Memory is fallible for everyone, at any age, experts say, partly because it just can’t store all the information we take in. That makes forgetting an important strategy, per the Washington Post. So how do you know whether confusion or a lapse in memory is indicative of a serious mental decline? “You don’t,” Dr. David Loewenstein, a cognitive neuroscience and aging expert, told the New York Times. Such a diagnosis is not based on forgetting when someone died; it requires a series of sophisticated and objective tests that assess different types of memory, language, executive function, problem so…