Not all illnesses can easily be seen, and disorders that effect the way we think, or the way we perceive the world around us, have a devastating effect on the lives of a patient, as well as on their friends and families. Major depression is a very common mental illness and is the single largest cause of disability worldwide, according to the World Health Organization, with other severe conditions such as schizophrenia also having a large effect.
Currently, these illnesses can only be diagnosed through a patient talking to a psychiatrist. In spite of this, these illnesses are very much biological, with disruptions in how the cells of the brain work and communicate with each other. Together these ultimately cause the symptoms patients experience. These conditions are highly complex, however, and a lot more research into the biological causes are required if we are to develop new tools to both diagnose and treat patients more successfully.