<prompt> The following is suggestive of an organic cause of behavioral symptoms:Formal thought disorderAuditory hallucinationsDelusion of guiltProminent visual hallucinations  <response>: The presence of prominent visual hallucinations is a strong pointer towards an organic cause i.e. a disturbance of brain parenchyma such as tumors. Although visual hallucinations can occur in schizophrenia, however, they are not as common as auditory hallucinations. Formal thought disorders are characteristic of schizophrenia. Delusion of guilt can be a feature of schizophrenia or depression with psychotic symptoms. 