Are these two functions equal?

Thinking how our brain functions while retrieving old memories, but not able to retrieve older memories not accessed for long time. Clearly something similar to LRU cache algorithm functions. But which of the following two methods would it be?

• Thinking how our brain functions while retrieving old memories, but not able to retrieve older memories not accessed for long time. Clearly something similar to LRU cache algorithm functions. But which of the following two methods would it be? 1. Is our memory really limited (obviously even if its limited, its after a really high scale space.)? Does it mean the very old unaccessed memories would be erased (or may be overwrited with a newly accessed memory)? 2. Is our memory unlimited, an infinite LRU stack (atleast limited enough to a scale that all footprints of events/memories over a man's lifetime wont fill it up)? So every thought that is left unrecovered, is because of our limitation to process through depths inside ourselves? So would we be able to recover everything if we have such a concentration to go into depths? Again, it might be a mix and match of both mechanisms how we might lose track of our old-and-unaccessed memories :) :) Complicated, yet amazing life it is. :) :) #RandomThoughts

• Answer:

  This theory of working of brain I read somewhere may answer your question. Before seeing how retrieval works lets see how memories are stored in first place. Storage: Inputs from our sensors get encoded ( no one has clearly explained the encoding algorithm yet ) This encoded memory gets stored as neural footprint i.e, Kind of a pattern. New connections may be made in the process. The strength of these connections and the uniqueness of the pattern determine the strength of the memory formed. Retrieval is a process where we try to recreate this pattern. If the memory is newly formed it is easy for us to recreate that pattern. However when new memories are stored new patterns get recorded which utilities same neurons. As long as we keep recalling a thing the connections remain strong and we don't forget that thing. When we stop recalling a memory new memories/patterns start forming over them and we gradually lose that memory/pattern. For some years they may remain as partial or vague memory and finally we permanently lose that memory ! It is essentially a LRU mechanism as you said ! But our brain has enough storage capacity to store every life event. The catch is you have to keep recalling them to retain them .