The point in time when symptoms of severe mental illness, including a lack of reality, first appear.
This initial psychotic episode normally occurs during the teens and 20s, though some experience that break later in life, according to this National Institute of Mental Health fact sheet. There are a host of causes for psychoses, and those causes vary from person to person. Some breaks are rooted in personal genetics, trauma, substance abuse/use, physical illness, injury or myriad mental health conditions.
Early warning signs of a break can include sleeplessness; hallucinations; delusions; seeing shadows and/or light flashing; hearing voices; smelling or tasting things that others don’t; being suspicious of others; isolation; decline in personal appearance and hygiene; abrupt decline in school or work performance, etc.
Schizophrenia is the common psychosis, but that list also includes, among others, delusional disorder, schizoaffective disorder and substance-induced psychotic disorder.