Short answers, pulled from the story.
Karl Friedrich Canstatt introduced the word psychosis into psychiatric literature in 1841 as a shorthand for psychic neurosis. This term described what was then considered a psychological manifestation of brain disease rather than a specific mental illness.
Common symptoms include delusions, hallucinations, and disorganized thoughts or speech that describe a person's state rather than a particular diagnosis like schizophrenia. Causes range from childhood trauma which predicts adolescent and adult psychosis with three times higher likelihood to severe sleep deprivation inducing episodes within minutes inside an empty room devoid of light and sound.
In Accra Ghana subjects describe voices they hear as having spiritual meaning and often report them as positive experiences while people in Chennai India describe their hallucinations as kin family members or close friends offering guidance. Muslim majority countries believe mental disorders such as psychosis are caused by jinn or spirits whereas countries like the United States predominantly use biomedical understanding where subjects report violent content and self-describe as crazy.
Blood tests measure thyroid-stimulating hormone to rule out hypo- or hyperthyroidism and vitamin B12 serum levels for pernicious anemia. The Brief Psychiatric Rating Scale assesses 18 symptom constructs including hostility suspicion and grandiosity based on clinician interviews while the Positive and Negative Syndrome Scale contains 30 items used during initial assessment and follow-up periods.
The first clinical trial of antipsychotics took place in 1952 when chlorpromazine passed trials becoming the first approved medication. This drug marked the advent of dopamine antagonists though side effects included irreversible Parkinsonian symptoms like tardive dyskinesia.