What is psychosis and how do you tell if you have it?

he idea that psychosis can exonerate a person who committed a crime is very widespread. But ‘psychosis’ is neither a medical entity nor a legal term. The legal term is ‘insanity.’ If a person really is insane, the case is unlikely to get to trial. One legal book puts it this way:

“Because the person who was insane at the time of his conduct is likely to be incompetent at the time of trial, he may be declared incompetent to stand trial and then committed.” ^[1]

The thinking seems to be if a person has “sufficient present ability to consult with his lawyer . . . and has a rational as well as factual understanding of the proceedings against him,” then the person is fit to stand trial. The two terms, according to this interpretation, are essentially synonymous.

It's sometimes said that if someone thought he or she was opening a jar of peanut butter but was actually committing come terrible crime, an insanity defense might be appropriate. The advantage to the perpetrator is obvious: since there is no effective treatment and no sure way to know whether a person is cured, they stand a good chance of being released after a short time. But they will also suffer from lifelong stigma and permanent harm from the drugs they will be forced to take.

What is psychosis

Psychosis is not a recognized neurological disease, but a collection of symptoms that lies on the far side of the border between neurology and psychiatry. Attempts to classify psychoses failed because a huge variety of things, from schizophrenia, epilepsy, encephalitis, dementia, toxins, drugs (especially methamphetamine and cannabis), and viral infections, can cause ‘psychosis.’ Neuropathology textbooks typically mention psychosis and then immediately change the subject to schizophrenia. To find the answer we must turn to the psychiatry literature.

The DSM, the psychiatrists’ bible, comes closer to a definition. According to the DSM there are three classifications:

1. Brief psychotic disorders

2. Schizophreniform disorder

3. Schizophrenia

The symptoms are identical: delusions, hallucinations, disorganized speech, abnormal psychomotor behavior, and ‘negative symptoms’ such as diminished emotional expression and avolition. The only difference among them is the duration: the first lasts up to one month; the second lasts 1–6 months, and the third lasts more than 6 months. If it has peripartum onset, the DSM says it must be within 4 weeks postpartum.

Postpartum psychosis

Postpartum psychosis (PPP) is a psychiatric emergency requiring treatment and hospitaliz­ation, which isolates the patient from at-risk family members and protects against suicide. It is thought ^[2] that PPP could be the first presentation of bipolar disorder because PPP sufferers have a 50–80% chance of having another psychotic episode, usually a bipolar disorder, later in life. The typical onset is 3–10 days after giving birth, with the peak occurring from days 1 to 14. It rarely occurs later than 90 days after giving birth.^[5] Higher maternal age confers higher risk.^[5]

Symptoms are insomnia, irritability, mood changes, extreme confusion, disorientation, mixed mania and depression, and homicidal or suicidal thoughts. Treatments include lithium, antipsychotics and benzodiazepines, electro­convul­sive therapy, and hospitalization.

About 25–50% of women with PPP will have another episode in subsequent postpartum periods. One study found that 32% will have affective or psychotic symptoms outside the peripartum.

Doctors speculate that PPP could result from low estrogen, sleep deprivation, or history of mistreatment during childhood. Stressful life events are not a factor. History of bipolar disorder is a strong risk factor and some authors ^[3] recommend notifying CPS if such a patient becomes pregnant. Another theory is a disorder in folate metabolism. But all attempts to find a genetic cause have so far failed. A few studies claim that steroid sulfatase deficiency might contribute. Steroid sulfatase is ^[3] an enzyme coded on the X chromosome that hydrolyzes estrogen precursors dehydro­epiandro­sterone sulfate (DHEAS), estrone sulfate, and cholesterol sulfate to their active forms. A deficiency causes skin problems.

Autoimmune disorders

An important new theory of psychosis is anti-NMDA receptor encephalitis, an autoimmune disorder that manifests with psychosis and closely resembles schizophrenia. Some authors ^[4] propose a gigantic mnemonic (SEARCHFNMDARA)* to describe the symptoms. One problem, they say, is that there has been uncontrolled antibody testing in psychiatric populations. There is resistance to the new emphasis on immunology among psychiatrists, but if ‘psychosis’ is ever to become a legitimate disease entity, the molecular biologists are the ones who will make that happen.

The classical dopamine theory of psychosis has mostly been abandoned, though some researchers say that dopamine hyperactivity (which has long been observed in schizophrenic patients) could be a downstream consequence of glutamate dysregulation in anti-NMDAR encephalitis.

Female rage and responsibility

Among the general public, there is debate about whether PPP is sufficient grounds for diminished responsi­bility. The idea is that, just as alcoholism doesn’t excuse someone from a crime committed while intoxicated, it's everyone’s responsibility to pay attention to their mental state and seek treatment immediately when there’s a problem. A better understanding of psychosis and of the need for immediate treatment and isolation would help, and it is urgently needed.

Indeed, the term ‘psychosis’ gives the false impression that crimes are invariably the result of a medical condition. The newspapers are full of stories about women who think they were rejected or abandoned and exact revenge by torturing or murdering the only things in the universe that have an untarnished soul. Female rage is a real phenomenon and it is beyond the understanding of modern medicine.

* Mnemonic for anti-NMDAR encephalitis (SEARCHFNMDRA)^[4]

• Sleep dysfunction

• Excitement / disinhibition / manic behavior

• Agitation / aggression

• Rapid onset

• Children / young adult

• History is negative

• Fluctuating catatonia

• Negative and positive symptoms

• Memory deficit / amnesia for the illness period

• Decrease in verbal output / mutism

• Antipsychotic intolerance

• Rule out neuroleptic malignant syndrome (NMS)

• Antibody test

sep 07 2026, 8:45 am. updated sep 08 2026, 4:15 am