Conversely, the breakdown in the ability of a person to intrapersonally communicate is associated with mental illness (Dance & Larson, 1976).
Those suffering from the symptoms of mental illness disconnect from their internal voice. When someone who suffers from mental illness is exhibiting symptoms usually they stop having intrapersonal narrative. This is caused by the individuals mistrust of their own brain. They know somethings wrong so they cannot rely on their thoughts to be based on reality. Once treated individuals slowly learn to trust oneself again.