Schizophrenia is a brain disease that interferes with normal brain functioning. It causes affected people to exhibit odd and often highly irrational or disorganized behavior. Because the brain is the organ in the body where thinking, feeling and understanding of the world takes place (where consciousness exists), a brain disease like schizophrenia alters thinking, feeling, understanding and consciousness itself in affected persons, changing their lives for the worse.
Psychosis and the loss of reality
A defining feature of schizophrenia or paranoid schizophrenia is psychosis. Psychosis occurs when a person loses the ability to discriminate between real and 'imagined' experiences, and therefore loses touch with reality.
While the hallucinations and delusions characteristic of psychosis are 'imagined' in the sense that they do not have a solid, consistent basis in reality, they are nevertheless unavoidable and appear as real as other more reality-based perceptions to the people who experience them.
Schizophrenic persons have little choice but to take their hallucinations seriously as their malfunctioning brains cause them to experience hallucinations uncontrollably with the force of real sensations. Hallucinations are thus a sort of 'virtual reality' that schizophrenic people become trapped within, and the delusions that form around these hallucinations are a natural response to this unintentionally altered perception.
People with schizophrenia tend to think and act differently than other people because the occurrence of hallucinations, delusions and other symptoms characteristic of schizophrenia causes them to experience reality very differently than other people. This loss of reality can be terrifying for both schizophrenic people, who struggle mightily to make sense of their inner perceptual chaos, and for the people around them who grapple with trying to understand why their loved ones are acting in such odd and seemingly disorganized ways.