The episodic engram transformed: Time reduces retrieval-related brain activity but correlates it with memory accuracy.

@article{Furman2012TheEE,
  title={The episodic engram transformed: Time reduces retrieval-related brain activity but correlates it with memory accuracy.},
  author={Orit Furman and Avi Mendelsohn and Yadin Dudai},
  journal={Learning \& memory},
  year={2012},
  volume={19 12},
  pages={
          575-87
        }
}
We took snapshots of human brain activity with fMRI during retrieval of realistic episodic memory over several months. Three groups of participants were scanned during a memory test either hours, weeks, or months after viewing a documentary movie. High recognition accuracy after hours decreased after weeks and remained at similar levels after months. In contrast, BOLD activity in a retrieval-related set of brain areas during correctly remembered events was similar after hours and weeks but… 

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