The psychology of memory

Nutrition Health Review, Wntr, 1989

The Psychology of Memory

Memory is usually thought of as a "magic slate" that can be wiped to allow more writing upon it, but at the same time retains that which is written beneath.

Freud said that it solves the problem of combining two functions by dividing them between two separate but interrelated component parts or systems. In human memory, these two interrelated systems are known as short-term and long-term memory.

Before an event can be stored in memory, it must be experienced in some way by the brain. As information flows in from the senses, the brain retains the stimulus briefly. The image of a flower fleetingly registers on the retina when the eye is closed, the sound of thunder echoes in the brain -- mechanisms of the sensory register. The images are retained for no more than a few seconds -- long enough for the brain's perceptual systems to act upon them.

The register records tremendous amounts of information, but only a small amount filters into the short-term memory. Human attention has its limitations so some images vanish from awareness. But with short-term memory information is retained long enough for the mind to grasp, about a minute. Unless the individual makes an effort to remember an item, it disappears and does not filter into long-term memory. Rehearsing the information will usually help to retain it; so does memorization.

Short-term memory is usually more accurate. Long-term memory undergoes revision, interpretation and often a reforming that suits the individual's prejudices, beliefs, and wishes. "People remember the past as they prefer to believe it happened," is a truism of human nature.

Even the best memory is imperfect, changing shape and content over time. Ten people who witness an event may remember ten different versions. A person may combine actual recollections with suppositions and inferences to construct a resulting false memory.

Perhaps that is why childhood memories become more colorful, more glorious with passing time. The fabric of the past becomes a rich tapestry -- far more glorious than actuality.