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Revision as of 00:16, 13 April 2005 by 68.79.113.16 (talk)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)Psychosis is a psychiatric classification for a mental state in which the perception of reality is distorted. Persons experiencing a psychotic episode may experience hallucinations (often auditory or visual hallucinations), hold paranoid or delusional beliefs, experience personality changes and exhibit disorganized thinking (see thought disorder). This is sometimes accompanied by features such as a lack of insight into the unusual or bizarre nature of their behavior, difficulties with social interaction and impairments in carrying out the activities of daily living.
Overview
Psychosis is usually considered by mainstream psychiatry to be a symptom of severe mental illness. Although it is not exclusively linked to any particular psychological or physical state, it is particularly associated with schizophrenia, bipolar disorder (manic depression) and severe clinical depression.
It is not uncommon in cases of brain injury and may occur after drug use, particularly after drug overdose or chronic use, although certain compounds may be more likely to induce psychosis, and some individuals may show greater sensitivity than others. The direct effects of hallucinogenic drugs are not usually classified as psychosis, as long as they abate when the drug is metabolised from the body.
Chronic psychological stress is also known to cause psychotic states, however the exact mechanism is uncertain. Psychosis triggered by stress in the absence of any other mental illness is known as brief reactive psychosis.
Psychosis is a descriptive term for a complex group of behaviours and experiences and as such is not a medical explanation in itself. Perhaps because of this, it is often confused with syndromes which may seem similar on the surface, or with words which may suggest, or seem to suggest a likeness.
The term psychosis should be distinguished from the concept of insanity, which is a legal term denoting that a person should not be criminally responsible for his actions. Similarly, it should be distinguished from psychopathy, a personality disorder often associated with violence, lack of empathy and socially manipulative behaviour. Despite the fact that both are colloquially abbreviated to 'psycho', psychosis bears little similarity to psychopathy's core features, particularly with regard to violence, which rarely occurs in psychosis, and the distortion of perceived reality, which rarely occurs in psychopathy.
It should also be distinguished from the state of delirium, in that a psychotic individual may be able to perform actions that require a high level of intellectual effort in clear consciousness. Finally, it should be distinguished from mental illness. Psychosis may be regarded as a symptom of other mental illnesses, but as a descriptive concept it is not considered an illness in its own right. For example, persons with schizophrenia can have long periods without psychosis and persons with bipolar disorder and depression can have mood symptoms without psychosis. Conversely, psychosis can occur in persons without chronic mental illness as a result of an adverse drug reaction or extreme stress.
Psychosis has been of particular interest to critics of mainstream psychiatric practice who argue that it may simply be another way of constructing reality and is not necessarily a sign of illness. For example, R. D. Laing has argued that psychosis is a symbolic way of expressing concerns in situations where such views may be unwelcome or uncomfortable to the recipients. Thomas Szasz has focused on the social implications of labelling people as psychotic, a label which he argues unjustly medicalises different views of reality so such unorthodox people can be controlled by society.
Etymology: The word psychosis was first used by Ernst von Feuchtersleben in 1845 as an alternative to insanity and mania and stems from the Greek psykhe (mind) and osis (diseased or abnormal condition). The word was used to distinguish disorders which were thought to be disorders of the mind, as opposed to neurosis, which was thought to stem from a disorder of the nerves.
Psychotic experience
A psychotic episode can be significantly coloured by mood. For example, people experiencing a psychotic episode in the context of depression may experience persecutory or self-blaming delusions or hallucinations, whilst people experiencing a psychotic episode in the context of mania may form grandiose delusions or have an experience of deep religious significance.
Although usually distressing and regarded as an illness process, some people who experience psychosis find beneficial aspects and value the experience or revelations that stem from it.
Hallucinations
Hallucinations are defined as sensory perception in the absence of external stimuli. Psychotic hallucinations may occur in any of the five senses and take on almost any form, which may include simple sensations (such as lights, colours, tastes, smells) to more meaningful experiences such as seeing and interacting with fully formed animals and people, hearing voices and complex tactile sensations.
