New research found the stronger a memory is first encoded, the easier it is for a person to notice subsequent changes and to integrate them into their updated understanding.

“The bigger the discrepancy is between a previous memory and what happens the next time,” Zacks said, “the stronger the signal is that you need to update your memory representation.”

Results of the study also suggested that in older adults, a weaker ability to discern that one event differs from a previous memory may be partially responsible for a decline in memory function.