We take notes because we want to remember all kinds of stuff: A niece's birthday, the answer to a test question, what to buy at the grocery store, etc. etc.
But a new study published in the journal Memory & Cognition suggests that instead of enhancing our memory, writing stuff down actually makes us more forgetful because we know we can just look at our notes later.
In the study, researchers had participants play multiple rounds of Concentration (the game where you need to remember the identity and location of pairs of cards in order to match them). Half of the volunteers were allowed to take notes on the location of the cards before the game started, while the other half were just allowed to study the cards without writing anything down.
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The researchers then pulled a fast-one on the note-takers; they unexpectedly took away their notes before the game kicked-off.
Without their scribblings, the note-takers performed significantly worse than the participants who had studied the layout of the cards without writing anything down, leading the researchers to speculate that "participants adopted an intentional-forgetting strategy when using notes to store certain types of information."
In other words, the notes acted like a crutch; the note-takers knew they'd have reference material later, so their brains weren't working very hard to remember the exact location of the cards as they were revealed initially.
This ties back to a series of three experiments recently published in Psychological Science, where participants, all college students, were divided in half; one group was instructed to attend lectures and take notes by hand on paper and the other was told to type up their notes on laptops.
While the students who used their laptops took more detailed notes, often producing near verbatim transcripts of the lecture, when tested on conceptual understanding of the material they performed worse than their pen-and-paper compatriots.
"It appears that students who use laptops can take notes in a fairly mindless, rote fashion, with little analysis or synthesis by the brain," the authors wrote. "This kind of shallow transcription fails to promote a meaningful understanding or application of the information."
The takeaway, then: When your brain knows it can get away with drifting off because, you know, you have notes (!) it will do exactly that. And the more detailed (or, perhaps more accurately, transcribe-y) your notes, the more likely your brain is too wander off as you're taking them.
Which isn't to say, don't write stuff down. Take notes! Just don't lose them. Because your brain will likely need a refresher.