Thus, the brain can learn to be independent of the impaired hippocampus, but only to a certain extent. For example, older memories are consolidated over time and in various structures of the brain, including Wernickes area and the neocortex, making retrieval through alternate pathways possible. Diagnosis
Testing for retrograde amnesia
As previously mentioned, RA can affect peoples memories in different degrees, but testing is required to help determine if someone is experiencing RA. Several tests exist, for example, testing for factual knowledge such as known public events. A problem with this form of testing is that people generally differ in their knowledge of such subjects. The tests also have to be changed regularly to adapt to the period of time patients have been alive, and include questions about autobiographical events that range in amount of detail. Due to the nature of the information being tested, it is often difficult to verify the accuracy of the memories being recalled, especially if they are from a distant past. One way to confirm information is by consulting close family members or caregivers. Another problem that arises is that this type of testing can result in a significant amount of data that needs to be processed and confirmed. Other ways to test someone is via autobiographical knowledge using the Autobiographical Memory Interview (AMI). A test that comprises names of relatives, personal information, and job history. The AMI was created by Kopelman, Wilson, and Baddeley (1990). This information could help  determine if someone is experiencing RA and the degree of memory affected.
Patient CD reported disorientation of place and time following his injuries as well as relearning previously learned information and activities (e.g., using a razor). EF was examined and found to be very confused about social norms (e.g., appropriate attire outside his home). EF exhibited memory loss of his personal experiences (e.g., childhood), and the impaired ability to recognize his wife and parents. JG is the first recorded patient with isolated RA. GH, a mother and a wife, had surgery in August 2002. When GH woke up after the surgery, she believed it was May 1989. Due to her amnesia, GH experienced great difficulty in her social environment, being overwhelmed by relationships to others. DH, a learning disabilities instructor and husband, sustained a closed head injury. He did not show any normal signs of memory loss but he could not recall anything prior to the accident. CDA is a 20-year-old man who fell and experienced head trauma after being unconscious for a little less than an hour. He had a self-identity loss and a retrograde deficit limited to the autobiographical events 5 years before the trauma. He often showed signs of spontaneous speech that was iterative and sometimes incoherent. When he saw his family and friends, he was shocked at how old they looked because he remembered them from 5 years earlier. This case also included amnesia for procedural skills like the fear of shaving or driving, which ultimately was overcome. There were no psychological, neuropsychological, or brain damage problems.