The hippocampus is a part of the brain that is important and responsible for creating and recalling memories, as a result of which Leonard has lost the ability to generate short-term memory. Leonard, in the movie is an insurance agent who through the course of the movie attempts to track his wifes killer and the man responsible for his current state. Leonards condition post accident and the death of his wife, can draw parallels with anterograde amnesia, because he doesnt seem to remember new things, however he retains memories leading up to the accident.
The movie Memento continues Hollywoods fascination with the psyche of the human mind and the genesis of movies based on amnesia is a recurring theme. While the movie does reasonably well in bringing to light the plight of people suffering from anterograde amnesia and similar neurological disorders following brain trauma, it does offer enough loopholes to guarantee criticism from experts. Leonard believes that he does not have amnesia. This is a slight aberration from the true picture of a patient with anterograde amnesia because they do not seem to lose track of who they are and the condition they are suffering from.
It can be argued that some patients with a more seething disease do offer a mixed profile, into which Leonards character can fit. Also, another aspect of cognition is the evidence, that Leonard is still capable of using his procedural memory that includes doing routine things and following certain procedures like driving a car. His declarative memory on the other hand is functional up to the point of his accident. Declarative/explicit memory is essentially conscious memory, while procedural memory is more of a subconscious or unconscious action that can be done.
Additionally, with the hippocampus part of his brain being destroyed, Leonard is incapable of moving things from his short term memory to his long term memory, and thus forgets things if not written down or taken note of. Short-term memory lasts or stores items for less than 20 seconds, unless rehearsed. Thus, in order for him to remember things, and have enough time to write them down, he rehearses them, which allows him to remember them for a longer period of time, and if interrupted that memory is lost. This was portrayed very well in the movie when he hits Natalie.
Natalie throws all of the writing utensils out and then hassles Leonard about his wife and his condition trying to get a reaction so she could in essence set Leonard up, and this she did accomplish. After hitting Natalie, she leaves the house and Leonard rehearses what has just happened while looking for a writing utensil, however there are none to be found. Further, Natalie did not go anywhere when she left the house, she stays in the car and hence, when she slammed the door, purposely, Leonard stopped the rehearsal, and essentially forgot what he was doing, when she comes back into the house, Leonard has no recollection of hitting her.
Thus, although his hand is sore, Leonard does not remember anything that had just occurred, this is due to a stop in rehearsal, and with nothing written for him, he cannot remember what has occurred recently. Leonard is always prepared with something to write on, he always has his camera and his pictures that allow him to remember things; in essence he keeps generating a working memory through out the course of the movie to catch the killer.
Thus, planning is somewhat prevalent in this movie however, although planning requires knowledge about the problem space, or understanding of the constraints of the problem space to mentally construct it well, this is not always available to him. Thus, he is unable to use partial planning, because he did not always think of the outcome that might occur, such as when he killed Natalies boyfriend, and realized he was not the one responsible after he had done it, instead of thinking ahead, before he had done it.
However, with his pictures he was able to get back to particular destinations, and with direction, even if simple, but written down, he was able to use them and plan ahead. Further, in relation to the murder of Natalies boyfriend, counterfactuals were also used, and Leonard is trying to imagine past events differently than they actually did and thus, he burnt the picture that he took of the event because that was the only recollection that he had of the situation. Furthermore, drives, emotions, and problem solving are all clearly used in this movie as well.
Drives, are generally associated with bodily needs whereas emotions are generally associated with more complex personal and social needs, in this case finding the individual who caused Leonard so much pain by raping and murdering his wife, and damaging his memory is very important. In addition, heuristics were also commonly utilized and, heuristics undoubtedly allow individuals to avoid searching paths that are unlikely to lead to a solution, and this is exactly what Leonard is doing with all the facts he was collecting to narrow down the suspect to find out who raped and murdered his wife.
Basically, by slowly collecting and putting together different facts about the rapist and murder of his wife, Leonard was emotionally driven to find the individual responsible for essentially ruining his life. His emotions and feelings of anger, sadness, and love were all affected by his motivation and drives from the pain that was within him due to his present circumstance.
In the movie, many of the cognitive aspects were relevantly presented and shown in a realistic manner however, at times in the movie, things that were not rehearsed or written were remembered, which at times did not allow for it to be fully realistic. This was evident when Dodd was involved, and in the closet and Leonard woke up, and saw that there was a gun in the drawer of the hotel room and it was not his room or his gun, and so when Teddy got there he showed him the gun in the drawer, which probably would not have been remembered realistically.
Thus, to improve, and make this aspect of his condition more realistic, not only at this point in the movie, but throughout the movie would have been for Leonard to actually rehearse things out loud, until he had written things down to clearly show that rehearsal is necessary for things not to be forgotten. 1: Cipolotti L, Bird CM. Amnesia and the hippocampus. Curr Opin Neurol. 2006 Dec;19(6):593-8. Review. 2: Mayes AR, Isaac CL, Holdstock JS, Cariga P, Gummer A, Roberts N. Long-term amnesia: a review and detailed illustrative case study.
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