[MUSIC] The most famous case study in all of memory research involves a man named Henry Molaison. Up until his death in 2008 at the age of 82, he was known only by his initials, HM. What made him so special that psychologists spent decades studying this man? To find out, we need to know what happened to Henry in 1953. Henry experienced epileptic seizures during childhood that worsened as he got older. By the time he was 27, he was incapacitated by major seizures that left him unable to work or lead a normal life. Because medicines could not control his seizures, Henry opted for brain surgery. The goal of the newly developed surgery at that time was to find the area of Henry's brain that was precipitating the convulsions and, providing that area did not serve a vital function, remove it. The surgeon, unable to find any area showing abnormal electrical activity had a hunch that Henry's seizures began deep inside his temporal lobes. During the operation, he removed large portions of Henry's hippocampus, as well as surrounding brain tissue from both temporal lobes. Unfortunately for Henry, the vital importance of the hippocampus for making new memories was unknown at that time. Following surgery, Henry could not recognize his caregivers, he couldn't remember conversations or even find his way to the bathroom. He experienced profound anterograde amnesia meaning that he was unable to produce new episodic memories for the rest of his life. Think for a moment, what life must have been like for Henry. You're 27 years old and you will never make a new friend, never remember any movie that you watch or any book that you read. You will never consciously remember any new experience. This became Henry's life for the next 55 years. Neuroscientist Suzanne Corkin who studied Henry for many years found that Henry was aware of his limited memory. Do you know what you did yesterday? No I don't. How about this morning? I don't even remember that. What do you think you'll do tomorrow? Whatever's beneficial. He could remember personal experiences from before his operation, but as this conversation shows, events occurring after his operation were rapidly forgotten. What memory systems were affected by this operation? Henry's working memory was largely unimpaired. He could still carry on a conversation if you talked about things he already knew. He retained his knowledge of world events and his large vocabulary from before his operation. And surprisingly, he acquired a few bits of semantic knowledge after his operation. Perhaps from watching countless hours of television, he knew about Elvis Presley, astronauts, and John Kennedy's assassination, although, he often mixed up details. Finally, Henry could learn a few procedural skills after his operation, such as how to fold and unfold a portable walker that he needed after falling on ice. Curiously, he learned how to use the walker, but he had no memory of slipping on the ice. Unable to produce new episodic memories, Henry required constant supervisory care. At first, he was cared for at home by his parents, later, by the staff and a nursing home. What did Henry make of his condition? Talking with science writer, Philip Hilts, Henry had some thoughts about why he had trouble remembering. Do you know why you have trouble remembering? Well possibly I had an operation and somehow the memory is gone. Is that worrisome? Well it isn't worrisome in a way to me, because i know that if they ever performed an operation on me, they'd learn from it, it would help others. Given his enormous loss, Henry's generous spirit should make us all pause. No film better captures the experience of profound anterograde amnesia than Christopher Nolan's Memento with Guy Pierce, Joe Patolliano and Carrie-Anne Moss. Memento not only portrays a man grappling with this memory disorder, it simulates his experience in viewers. In telling two stories at once, this dark tale of revenge provides viewers with a puzzle to solve. There's a primary story involving Leonard Shelby's hunt for his wife's killer that is told backward from end to beginning and there is a secondary story about how Sammy Jankis unknowingly killed his wife told from beginning to end. Why is Leonard's story told backward? By alternating the scenes of each story, we learn about Sammy from Leonard an untrustworthy narrator with anterograde amnesia, and we learn about Leonard by watching his story unfold in reverse. This reverse order, says film maker Christopher Nolan, puts viewers inside Leonard's head sharing his amnesia and confusion. Like Leonard, we are living in the present with no recollection of what came before. In effect, we viewers also have anterograde amnesia. >> Now, where was I? >> The other side of the bed was cold, she'd obviously been out of the bed for a while. >> Leonard's life changed one night when two intruders assaulted and murdered his wife. Awakened by the scuffle in the bathroom, Leonard rushed to his wife's aid, killed one intruder but was beaten by the other, suffering brain damage that left him with anterograde amnesia. That says Leonard is the last thing that he remembers. Seeking revenge for his wife's death, Leonard is aided by a corrupt cop named Teddy and a drug dealer's girlfriend named Natalie. Both take advantage of Leonard's amnesia by having him eliminate unsavoury characters. >> Over here. [NOISE] >> You don't remember saying that. >> Even Burt, a motel clerk takes advantage of Leonard by renting him several rooms at the same time knowing that he will not remember. As they talk, Leonard tries to explain his condition. >> Since my injury, I can't make new memories, everything fades. If we talk for too long, I'll forget how we started and next time