Sure it can, it's not about how long the human brain can retain information, it's about how much it uses what information. Any information it doesn't put to use for a long enough period of time, it will eventually 'discard.' So to speak. The brain reacts to what we use and what we don't, if we don't use something, in the earlier stages of our lifetime, it cuts off those functions in the brain... because it has so many functions available, it has to pick and choose which ones are important enough to keep, and it bases this off of what functions we use the most and the ones we seem to need the most, etc. In a way, it does the same thing with information, if it's there, and we're not using it for anything, then it's just taking up space, and the brain just sees it as more clutter that can be removed to free up space for new information. Just like with computers, you have a certain capacity on your hard drive, and when you want to add new data, but don't have the space for it, you must first delete something else. And the things we generally choose to delete, are things we do not use, or need. =)
