 After this instance, the criteria for diagnosis of prosopamnesia were refined from a list of specific symptoms to a more formal measure which requires a normal score on a facial perception test and a significantly low score on a facial memory test (such as those developed in Cambridge).In the second case of prosopamnesia diagnosis, the patient reported a lifetime deficit in the ability to remember faces.This indicated that the damage to the face processing neural circuit causing prosopamnesia can be either genetic (developmental type) or incidental brain damage (acquired type).