Hallucination and suicide have a strong relationship. People who hallucinate tend to die by suicide or attempt suicide. There is a strong genetic link and most people who hallucinate have a strong family history where family members have experienced similar symptoms.
Hallucination can be auditory where the sufferer will hear actual voices (not thoughts), visual where the person will see people who are not real or combination of both.
Hallucination is caused by many mental illnesses. It can be difficult to diagnose these disorders because many normal appearing people may suffer from hallucination due to some mental illnesses and live a normal life and behave normally.
People who suffer from mental illnesses that have hallucination symptoms have a difficulty interpreting reality. That is, it is difficult for them to tell the difference between what is real and what is the hallucination. Over a long period of time their world of reality and what is not become one if not diagnosed and treated.
How can hallucinations contribute to suicide?
Many people that hallucinate from mental disorders hear voices or see imaginary people who talk to them. These voices or imaginary people maybe telling uncomfortable things to them, demoralizing, threatening or even commanding or instructing them to do things. The sufferers have no control over this. Majority of sufferers do not act on these voices or carry out the commands from the imaginary people. However, some people will follow their commands or instructions and can die by suicide as a result of acting on the commands. The chances of dying by suicide or attempting suicide due to acting on commanding hallucinations (whether voices or people talking) are higher in young people. These voices or imaginary people are real to the sufferers. It is not a like a thought running through their head but rather like someone in the room and tells them to do something. The voices and the imaginary people can be very annoying and persistent and do not go away not matter how hard the sufferer tries to avoid them. It can only be controlled by medical assistance.