset for sz in men is usually in the late teens or early twenties and for women the onset is usually in the late twenties.

Around 1/3rd have a single episode or just a few brief, acute episodes and recover fully, while another 1/3rd have an episodic pattern of acute symptoms throughout life, maintaining a reasonable level of functioning whilst in remission. For the remaining 1/3rd there is an unremitting course which deteriorates from acute to chronic symptoms. Treatment can reduce the affects of acute symptoms and some people recover spontaneously but, as yet, there is no known cure for sz, despite the vast amount of money spent on research worldwide. 

These include thought insertion (the belief that thoughts are being inserted into the mind from the outside, under the control of external forces), thought withdrawal (the belief that thoughts are being removed from the mind) and thought broadcasting (the belief that thoughts are being made known to others).

External forces may be 'the Martians', 'the Communists', 'the Government' etc and the mechanism by which thoughts are affected is often a 'special ray' or a radio transmitter. 

Thought broadcasting is also an example of a delusion.

Hallucinations are perceptions of stimuli not actually present. They may occur via any of the senses, but the most common are auditory.Typically, voiced come from outside the individual's head and offer a 'running commentary' on behaviour in the third person e.g. 'he is now washing his hands, he will go and dry them. 

Sometimes they will comment on the individual's character, usually insultingly, or give commands but they may also be perceived as amusing and reassuring (Chadwick and Birchwood 1994)

Somatosensory hallucinations involve changes in how the body feels e.g. 'bumpy' or 'numb'.Depersonalisation, in which the person feels separated from the body. 

Hallucinations are often distortions of real environmental perceputal clues e.g. noises that come from a heating system are heard as whispering voices (Frude, 1998)

Delusions are false beliefs which persist even in the presence of disconfirming evidence:

• A delusion of grendeur is the belief that one is somebody who is or was important or powerful e.g. Jesus Christ, Napolean
• A delusion of persecution is the belief that one is being plotted or conspired against, or being interfered with by certain people or organised groups. 
• A delusion of reference is the belief that objects, events and so on have a (typically negative) personal significance. For example, a person may believe that the words of a song specifically refer to him/her. 
• A delusion of nihilism is the belief that nothing really exists and that all things are simply shadows. The belief that one has been dead for years and is observing the world from afar is also common. 

All delusions are held with extraordinary conviction, and the person may be so convinced of their truth that they are acted on, even if this involves murder. 

Although constantly bombarded by sensory informaton, we are usually able to sttend selectively to some and exclude the rest. This ability is impaired in people with sz, and leads to overwhelming and unintegrated ideas and sensations which affect concentration. Thus, people with sz are easily distracted. 

The classic disturbance in form of sz thoughts (as opposed to content) involves loose association (or derailment). The individual shifts from topic to topic as new associations arise, and fails to form coherent and logical thoughts. As a result, language is often rambling and disjointed. 

In some cases, thought process disorder is brief and intermitted. However, disturbances of affect (emtional disturbances), and other characteristic disturbances, tend to be fairly stable. The three main types of emotional disturbances are as follows:

• Blunted affect - An apparant lack of emotional sensitivity - the person responds impassively to events that would ordinarily evoke a strong emotional response
• Flattened effect - This is a more general absence of emotional expression, in which the person appears devoid of any sort of emotional tone. Flattened affect may reflect the sz's 'turning off' from stimuli they are incapable of dealing with, for self-protection. 
• Inappropriate effect - Display of emotion incongruous with context e.g. responding to bad news by uncontrolled giggling. 

In some szs, motor behaviour is affected. In catatonia, the individual assumes an unusual posture which is maintained for hours or days (catatonic stupor).

Attempts to alter the posture can be met with resistance and sometimes violence.

In stereotypy, the person engages in purposeless, repetitive movements, such as rocking back and forth or knitting an imaginary sweater.

