The term schizophrenia translates roughly as "splitting of the mind", and comes from the Greek σχίζω (schizo, "to split" or "to divide") and φρήν (phrēn, "mind").

Despite its etymology, schizophrenia is not synonymous with dissociative identity disorder, also known as multiple personality disorder or "split personality"; in popular culture the two are often confused. People with schizophrenia are generally not more violent or dangerous than other members of the population.

Schizophrenia (from the Greek word σχιζοφρένεια, "split mind") is a psychiatric diagnosis that describes a mental disorder characterized by impairments in the perception or expression of reality and by significant social or occupational dysfunction. A person experiencing schizophrenia is typically characterized as demonstrating disorganized thinking, and as experiencing delusions or auditory hallucinations.


Schizophrenia is often described in terms of "positive" and "negative" symptoms. Positive symptoms include delusions, auditory hallucinations and thought disorder and are typically regarded as manifestations of psychosis. Negative symptoms are so named because they are considered to be the loss or absence of normal traits or abilities, and include features such as flat, blunted or constricted affect and emotion, poverty of speech and lack of motivation. Some models of schizophrenia include formal thought disorder and planning difficulties in a third group, a "disorganization syndrome".

Additionally, neurocognitive deficits may be present. These may take the form of reduced or impaired psychological functions such as memory, attention, problem-solving, executive function or social cognition.

Although no common cause of schizophrenia has been identified in all individuals diagnosed with the condition, currently most researchers and clinicians believe it results from a combination of both brain vulnerabilities (either inherited or acquired) and stressful life-events. This widely-adopted approach is known as the 'stress-vulnerability' model, and much scientific debate now focuses on how much each of these factors contributes to the development and maintenance of schizophrenia.

It is also thought that processes in early neurodevelopment are important, particularly prenatal processes. In adult life, particular importance has been placed upon the function (or malfunction) of dopamine in the mesolimbic pathway in the brain. This theory, known as the dopamine hypothesis of schizophrenia largely resulted from the accidental finding that a drug group which blocks dopamine function, known as the phenothiazines, reduced psychotic symptoms. However, this theory is now thought to be overly simplistic as a complete explanation. These drugs have now been developed further and antipsychotic medication is commonly used as a first-line treatment. Although effective in many cases, these medications are not well tolerated by some patients due to significant side-effects. The positive symptoms are more responsive to medications; negative symptoms being less so.

Differences in brain structure have been found between people with schizophrenia and those without. However, these tend only to be reliable on the group level and, due to the significant variability between individuals, may not be reliably present in any particular individual. Significant brain atrophy and enlarged ventricles are the most conspicuous of such differences.



To be diagnosed as having schizophrenia, a person must display:

A) Characteristic symptoms: Two or more of the following, each present for a significant portion of time during a one-month period (or less, if successfully treated)
delusions
hallucinations
disorganized speech (e.g., frequent derailment or incoherence; speaking in abstracts). See thought disorder.

grossly disorganized behavior (e.g. dressing inappropriately, crying frequently) or catatonic behavior
negative symptoms, i.e., affective flattening (lack or decline in emotional response), alogia (lack or decline in speech), or avolition (lack or decline in motivation).

Note: Only one Criterion A symptom is required if delusions are bizarre or hallucinations consist of hearing one voice participating in a running commentary of the patient's actions or of hearing two or more voices conversing with each other.


B) Social/occupational dysfunction: For a significant portion of the time since the onset of the disturbance, one or more major areas of functioning such as work, interpersonal relations, or self-care, are markedly below the level achieved prior to the onset.


C) Duration: Continuous signs of the disturbance persist for at least six months. This six-month period must include at least one month of symptoms (or less, if successfully treated) that meet Criterion A.
Additional criteria (D, E and F) are also given that exclude a diagnosis of schizophrenia if symptoms of mood disorder or pervasive developmental disorder are present. Additionally a diagnosis of schizophrenia is excluded if the symptoms are the direct result of a substance (e.g., abuse of a drug, medication) or a general medical condition.




Dissociative identity disorder was initially named multiple personality disorder,Regardless of whether the disorder is termed dissociative identity disorder or multiple personality disorder, it is in no way related to schizophrenia. Although schizophrenia and dissociative identity disorder are commonly linked in the minds of lay people, it is a misconception.



