While repetition enhances the factual content of memories, it can reduce the amount of detail stored with those memories and may even lead to false memories, a new study has found.
University of California - Irvine neurobiologists Zachariah Reagh and Michael Yassa have found that with repeated recall, nuanced aspects may fade away.
In the study, student participants were asked to look at pictures either once or three times. They were then tested on their memories of those images.
The researchers found that multiple views increased factual recall but actually hindered subjects' ability to reject similar "imposter" pictures.
This suggests that the details of those memories may have been shaken loose by repetition.
This discovery supports Reagh's and Yassa's Competitive Trace Theory - published last year - which posits that the details of a memory become more subjective the more they're recalled and can compete with bits of other similar memories.
The scientists hypothesise that this may even lead to false memories, akin to a brain version of the telephone game.
Yassa, an assistant professor of neurobiology & behaviour, said that these findings do not discredit the practice of repetitive learning.
However, he noted, pure repetition alone has limitations. For a more enriching and lasting learning experience through which nuance and detail are readily recalled, other memory techniques should be used to complement repetition.