Instead of being mute and unmoving, the individual may be wild and excited, showing frenetically high levels of motor activity (catatonic excitement).

This is withdrawal from interactions with other people. It sometimes involves living an asocial and secluded life, through loss of drive, interest in the environment etc. More disturbed individuals appear to be oblivious to others presence and completely unresponsive when people like friends and relatives attempt contact. 

Both ICD-10 and DSM-IV distinguish between different types of schizophrenia. This is because the disorder's characteristics are so variable. 

- Hebephrenic sz

- Simple sz

- Catatonic sz

- Paranoid sz

- Undifferentiated (atypical) sz

- Other

This is the most severe type, also known as disorganised sz.

It is most often diagnosed in adolescence and young adulthood, and is usually progressive and irreversible.

Its main characteristics are incoherent language, disorganised behaviour, delusions, vivid hallucinations (often sexual or religious) and loose associations.

It is also characterised by flattened or inappropriate affect, and extreme social withdrawal and impairment. 

Usually appears during late adolescence and has a slow, gradual onset. 

Principally, the individual withdraws from reality, has difficulty in making or keeping friends, is aimless and lack drive, and shows a decline in academic or occupational performance. Males often become drifters or tramps, whilst females may become prostitutes. 

Simple schizophrenia is only recognised by ICD-10 which, whilst acknowledging that it is controversial, retains it because some countries still use it. 

 Individuals may hold unusual and difficult positions until their limbs grow swollen, stiff and blue from lack of movement. An interesting feature is waxy flexibility, in which the individual maintains a position into which he or she has been manipulated into by others. 

Catatonic szs may engage in agitated catatonia: bouts of wild, excited movement, and may become dangerous and unpredictable.

In mutism, the person is apparently totally unresponsive to external stimuli. However, catatonic szs often are aware of what others were saying or doing during the catatonic episode, as evidenced by their reports after the episode has subsided.

Another characteristic is negativism, in which the individual sits either motionless and resistant to instruction, or does the opposite of what has been requested. 

This has the presence of well-organised, delusional thoughts as its dominant characteristic. 

Paranoid schizophrenics show the highest level of awareness, and least impairment, in the ability to carry out daily functions. 

Thus, language and behaviour appear relatively normal. However, the delusions are usually accompanied by hallucinations which are typically consistent with them. It tends to have a later onset than the other schizophrenias, and is the most homogenous type (paranoid szs are more alike than simple, catatonic and hebephrenic). 

This is a 'catch all' category for people who either fit the criteria for more than one type, or do not appear to be of any clear type. For example, disorders of thought, perception and emotion, without the features particular to the types desribed previously, would result in the label undifferentiated being applied. 

• Schizophreniform psychosis - similar to schizophrenia, but lasting for less than 6 months
• Schizotypal disorder - eccentirc behaviour and unusual thoughts and emotions resembilng those of schizophrenia, but without characteristis of schizophrenic abnormalities
• Schizoaffective disorder - episodes in which both schizophrenic and affective characteristics are prominent, but which do not justify a diagnosis of either schizophrenia or an affective disorder. 

The characteristics of schizophrenia rarely appear in 'full-blown' form. Typically, there are three phases in schizophrenia's development.

• The prodromal phase - usually occurs in early adolecence (process sz) or in relatively well-adjusted people in early adulthood (reactive sz). The individual become less interested in work, school, leisure activities and so on. Typically, he/she becomes increasinly withdrawn, eccentric and emotionally flat, cares little for health and appearance, and shows lowered productivity with either work or school. This phase may last from a few weeks to a few years. 
• The active phase - sz's main characteristics appear. In some people, this only lasts a few months, whereas in others it lasts a lifetime. If and when it subsides (usually after therapy), the person enters the residual phase. 
• The residual phase - characterised by the lessening of major characteristics and more-or-less return to the prodromal phase. Around 25% of szs regain capacity of function normally, 50-65% alternate between residual and active phases.