This is interesting, though it seems like a small difference:
In a series of experiments, a few hundred participants took a self-guided tour through the church. On the tour, the participants were supposed to take note of details like “the cruciform shape of the church” and make sure they checked out the bronze angels that “greet you from the massive entry doors.”
Some of these participants had iPods equipped with cameras and were instructed to take photos (either to print out later or to post on Facebook). Other participants went in empty-handed.
A week after the tour, the participants were given a surprise quiz, with questions about details they should have learned on the tour. In one arm of the study, those without a camera got around 7 out of 10 questions right. Those who had a camera scored closer to 6. That’s like going from a C to a D, a small but significant difference.
“Just taking photos in general was enough to decrease scores on a memory test,” says Emma Templeton, a Dartmouth psychological researcher who was a co-author of the study.