Recognition memory

Recognition memory, a subcategory of declarative memory, is the ability to recognize previously encountered events, objects, or people. When the previously experienced event is reexperienced, this environmental content is matched to stored memory representations, eliciting matching signals. As first established by psychology experiments in the 1970s, recognition memory for pictures is quite remarkable: humans can remember thousands of images at high accuracy after seeing each only once and only for a few seconds. Recognition memory can be subdivided into two component processes: recollection and familiarity, sometimes referred to as "remembering" and "knowing", respectively. Recollection is the retrieval of details associated with the previously experienced event. In contrast, familiarity is the feeling that the event was previously experienced, without recollection. Thus, the fundamental distinction between the two processes is that recollection is a slow, controlled search process, whereas familiarity is a fast, automatic process. Mandler's "Butcher-on-the-bus" example: Imagine taking a seat on a crowded bus. You look to your left and notice a man. Immediately, you are overcome with this sense that you've seen this man before, but you cannot remember who he is. This automatically elicited feeling is familiarity. While trying to remember who this man is, you begin retrieving specific details about your previous encounter. For example, you might remember that this man handed you a fine chop of meat in the grocery store. Or perhaps you remember him wearing an apron. This search process is recollection. The phenomenon of familiarity and recognition has long been described in books and poems. Within the field of Psychology, recognition memory was first alluded to by Wilhelm Wundt in his concept of know-againness or assimilation of a former memory image to a new one. The first formal attempt to describe recognition was by the English Doctor Arthur Wigan in his book Duality of the Mind.