I see you, I'm not going to remember this conversation. [LAUGH] I won't even know if I've met you before. [LAUGH] So if I seem a little strange or rude or something. I've told you this before haven't I? >> Yeah, I mean I don't mean to mess with you, but it's so weird. You don't remember me at all? >> No. >> We've talked a bunch of times. >> I'm sure we have. >> To retain new experiences, Leonard writes detailed notes, takes Polaroid pictures and has cryptic reminders such as “Remember Sammy Jankis” tattooed on his body, external substitutes for his damaged memory [MUSIC] I wasn't the one that got to her. >> I never said that Sammy was faking. [MUSIC] >> Sammy? >> Alone in his motel room, Leonard narrates Sammy's story. As an insurance investigator, Leonard met Sammy when his diabetic wife filed a medical claim for Sammy's anterograde amnesia. Leonard denied them coverage because he found no medical reason for Sammy's condition, but Sammy's wife suspecting her husband of faking, gave him the ultimate memory test. Knowing that Sammy would never harm her, she had him administer her insulin shots every few minutes thinking that he would surely stop. But unable to remember the injections, Sammy kept repeating them until his wife slipped into a coma and died. [MUSIC] Later, Teddy tells Leonard a different version. >> See, Sammy's wife came to me. >> Sammy didn't have a wife. >> Which version is correct? >> It was your wife who had diabetes. >> Did Sammy kill his wife with an insulin overdose or is this how Leonard's wife really died? >> Ouch. >> Leonard's memory may be correct. >> My wife wasn't diabetic. >> Or it could be a fabricated memory, designed to cover up his culpability and memory loss. Does Leonard have organic amnesia from a concussion, or functional amnesia linked to the killing of his wife? The film provides brief clues, but they may be nothing more than red herrings. The question of whether Sammy's story is actually Leonard's story may be unanswerable. Due to his amnesia, Sammy could not have told Leonard the details of his wife's death and Leonard would not have remembered killing his wife by an insulin overdose. In simulating amnesia by cleverly putting viewers inside Leonard's confused head, Memento is an irresistible amnesia film even though it's portrayal is unrealistic. >> I don't even know how long she's been gone. >> If Leonard suffered a major concussion, the last thing that he would remember would probably not be his wife's death. He would likely experience retrograde amnesia, at least for recent events. >> Somehow I just, I just know she's never going to come back to bed. [MUSIC] >> Even more egregious, Leonard frequently demonstrates new memory after his wife's death, in spite of his anterograde amnesia. While in bed with Natalie for example, he recalls her earlier conversation, locates a pen and writes on her photo. >> She has also lost someone. She will help you out of pity. He remembers the Jaguar that he took from her boyfriend and even where he parks it each night. Leonard's remembering is needed to keep the film moving, but it passes unnoticed because it is so easy to take memory for granted, something that Henry Molaison could never do. Henry Molaison never recovered his ability to make new episodic memories. His anterograde amnesia was permanent, but other people sometimes show recovery providing their hippocampus is undamaged. Recovery from anterograde amnesia can occur, although, says neuropsychologist Barbara Wilson, it may only be partial after a lengthy period of rehabilitation. Thinking back to our first film on amnesia, Desperately Seeking Susan, why would a film suggest the recovery from amnesia could be rapid, requiring only a second knock to the head? This idea seems preposterous but several large surveys done in the United States, and Canada show that roughly 40% of those questioned believed that a second head knock can help people remember. Comedies are meant to be entertaining and need not be scientifically accurate, but where did this misinformation come from? Some films seem to have confused functional and organic amnesia. In Desperately Seeking Susan, Roberta only experiences retrograde amnesia after banging her head followed by rapidly recovering her lost memories after a second concussion. >> All right, play it that way. >> These memory loss and recovery characteristics occur with functional, not organic amnesia. Perhaps this inaccurate portrayal of concussion-based amnesia is based on the mistaken assumption that amnesia simply involves forgetting the past and functional and organic amnesia are two signs of the same coin. Therefore if re-experiencing an emotional trauma can produce rapid memory recovery in functional amnesia, then re-experiencing a traumatic blow to the head might do the same for organic amnesia. But facts tell us otherwise. A second concussion never produces recovery, it produces more brain damage. Amnesia is almost always more complex than it's depiction in film where people wander around confused while engaging in all sorts of adventures before usually recovering their memory by film's end. Amnesia can make for an entertaining story, but stories involving real amnesic patients, people such as Clive Wearing or Henry Molaison would be terribly depressing to watch. These memory impaired people do not run off seeking adventure and romance. Amnesia, you now know, can produce an anterograde and or retrograde impairment, it can be temporary or permanent, and it has different loss and recovery characteristics depending on it's organic or functional origin. I'll talk more about losing memory next time in my coverage of normal and pathological memory changes as we get older. [MUSIC]
