Despite occuring only rarely, amnesia (or memory loss) has featured often in Hollywood films for almost a century. By 1926, at least 10 silent films which used amnesia as a plot device had been made; more recent productions, such as 50 First Dates and Eternal Sunshine of the Spotless Mind, are therefore part of a well established tradition.
In a review published in the British Medical Journal in 2004, clinical neuropsychologist Sallie Baxendale of the Institute of Neurology in London points out that cinematic depictions of amnesia are consistenly inaccurate, and usually "bear no relation whatsoever to any authentic neurological or psychiatric condition".
In her review, Baxendale examines common misconceptions of amnesia found in the cinema, and suggests that knowledge of them can guide clinicians when informing patients and their relatives about diagnoses. She also points out several exceptional films which depict amnesic syndromes accurately.
In the romantic comedy 50 First Dates (2004), Adam Sandler plays veterinarian Henry Roth, who falls for Lucy Whitmore (played by Drew Barrymore) after meeting her in a cafe one morning. The two hit it off, and arrange to meet again. The following day, Roth returns to the café to meet her, but she claims to have no recollection of him. As he leaves, the owner of the café takes him to one side, and explains that Whitmore "lost her short-term memory" after a "terrible car accident". We also learn that she can form new memories during the day, which are then wiped clean during her sleep, so that she wakes up to a "clean slate" every morning.
50 First Dates propagates a number of misconceptions which are common in the films which refer to amnesia. Whitmore's amnesia is the result of a head injury incurred in the car accident; other amnesic characters may lose their memory after being assaulted, or bumping their head in some other way. In reality, memory loss rarely occurs following a head injury; it is most often caused by stroke, brain infection or neurosurgery. The idea that new memories are wiped clean at night is also unrealistic, and unlike any documented amnesic syndrome.
In many cases of cinematic amnesia, head injuries lead to loss of memory of earlier events (retrograde amnesia), but the character usually goes on to lead an otherwise normal life. Real patients who incur brain damage usually suffer from anterograde amnesia - they lose the ability to form new memories, but their memories of events that occured before the amnesia often remain intact. Often they lose memories of many important aspects of their lives - of loved ones and daily routines - and so day-to-day functioning is affected severely.
Amnesic film characters often undergo personality changes or a loss of identity. This confuses amnesia with a poorly-understood condition called dissociative fugue. It also blurs the distinction between the causes of the different amnesic syndromes, as the characters experience psychiatric symptoms, which in reality do not have an organic cause, which are attributed to neurological damage.
Personality changes after a head injury can be seen in the 1987 film Overboard, starring Goldie Hawn and Kurt Russell. Hawn plays a rich and spoilt socialite who loses here memory after bumping her head when falling from her yacht. The character then undergoes a sudden transformation - she becomes warm-hearted and loving and is duped into raising the children of Russel's character as her own. Her memory loss, like that of most other characters, is readly reversible - towards the end of the film, it is cured by another bump on the head. In others, the memories return when they see a familiar object or person. Both of these scenarios are equally implausible.
Memento (2000) is a rare example of a film which depicts amnesia accurately. It is apparently inspired in part by the case of Henry Molaison (H.M.), the famous amnesic who died last December. Guy Pearce plays Leonard, who suffers severe anterograde amnesia after sustaining a head injury in an attack in which his wife is killed. Unlike most amnesic characters, Leonard retains his identity and the memories of events that occurred before the attack, but loses all ability to form new memories. The film's fragmented narrative powerfully depicts how difficult everyday life would be for a severely amnesic patient - Leonard spends much of the film frantically scribbling scraps of information on pieces of paper and, once he has estalished something to be a fact, has it tattooed onto his body.
Another accurate depiction of amnesia is found in the CGI-animated film Finding Nemo (2003). One of the characters, a reef fish called Dory, has a profound memory deficit which, to frustration of her peers, prevents her from learning or retaining any new information, remembering names, or knowing where she is going. As a result, she gets lost when left alone and is often found in a state of confusion. The exact origin of Dory's impairment is not mentioned in the film, but her memory loss accurately reflects the difficulties faced by amnesic patients and those who know them.
Realistic amnesic characters are few and far between in the cinema. Baxendale refers to only one other film, called Se Quien Eres (I Know Who You Are, 2000), containing an accurate depiction of amnesia, in the form of a patient with Korsakoff's Syndrome, the amnesic syndrome condition associated with chronic alcoholism. However, Columbia Pictures announced last month it has acquired the rights to make a film about the life of H.M., based on a book which is to be written by Susanne Corkin, the MIT researcher who worked with him for 4 years.
On a related subject is Rashomon (1950), Akira Kurosawa's masterful examination of the reconstructive nature memory Rashomon depicts a crime as seen from the perspective of four eyewitnesses. As each gives their testimony, the same event is described in four radically different ways. Each of the testimonies contradicts the others, and each of the witnesses initially insists that their version of the event is the right one. Then, as they consider each others' descriptions, something which at first seemed clear becomes utterly confusing, as all the characters and the audience begin to question the accuracy of their own memories.