Charles Bonnet Syndrome (CBS) is a common condition among people who’ve lost their sight, causing them to see things that aren’t really there – known by doctors as an hallucination. Although often quite frightening, CBS hallucinations are caused by sight loss and are not related to any mental health issue.

CBS tends to develop soon after significant sight loss and is caused by how the brain responds loss of vision. When people lose their sight the brain doesn’t receive as much information from the eyes as it is used to and so it tries to fill in the gaps by releasing new images that aren’t really there like random patterns or old pictures stored in the brain from the past.