Schizophrenia is not, as many people believe, a split personality. When someone becomes unwell, they are likely to show drastic changes in their behaviour. They may be upset, anxious, confused and suspicious of other people. They may be reluctant to believe they need help. Doctors will look for various 'positive' symptoms (strange thinking, hallucinations and delusions) and 'negative' symptoms (apathy, emotional flatness, inability to concentrate, wanting to avoid people or to be protected).