what is meant by the second symptom mentioned above?
It is an abnormal condition of the mind that results in difficulties determining what is real and what is not real
Psychosis
Psychosis is an abnormal condition of the mind that results in difficulties determining what is real and what is not real. 
what does single episode major depressive disorder mean UNANSWERABLE what are symptoms of  this disorder? Low mood, symptoms of psychosis; like delusions and hallucinations are some of them how it is caused? Childhood abuse, either physical, sexual or psychological are all risk factors how this can be prevented? Eating large amounts of fish, Behavioral interventions, such as interpersonal therapy and cognitive-behavioral therapy which medicines can prove to be helpful against this disorder? Omega-3 fatty acids fish oil supplements, celecoxib are few
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Psychosis [SEP] Introduction
Psychosis is an abnormal condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations. Other symptoms may include incoherent speech and behavior that is inappropriate for the situation. There may also be sleep problems, social withdrawal, lack of motivation, and difficulties carrying out daily activities. Psychosis is rare in adolescents but can have serious outcomes. Psychosis has many different causes. These include mental illness, such as schizophrenia or bipolar disorder, sleep deprivation, some medical conditions, certain medications, and drugs such as alcohol or cannabis. One type, known as postpartum psychosis, can occur after giving birth.