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How reliable is our memory for our own previous intentions?

Nearly six hundred undergrads answered open-ended questions about why they’d purchased, downloaded or copied their most recently acquired album (the vast majority had acquired one within the last two weeks), and then they provided the same information again six months to a year later. The participants’ answers fell into five main categories: because they liked the artist, liked the music, liked a specific song or songs, someone had recommended the album, or they needed the album for a specific purpose.

The key finding was that only one in five participants gave a consistent reason or reasons at both time points. The researchers had anticipated that memory for some reasons might prove more durable over time than others, but this wasn’t the case. Overall, the most common form of change was simply to invent new reasons at the later time point. Sometimes participants also forgot reasons they’d mentioned earlier. Unsurprisingly perhaps, participants who recalled more reasons at the first time point tended to be more prone to forgetting reasons when quizzed again later. This was also true of participants who reported liking their CD more, perhaps because they’d felt less need to dwell on their motives at the time they acquired the album.

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