Dissociative Identity Disorder (DID), formerly known as multiple personality disorder, is a disorder in which a person has more than one discrete, separate identity. Each identity is unique, and has its own sets of memories, ideas, thoughts, ways of thinking, and purposes. One identity may be the protector, while another may be a child. On average, a person with DID has between 8 and 13 separate personalities. DID generally results from a severe traumatic experience during the early childhood years.


Dissociation is a complex mental process that provides a coping mechanism for individuals confronting painful and/or traumatic situations. It is characterized by a dis-integration of the ego. Ego integration, or more properly ego integrity, can be defined as a person's ability to successfully incorporate external events or social experiences into their perception, and to then present themselves consistently across those events or social situations. A person unable to do this successfully can experience emotional dysregulation, as well as a potential collapse of ego integrity. In other words, this state of emotional dysregulation is, in some cases, so intense that it can precipitate ego dis-integration, or what, in extreme cases, has come to be referred to diagnostically as dissociation.

Dissociation describes a collapse in ego integrity so profound that the personality is considered to literally break apart. For this reason, dissocation is often referred to as "splitting" or "altering". Less profound presentations of this condition are often referred to clinically as disorganization or decompensation. The difference between a psychotic break and a dissociation, or dissociative break, is that, while someone who is experiencing a dissociation is technically pulling away from a situation that s/he cannot manage, some part of the person remains connected to reality. While the psychotic "breaks" from reality, the dissociative disconnects, but not all the way.

Because the person suffering a dissociation does not completely disengage from his/her reality, s/he may appear to have multiple "personalities". In other words, different "people" (read: personalities) to deal with different situations, but generally speaking, no one person (read: personality) who will retreat altogether.

The French psychoanalyst, Jacques Lacan, taught that all desire is the “desire of the Other.” [1] In plain language, this means that most of our unconscious life is a product of a variety of external social influences. The concept of personality, therefore, although a common term in psychology, really doesn’t mean much because any person is really composed of many diverse, fragmentary—and generally illusory—images of “self.” In the midst of such chaos, psychology can’t heal a personality so much as help a person recognize all these illusions.

These normal fragments of personality are often called ego states, a term derived from the clinical hypnosis work of John & Helen Watkins. In contrast, Multiple Personality Disorder (MPD) is an abnormal condition in which the personality becomes so fragmented that the various parts cannot even communicate with each other.

MPD, now known in diagnostic terminology as Dissociative Identity Disorder (DID), has a fascination as well as a mystery about it. For example, it’s possible to recognize each different personality, or “alter,” from just a few words—in the same way that it’s possible to recognize instantly the voice of a person calling on the telephone. On the other hand, no one can understand the process by which the human brain can create and hold separate and distinct each different personality.

Dissociative Identity Disorder (DID), formerly called Multiple Personality Disorder, has several diagnostic features:
• The presence of two or more distinct identities, each with its own unique, and enduring, way of relating to the world and self.

• At least two of these identities recurrently take control of the person’s behavior.

• An inability to recall important personal information to an extent that is more than ordinary forgetfulness. Classic examples are finding new clothes in your closet which you don’t remember buying; finding yourself in a place or situation and not being able to remember how you got there; having a complete loss of memory for what happened in the previous few days.



DID would not be diagnosed if the symptoms did not cause a major disturbance to the person’s life or if they were due to the physiological effects of a substance (e.g., drugs or alcohol) or a general medical condition.


Symptoms of this particular disorder can include:

depression
anxiety (sweating, rapid pulse, palpitations)
phobias
panic attacks
physical symptoms (severe headaches or other bodily pain)
fluctuating levels of function, from highly effective to disabled
time distortions, time lapse, and amnesia
sexual dysfunction
eating disorders
post traumatic stress
suicidal preoccupations and attempts
episodes of self-mutilation
psychoactive substance abuse

Other symptoms include: Depersonalization, which refers to feeling unreal, removed from one's self, and detached from one's physical and mental processes. The patient feels like an observer of his life and may actually see himself as if he were watching a movie. Derealization refers to experiencing familiar persons and surroundings as if they were unfamiliar and strange or unreal.

