Psychosis

Psychosis or psychoticism is when someone exhibits a wide range of "incongruent odd, eccentric, or unusual" behaviors and thoughts. A sufferer holding false beliefs that are firm despite solid evidence to the contrary, known as delusions, can characterize this.

Psychoticism is considered to be a broad personality trait in Diagnostic and Statistical Manual of Mental Disorders (DSM). It can also be part of a mental disorder, e.g. Schizophrenia is the mostly widely known psychotic disorder, or certain personality disorders e.g. schizotypal or paranoid personality disorders. Psychotic disorders can last anything from a day to many years.

To repeat, a delusion is a false belief about external reality that is evidently false or that remains unchanged despite obvious evidence to the contrary. It is commonly (but not exclusively) the result of a mental disorder, which could be a psychotic disorder such as schizophrenia. Delusions are often bizarre, meaning improbable or impossible but can also be non-bizarre and physically capable of happening despite not being true.

Symptoms
Psychosis may cause a combination of:
 * Delusions
 * Hallucinations — these may be visual, auditory (e.g. hearing voices from heaven and hell) or sensory (e.g. crawling sensations under the skin, known as formation)
 * Disorganized speech, better known as "word salad" — totally incomprehensible or constantly switching between unrelated topics
 * Disorganized behavior or movements, which may include echopraxia (repeating someone else's words), other forms of catatonia, child-like silliness or agitation
 * Loss of all motivation — the person may be unable to wash or change their clothes

Causes
There is a strong genetic link, and evidence that "environmental stress" e.g., child abuse or other stress may be a factor. According to the DSM, possible causes include drug use (PCP, cocaine, and even marijuana or alcohol) or drug withdrawal, certain types of medications including common drugs for asthma, malaria, heart problems, chemotherapy, sleeping tablets and some over the counter drugs, plus toxins like organophosphatess or the bioweapon sarin. Many first episodes of psychosis are induced by drugs. Distress from depression, anxiety, and existential crises can also trigger psychotic episodes.

The stress of retiring due to boxing injury triggered psychosis in Frank Bruno, who was later forcibly sent to a psychiatric hospital and later diagnosed with bipolar disorder.

Violence
Forget the serial killer movies and the screaming press headlines, there's not much risk of aggression or violence in people with schizophrenia or psychotic disorders. Despite the term "psycho", which is more accurate for low-functioning psychopaths, many psychotic symptoms like grossly disorganized, too paranoid to wash, or catatonic are likely to hamper any possible ability to go on a killing spree.

Hostility and aggression can be associated with schizophrenia, although spontaneous or random assault is uncommon. Aggression is more frequent for younger males and for individuals with a past history of violence, non-adherence with treatment, substance abuse, and impulsivity. It should be noted that the vast majority of persons with schizophrenia are not aggressive and are more frequently victimized than are individuals in the general population.

Suicide is the cause of death for 5% of people with schizophrenia and 20% attempt suicide.

Tarditive dyskinesia
Through nearly 40 pages of the psychotic symptoms in the DSM manual, there's the odd twitching known as tarditive dyskinesia. Involuntary face, lower tongue, jaw, and sometimes extremities movements aren't technically a sign of psychosis - they are a side effect of long term medication use, particularly older antipsychotic drugs. Sometimes they go after discontinuing medication, sometimes it's permanent. This is different to the jerking agitation and repetitive movements that are a symptom of psychosis.

That's not all, folks!
Putting aside personality disorders and psychotically-based disorders like schizophrenia, psychosis can also happen be a symptom of bipolar disorder type I (manic depression with mania), depression with psychotic features, and at times some of the non-psychotic personality disorders cause cause episodes of psychosis.

When "delusions" are true
While many of the marking symptoms of psychosis, such as total disconnect from consensus reality, are not difficult to recognize, assessing whether a specific belief is a "delusion" depends on the person assessing as well as what their beliefs and previous experiences are. This of wrongly judging a belief based in reality as "false" is more likely to happen to people who are quite unusual or eccentric, and is far more likely to happen to women, in the context of the 19th century at the very least. The use of the "delusional" label or a psychotic diagnosis has also been used to attempt to silence whistleblowers, orchestrate cover-ups or avoid political scandals. Bell, V. (4 Aug 2013). You needn't be wrong to be called delusional. The Guardian.

The or Cassandra syndrome is a similar concept: someone (usually a woman) is very emotional or "hysterical" and combined with her implausible disclosures or socially/politically unacceptable actions he or she is discredited and treated as mentally ill, effectively detracting from the original issue that was raised. Typically a dysfunctional relationship with a strong male disclosures is also present, with the influence of the male "Apollo" used to discount the disclosures.