Global cerebral dysfunction characterized by alteration in cognitive function and consciousness is known as -
Infection (like pneumonia) is one of the cause of delirium.
Altered sensorium, disorientation to place (Patient thinks he is in jail) and person (not recognizing the doctor and staff), and hallucinations (scorpions attacking him) suggest the diagnosis of delirium.
Acute anxiety
Depression
Delirium
Dementia