The symptoms of schizophrenia vary in quality and intensity from individual to individual, but delusions or a failure to recognize what is real is characteristic. The delusions of schizophrenia can cause hallucinations in sight (visual hallucination), sound (auditory hallucination), and/or touch (tactile hallucination). Other symptoms of schizophrenia include disordered or confused thought. This can be associated with talking nonsense and disorganized speech. Both a decrease in social interactivity or being socially withdrawn and agitation are common. This can lead to other socially negative symptoms and unusual behavior.

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