To add to the drama, several movies have given characters a condition known as amnesia. Amnesia is characterized by the loss of one's memories. In anterograde amnesia, a person loses the ability to form new memories. In contrast, retrograde amnesia occurs when someone loses their ability to recall some or all of the events in their life before the onset of the condition. Both of these types of amnesia have been shown to audiences on the big screen, but in many cases there is more flaw than fact to how the condition is portrayed.
In the movie 50 First Dates, the character Lucy Whitmore suffers from what appears to be anterograde amnesia as a result of hitting her head in a car accident. The first flaw in this cinema amnesia is that memory loss rarely occurs following a head injury. The most common causes of amnesia are a stroke, brain infection, or neurosurgery. Second, the idea of memory being wiped clean every night is not plausible. Memory loss has no specific time where things are suddenly forgotten.
Another movie known for its flawed view of amnesia is Overboard. In the movie, Goldie Hawn's character suffers from amnesia as a result of a head injury. Because of this, she drastically changes in her personality and identity. The real cause for such personality change is called dissociative fugue, not amnesia. Another false aspect of amnesia portrayed in the film is the readily reversible effects of the condition. Goldie simply "snaps out of it" in the end, when in reality things would come back gradually.
Amnesia is misrepresented in many movies, including 50 First Dates and Overboard. As a result, many people's perceptions of the condition are skewed. It is important to always think critically to avoid being trapped by false information.
To read more about cinema amnesia see http://scienceblogs.com/neurophilosophy/2009/03/amnesia_in_the_movies.php