Again, doctors must be careful not to assume that a client has MPD or DID simply because they present with some or all of these symptoms. Another factor in the diagnosis is the all squares are rectangles but not all rectangles are squares idea, which is to say that although many of these symptoms may be present in an individual, he or she may not necessarily have DID. For example, someone may have severe PTSD (one symptom) and self mutilate with suicidal ideas, which is 3 of the above symptoms, but will not have DID. In order for DID to be diagnosed, there must be two or more distinctly present personalities.

Persons with dissociative identity disorder are often told of things they have done but do not remember and of notable changes in their behavior. They may discover objects, productions, or handwriting that they cannot account for or recognize; they may refer to themselves in the first person plural (we) or in the third person (he, she, they); and they may have amnesia for events that occurred between their mid-childhood and early adolescence. Amnesia for earlier events is normal and widespread.

A Famous multiple personality disorder case:

Shirley Ardell Mason (January 25, 1923–February 26, 1998) was an American psychiatric patient whose life was documented in the book and film both released under the name Sybil. The book was penned by Flora Rheta Schreiber and published in 1973. The movie was made for TV and was broadcast in 1976. The name Sybil Isabel Dorsett was used in the book and movie to protect her identity.

Sybil told the story of a woman who was treated for multiple personality disorder (now known as dissociative identity disorder) with up to 16 alternate personalities.

Sybil Dorsett was a woman with sixteen separate personalities. At first none of them knew or remembered any of the others. For instance, one personality named Victoria Antoinette Scharleau was a self-assured, sophisticated, attractive blond, and another named Mike Dorsett thought she was male, a builder and carpenter. With multiple personality disorders it is not uncommon for the shy personality to be shocked to wake up naked in bed with a man the sexy personality met the night before. One personality shifts with another and there is no recollection of the prior person. There is a complete discontinuity of consciousness.

This kind of multiple personality disorder is often caused by extreme negative events as a child. In Sybil's case, she was tortured and sexually abused as a young girl. This caused her to break up, literally, because she could not bear the extreme abuse she was subjected to. Through years of therapy Sybil was able to confront the memories and eventually integrate the separate personalities into one. She became a whole person

In recent years, doctors and others have debated whether or not multiple personality disorder really exists. Some claim that Mason's 16 personalities were created by Wilbur's suggestions during therapy. The situation is complicated by the fact that Wilbur never published a report on the case in a peer-reviewed journal. Both Mason and Wilbur are deceased (Wilbur died in 1992), so we may never know more about this unusual story. Swales is said to be researching the facts for a book on Mason's real life as opposed to the account written by Schreiber. He has presented a paper on the subject entitled Gnosis vs. Diagnosis: Sybil's Last Stand at the April 15, 2000, Szasz Symposium held in Syracuse, NY.

Dr. Herbert Spiegel, another psychotherapist who also worked with Mason, asserts that she never had multiple personality disorder and provided tapes to support his assertions. Spiegel concluded that Mason's apparent multiplicity had been iatrogenically induced by Wilbur's encouragement and leading questions and remarks.

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" VALUE HAS A VALUE ONLY IF ITS VALUE IS VALUED "

You are very true. Schizophrenia and Dissociative Identity Disorders are not the same.
One of the basic difference is:
Schizophrenia is a psychotic disorder while Dissociative Identity Disorder is a type of neurosis.
Other Differences include:
1. Schizophrenia is a chronic disorder (usually it needs 6 months to call it schizophrenia according to DSM - IV) while Dissociative Identity Disorder is not a chronic disorder.
2. Presence of Delusion, Hallucination, Disorganized Behavior, Disorganized Speech are the hall mark of Schizophrenia. These are not usually found in Dissociative Identity Disorder.
3. At times Dissociative Disorder patients will behave or work in a different way (in context to his original personality) but behavior is not odd. Schizophrenic behavior is odd.
4. The experiences in Dissociative Identity Disorder are never described as "made" (Schneiderian First Rank symptom). But Schneiderian Fisrt Rank symptoms are found in schizophrenia
5. Treatment in Schizophrenia is with antipsychotic medications, ECT etc. But Dissociative Identity Disorders are treated with Non-Pharmacological treatment(psychotherapy), Abreaction, Anxiolytics