In the United States, today is celebrated as Memorial Day. It is a federal holiday for remembering the people who died while serving in the country’s armed forces. The holiday originated as Decoration Day after the American Civil War in 1868, when the Grand Army of the Republic established it as a time for the nation to decorate the graves of the Union war dead with flowers. Memorial Day eventually extended to honor all Americans who died while in military service. 

Many people visit cemeteries for all their passed loved ones regardless of whether they had served in the military. Memorial Day has become a day of remembering for many. But what is a memory?

Memories are more than a fond recounting of a person or experience. Memories are a neurological function. What we usually think of as memory in day-to-day usage is long-term memory. There are also short-term and sensory memory processes, which must be worked through before a long-term memory can be established.

The different types of memory each have their own particular modes of operation, but they all cooperate in the process of memorization.

One fundamental distinction has been made between long-term memory and short-term or working memory. Working memory is limited in capacity. It is capable of holding only about seven recognizable pieces of information for short periods of time,  i.e., about 20 to 30 seconds, without rehearsal. With some rehearsal, information can be maintained in working memory indefinitely.

In contrast, long-term memory appears to be virtually unlimited in capacity, and capable of storing the experiences, factual knowledge and skills over an entire lifetime.

Long-term memory can be broken down even further. Declarative memory refers to knowledge of episodes and facts that can be consciously recalled and related by the rememberer. It has been characterized as “knowing that” and includes such things as memory for the words on a recently presented list and knowledge that a cat is an animal.

Procedural memory is described as “knowing how” and pertains to an unconscious form of remembering that is expressed only through the performance of the specific operations comprising a particular task. The use of procedural memory is indicated by the performance of a newly acquired motor, perceptual, or cognitive skills.

Declarative memory can be further divided into episodic and semantic forms. Episodic memory refers to information that is remembered within a particular temporal and/or spatial context, like what you just ate for breakfast.

Semantic memory refers to one’s fund of general knowledge that is not dependent upon contextual cues for its retrieval. For example, asking how many feet are in a yard, the name of the first president of the United Sates, or the capital of California would all involve retrieval from semantic memory.

Obviously this is a high level peek into memory functions, but an interesting one. Memory is important on a personal level – just ask any student taking a test – and also for the future. Without remembering the past, we can’t improve the future.

“Without memory, there is no culture. Without memory, there would be no civilization, no society, no future.” – Elie Wiesel

Melody K. Smith

Sponsored by Access Innovations, the world leader in thesaurus, ontology, and taxonomy creation and metadata application.