Reactionary disturbances effect emotional and motivational responses as well, but reflect the failure to cope with environmental demands. Someone with this might withdraw from the environment that they are placed in because they no longer know how to handle the cognitive resources. Nutritional deficiency
RA has been found among alcohol-dependent patients who have Korsakoffs syndrome. Korsakoffs syndrome patients develop retrograde amnesia due to a thiamine deficiency (lack of vitamin B1). Also, chronic alcohol use disorders are associated with a decrease in the volume of the left and right hippocampus.These patients regular diet consists mostly of hard alcohol intake, which lacks the necessary nutrients for typical development and maintenance. Therefore, after a prolonged time consuming primarily alcohol, these people undergo memory difficulties and ultimately develop RA. However, some of the drawbacks of using Korsakoff patients to study RA is the progressive nature of the illness and the unknown time of onset. Infections
Infections that pass the blood–brain barrier can cause brain damage (encephalitis), sometimes resulting in the onset of RA. In the case of patient SS, the infection led to focal or isolated retrograde amnesia where there was an absence of or limited AA. Brain scans show abnormalities in the bilateral medial temporal lobes, including two thirds of the hippocampal formation and the posterior part of the amygdala. Surgery
Henry Molaison had epilepsy that progressed and worsened by his late twenties. The severity of his condition caused him to undergo surgery in an effort to prevent his seizures.
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.