Schizophrenia Schizophrenia is a severe mental illness,which is most notable for its mixed thought patterns,and unpredictable disturbances in thinking.About one percent of the population is affected by this disease,and half of the inpatients in U.S. mental hospitals are schizophrenics. Symptoms of schizophrenia include delusions,hallucinations,thought disorders,loss of boundaries between self and nonself,inappropriate emotional expressions,lack of motivation,and deterioration of such things as self care,communicating skills,and ambition to work. Delusions-are false beliefs,usually absurd and bizarre.