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severance payThe show, which imagines a world where a person's work and personal life are surgically separated, returns Friday for its long-awaited second season. While the concept of this gripping science fiction novel is far-fetched, it touches on a question that neuroscience has been trying to answer for decades: Can a person's mind really be split in two?

It's worth noting that "split-brain" patients have been around since the 1940s. To control epilepsy symptoms, these patients underwent surgery to separate the left and right hemispheres. Similar surgeries are still happening today.

Later studies of such surgeries showed that the separate hemispheres of split-brain patients could process information independently. This raises the unsettling possibility that the program is creating two separate minds within one brain.

in season 1 severance payIn "Haley R." (Britt Lorre), she experiences the conflict between an "introvert" (the side of her life that remembers work) and an "extrovert" (the side outside of work). Likewise, there is evidence of conflict between the two hemispheres in true split-brain patients.

When talking to a split-brain patient, you are typically communicating with the left hemisphere of the brain, which controls speech. However, some patients can communicate through their right hemisphere, such as writing or arranging Scrabble letters.

In one study, a young patient was asked what job he wanted in the future. His left brain chose an office job producing technical drawings. However, his right hemisphere arranged the letters to spell "car racer."

Split-brain patients also report "foreign hand syndrome," in which one of their hands is believed to move voluntarily. These observations suggest that two separate conscious "people" may coexist in a single brain and may have conflicting goals.

exist severance payHowever, both introverts and extroverts can use language. This suggests that the fictitious "dissociation procedure" must involve the dissociation of more complex brain networks.

A complex example of functional dissociation was described in Neal's 1994 case report. Neil is a teenage boy who has experienced many difficulties after developing a pineal gland tumor. One of the difficulties is a rare form of amnesia. This meant Neil was unable to recall the events of the day or report what he had learned at school. Although he could write, he could not read; although he could draw, he could not name objects.

Amazingly, Neil was able to keep up with his studies. Researchers became interested in how he completed his studies without remembering what he had learned. They asked him about a novel he was studying at school, Rosie's Cider Author: Laurie Lee. During the conversation, Neal couldn't remember anything about the book, not even its title. But when a researcher asked Neil to write down everything he could remember about the book, he wrote "bloodshot geraniums open cider with the dank peppery scent of rosy draneum" (sic so) and the smell of growing mushrooms”—all words relevant to the novel. Because Neil couldn't read, he had to ask the researchers: "What did I write?"