Most people cannot remember what they had for lunch the other day, or what the weather was like two weeks ago, or any number of small details about their daily lives. But for the handful of people with hyperthymesia, or “extreme autobiographical memory,” these details are clear and vibrant. An individual with hyperthymesia could recall any detail from any day of his life – say, what the weather was on October 21, 1976, or what they ate for lunch on December 8, 1987 – as long as they lived it, they remember it. 

Dr. Gregory House, the main character on television drama 'House, M.D.'It is an odd condition, which means it is perfect for a medical television drama. Kath Lingenfelter, supervising producer and writer for House, M.D., stumbled on the memory condition in an article for Wired Magazine. “I was fascinated by a life where you could not forget the past,” she recalled. This small piece of science became Lingenfelter’s inspiration for the House, M.D. episode “You Must Remember This,” in which a waitress with perfect autobiographical memory is treated by House’s team.

Hyperthymesia is not a disease, but rather a symptom of a symptom, in the episode. The end diagnosis for the waitress is McLeod neurocanthocytosis syndrome, a rare (less than 150 cases reported worldwide) genetic syndrome with multi-system symptoms, including neurological disorders like obsessive-compulsive disorder (OCD). That’s the key to connecting hyperthymesia with McLeod syndrome – individuals with extreme autobiographical memory often display signs of OCD. “It was trying to attribute one condition, the superior memory, as a symptom of a symptom in McLeod’s, basically suggesting OCD was the engine behind her great memory; she didn't have some rare gift, rather this syndrome made her compulsive with her memories,” explained Lingenfelter. 

But all of this was purely speculative science; Lingenfelter, a self-described “science groupie,” needed a storyline backed by science. “More than anything I was concerned with infuriating the scientific community with my suspicions. That it was going to be so far beyond the bounds of reality that we would be laughed off screen,” she explained. “I sent a desperate e-mail to Rick Loverd [Director of Development for The Exchange] and within minutes, he had the names of three doctors I could speak to who were more than willing to take my phone call and listen to my situation.”

The neuroscientists, John Mazziato (Department of Neurology at UCLA) and Gisele Petzinger (Department of Neurology at USC), gave Lingenfelter the “green light” on her “hyperthymesia as a symptom of OCD as a symptom of McLeod syndrome” scenario. “It couldn’t have been an easier dialogue,” said Lingenfelter. 

Mazziato and Petzinger also assisted the storyline by providing information on how to diagnose the patient. One of the hallmarks of House, M.D. is that the illness is hidden until House solves the medical riddle at the end of the show. McLeod syndrome is diagnosed through the presence of acanthocytes (spiked red blood cells). If House’s team ran a peripheral blood smear at the start of the episode, the mystery would be solved in the first 15 minutes. Since the syndrome is also related to the brain, Lingenfelter needed to keep House’s team (especially neurologist Foreman) away from the brain. “I asked [Mazziato and Petzinger], ‘If someone comes in with her symptoms, how can we avoid focusing on the brain? Would it be typical that they would do a blood smear as one of the early tests? Realistically, how would this patient be treated?” explained Lingenfelter. “They were full of ideas. I was in such a panic before I made those phone calls and after, it was such a weight off my mind. It was having answers I could trust instead of just me and Google.”

Acanthocytes, or spiked red blood cells, in a peripheral blood smear.Even though Lingenfelter wanted to be accurate, she needed to stretch some of the science to fit the storyline. For example, McLeod syndrome mostly affects males. Females with the syndrome are normally asymptomatic carriers – a detail that did not work for the episode’s symptomatic female character. Also, females with McLeod syndrome do not have acanthocytes, which were needed for the character to be diagnosed with the syndrome. But Mazziato and Petzinger did not blink an eye at less plausible science. “They were so willing to play along with the fiction. They said, ‘If what you’re trying to do can’t happen in the real world, let’s see how can we get it as close to plausible as possible,’” said Lingenfelter.

Plausible science was all Lingenfelter needed to feel confident about the science in her storyline. “It was like talking to a grown-up and having them say, ‘It’s going to be okay,’” she explained. Having those conversations gave me a lot more confidence about what I was doing and how the medicine was being handled.” The episode also benefited from a science integrity boost, Lingenfelter said. “When you can feel good about the science, it brings a level of integrity to the story that you’re telling.” 

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