Why do we forget? We forget because of our inability to retrieve a memory. We forget bec­ause, as we create a new memory, old memory begins to fade and disappear. We forget because of the competition between stored memories; similar information causes greater competition. Often an old memory makes it difficult to remember a new memory. It also happens that our previously lear­ned experience gets hampered by our new experience. We forget because of ‘encoding failures’; failure prevents the information from entering our memory space. We commonly experience temporary blocking of stored information. For example, we often find difficulty in recalling the name of a familiar face. Unknowingly or unconsciously, we often ‘edit’ or ‘rewrite’ our past experiences. Such memory distortions are due to the influence of our current knowledge and beliefs. For example, people displeased with romantic relationships tend to have a disproportionately negative take on past states of relationships. Often, we work act­ively to erase some memories. Our efforts to forget often boomerang. Our efforts to nullify those memories make them stick stronger. Conscious forgetting often doesn’t work. We become tragic prisoners of memory. Often our forgetfulness is deliberate. Often memory’s vices become its virtues. “These mind bugs are the occasional result of the normally efficient operation of the human memory system,” says Daniel Schacter.

Our memories range from profound to the most trivial. Rem­embering an experience, say the psychologists is influenced by the cognitive operations that are used during the initial encoding of that experience. Semantic memory is unrelated to specific experiences. Neurobiologists say that “semantic processing leads to superior memorability relative to non semantic processing”. Func­tional neuroi­maging studies have found an association of the left prefrontal cortex in verbal encoding; left prefrontal activation is greater during semantic relative to non semantic encoding. We become more forgetful when semantic encoding operations are disrupted.

We possess both short-term and long-term memories. Our short-term working memory reflects our current thinking; it provides us sharp details about a few things. Our long-term memory is a culmination of thoughts and experiences gained over a long time. Our long-term memory, though it can hold many things, the details are often fuzzy. What we remember is the gist of what happened, details are often missing. There is another view, and it says that our long-term memories are not as fuzzy as we think they are. The studies by neuroscientist Timothy Brady indicate the massive storage ability of long-term memories. He observed that these memories could also hold the detailed and precise form of information. Edward Vogel and Trafton Drew say that the brain contains information about different events and objects, but we can’t always find that information when we want it. We can describe an object very precisely when we see it. Write Vogel and Drew, “If we’re in a toy store and are trying to remember what it was that our son wanted for his birthday, we need to be able to voluntarily search our memory for the right answer — without being prompted by a visual reminder.” It seems our ‘voluntary searching mechanism’ is prone to interference and forgetfulness.