Treating alcoholism and preventing alcohol and illicit drug use can prevent further damage, but in most cases will not recover lost memory.Although improvements occur when patients receive certain treatments, there is still no actual cure remedy for amnesia so far. To what extent the patient recovers and how long the amnesia will continue depends on the type and severity of the lesion. History
French psychologist Theodule-Armand Ribot was among the first scientists to study amnesia. He proposed Ribots Law which states that there is a time gradient in retrograde amnesia. The law follows a logical progression of memory loss due to disease. First, a patient loses the recent memories, then personal memories, and finally intellectual memories. He implied that the most recent memories were lost first.Case studies have played a large role in the discovery of amnesia and the parts of the brain that were affected. The studies gave important insight into how amnesia affects the brain. The studies also gave scientists the resources into improving their knowledge about amnesia and insight into a cure or prevention. There are several extremely important case studies: Henry Molaison, R.B, and G.D.

Henry Molaison
Henry Molaison, formerly known as H.M., changed the way people thought of memory. The case was first reported in a paper by William Beecher Scoville and Brenda Milner in 1957. He was a patient who had  severe epilepsy attributed to a bicycle accident at the age of nine.
He also had a left thyroid lobectomy because of the severe loss of blood in his left lobe. He began having cardiac problems as a result of the surgery and became very agitated. Even five days after being released from the hospital he was unable to remember what had happened to him. Aside from memory impairment, none of his other cognitive processes seemed to be affected. He did not want to be involved in much research, but through memory tests he took with doctors, they were able to ascertain that his memory problems were present for the next 9.5 years until his death. After he died, his brain was donated to science, photographed, and preserved for future study. In fiction
Global amnesia is a common motif in fiction despite being extraordinarily rare in reality. In the introduction to his anthology The Vintage Book of Amnesia, Jonathan Lethem writes:

Real, diagnosable amnesia – people getting knocked on the head and forgetting their names – is mostly just a rumor in the world. Its a rare condition, and usually a brief one. In books and movies, though, versions of amnesia lurk everywhere, from episodes of Mission Impossible to metafictional and absurdist masterpieces, with dozens of stops in between. Amnesiacs might not much exist, but amnesiac characters stumble everywhere through comic books, movies, and our dreams. Weve all met them and been them.