Auditory hallucinations, particularly the experience of hearing voices, is a common and often prominent feature of psychosis. Hallucinated voices may talk about, or to the person, and may involve several speakers with distinct personas. Auditory hallucinations tend to be particularly distressing when they are derogatory, commanding or preoccupying.
Delusions and paranoia
Psychosis may involve delusional or paranoid beliefs. Karl Jaspers classified psychotic delusions into primary and secondary types. Primary delusions are defined as arising out-of-the-blue and not being comprehensible in terms of normal mental processes, whereas secondary delusions may be understood as being influenced by the person's background or current situation.
Thought disorder
Thought disorder describes an underlying disturbance to conscious thought and is classified largely by its effects on speech and writing. Affected persons may show pressure of speech (speaking incessantly and quickly), derailment or flight of ideas (switching topic mid-sentence or inappropriately), thought blocking, rhyming or punning.
Lack of insight
One important and puzzling feature of psychosis is usually an accompanying lack of insight into the unusual, strange or bizarre nature of the person's experience or behaviour. Even in the case of an acute psychosis, the sufferer may seem completely unaware that their vivid hallucinations and impossible delusions are in any way unrealistic. This is not an absolute, however; insight can vary between individuals and throughout the duration of the psychotic episode.
In some cases, particularly with auditory and visual hallucinations, the patient has good insight and this makes the psychotic experience even more terrifying in that the patient realizes that he should not be hearing voices, but does.
Medical understanding of psychosis
There are a number of possible causes for psychosis. Psychosis may be the result of an underlying mental illness such as Bipolar disorder (also known as manic depression), and schizophrenia. Psychosis may also be triggered or exacerbated by severe mental stress and high doses or chronic use of drugs such as amphetamines, LSD, PCP, cocaine or scopolamine. However, incidence of psychosis resulting from a single administration of any drug is rare, although cases have been reported in the medical literature suggesting a person's sensitivities to new compounds can be unpredictable. As can be seen from the wide variety of illnesses and conditions in which psychosis has been reported to arise (including for example, AIDS, leprosy, malaria and even mumps) there is no singular cause of a psychotic episode.
The division of the major psychoses into manic depressive insanity (now called bipolar disorder) and dementia praecox (now called schizophrenia) was made by Emil Kraepelin, who attempted to create a synthesis of the various mental disorders identified by 19th century psychiatrists, by grouping diseases together based on classification of common symptoms. Kraepelin used the term 'manic depressive insanity' to describe the whole spectrum of mood disorders, in a far wider sense than it is usually used today. In Kraepelin's classification this would include 'unipolar' clinical depression, as well as bipolar disorder and other mood disorders such as cyclothymia. These are characterised by problems with mood control and the psychotic episodes appear associated with disturbances in mood, and patients will often have periods of normal functioning between psychotic episodes even without medication. Schizophrenia is characterized by psychotic episodes which appear to be unrelated to disturbances in mood, and most non-medicated patients will show signs of disturbance between psychotic episodes.
Psychotic episodes may vary in duration between individuals. In brief reactive psychosis, the psychotic episode is related directly to a specific stressful life event so patients may spontaneously recover normal functioning within two weeks. In some rare cases, individuals may remain in a state of full blown psychosis for many years, or perhaps have attenuated psychotic symptoms (such as low intensity hallucinations) present at most times.
Patients who are undergoing a brief psychotic episode may have many of the same symptoms as a person who is psychotic as a result of (for example) schizophrenia, and this fact has been used to support the notion that psychosis is primarily a breakdown in some specific biological system in the brain. The dopamine hypothesis of psychosis was an early, and still popular, example of a theory based on this assumption. However, it is controversial how much weight should be given to such exclusively biological theories as it has become clearer that a wide range of influences (including environmental, social and childhood development factors) may contribute to the final experience of psychosis.
It has also been argued that psychosis exists on a continuum as everybody may have some unusual and potentially reality-distorting experiences in their life. This has been backed up by research showing that experiences such as hallucinations have been experienced by large numbers of the population who may never be impaired or even distressed by their experiences. In this view, people who are diagnosed with a psychotic illness may simply be one end of a spectrum where the experiences become particularly intense or distressing (see schizotypy).