When the event is subsequently recalled, the brain could use these markers as handy reference points for recreating the neural firing pattern of the original experience. The brain is not a computer, Damasio argues, so recall is not simply a matter of clicking the proper icon to call up the desired document from the brain's hard disk. Memories must literally be re-membered, put together again from pieces found in various parts of the brain. Memory depends on several brain systems working in concert across many levels of neural organization. Fortunately for most of us, the neural organization for memory in our brains is not nearly as implacable as that of Funes.
Memory is, in fact, a notoriously faulty and unreliable faculty.
We tend to perceive and remember only what we consider novel or important. The rest is indiscriminately dumped and forgotten. We have such selective recollection, Damasio suggests, because memories were developed more to predict the future than to retrieve the past. For that purpose, a few key perceptions are enough. Spot a twisted shape in the water and you jump, even though closer examination reveals it to be only a submerged stick and not a poisonous snake.