Mind & Body

Cryptomnesia Can Make You Plagiarize Without Realizing It

Have you ever started telling someone a story, only to realize they were the one who told you about it? What about reading an old diary or school essay that contains an idea you thought you just came up with last week? These are all examples of cryptomnesia, the act of recalling a memory but misidentifying it as a novel thought. When it comes up in a social situation, it's usually just an annoying quirk, but this phenomenon has led to real consequences for many high-profile figures.

Ideas vs. Memories

The concept of cryptomnesia isn't new — the word itself was coined around the turn of the 20th century, although at the time it was used to refer to the kinds of "hidden" memories that could only be recalled during hypnosis or some other state of altered consciousness. By the 1960s, researchers were using it to mean the kinds of old memories you recall during normal consciousness that you identify as new thoughts. It's not surprising that the phenomenon got a lot of research attention, seeing as the very academics writing about it were at risk of doing it themselves and being accused of plagiarism.

For a study published in 1989, Alan S. Brown and Dana R. Murphy from Southern Methodist University examined the idea in the laboratory. They split students into groups of four and had them take turns coming up with examples in a given category, like animals, sports, clothing, or musical instruments. The only catch: Every example had to be new. They couldn't repeat what someone else had said.

They sat to next each other and went down the line, each person giving one example over two turns, then switching up their seating order for three more categories. Next, they had to write down the examples they themselves came up with in the group exercise, then come up with four new examples for each category that nobody else had mentioned.

During the group exercise, more than 40 percent of the students repeated something that someone else had said without realizing it. The written exercise was even worse: 75 percent of people wrote down someone else's example as one they had mentioned, and 70 percent of them wrote down someone else's example as a new example they came up with. According to the researchers, this shows that when you hear something said, you're more likely to plagiarize it in writing than you are in speech. As Ronald T. Kellogg concluded in "The Psychology of Writing," " ... writers may be especially susceptible to borrowing unknowingly ideas they have gained through lectures, discussions, and other forms of aural input ... Ideas that are expressed frequently — that are "in the air" — are especially open to borrowing."

Who Knows Where or When

Knowing this, it makes many high-profile accusations of plagiarism a little more understandable. In 1976, George Harrison was found guilty of "subconscious plagiarism" for his song "My Sweet Lord," which copied Ronnie Mack's "He's So Fine." In 1978, Alex Haley was sued for plagiarism in his seminal book "Roots," which he claimed was about his own family but included ideas from Harold Courtlander's book "The African." In 2012, science writer Jonah Lehrer was accused of self-plagiarism for reusing older content in several of his books. And in 2016, Led Zeppelin went to court after being accused of writing "Stairway to Heaven" with melodies lifted from a band they'd performed with.

No one knows whether these were cases of cryptomnesia or just garden-variety stealing, but it warrants a second guess. Memory is a tricky thing — all it takes is the right suggestion to plant a false memory, and even real memories are subject to distortion. Add that to that classic truism, "There's nothing new under the sun," and it makes you marvel at how people ever come up with new ideas at all.

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Learn more about how memory can fail you in "The Memory Illusion: Remembering, Forgetting, and the Science of False Memory" by Dr. Julia Shaw. We handpick reading recommendations we think you may like. If you choose to make a purchase, Curiosity will get a share of the sale.

Written by Ashley Hamer February 15, 2018

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