By Terence T. Gorski
February 13, 2012
There are a number of basic concepts that I needed to get my arms around to understand new research being done in the study of human memory. The first distinction is long-standing. I first learned about it in my undergraduate studies in psychology in 1970. This distinction involves:
(1) Short-term Memory: This is the temporary storage of memory that rapidly decays and does not get stored in long-term memory. It is believe that short-term memory is held in a number of interrelated sensory memory circuits in the brain. To move a memory from short-term to long-term memory requires one of two things: (a) a strong and value driven initial experience which is believed, on some level, to have long-term survival value; (b) a repetitive experience that occurs on a regular and frequent basis until it becomes habitual.
(2) Long-term Memory: Long-term memory seems to work much differently than I was taught in the early 1970’s. Then, I was taught that long-term memory is stored in a way that is much like a movie camera recording a film and that the tapes can be replayed. I was even taught that it was possible to “replay the tape” and notice things that happened that I wasn’t aware of at the time the memory was stored.
Over the years new research began suggesting that long-term memories are actually stored in interrelated and over-lapping brain circuits. The memories are stored in sensory memory. This means that each sensory component of the experience being registered at the time is stored in a separate circuit. The sensory circuits represented are visual, auditory, tactile and gustatory, as well as states of balance and imbalance. The memory is accessed and reconstructed in our mind by integrating sensory memory networks into a single memory. The conscious mind filters and prioritizes the details of the remembered experiences in accordance with perceived survival needs in the moment, core belief systems, and automatic goal oriented future planning. As a result even the most stable of memories will change each time they are recalled, because the memory recall is purposeful and meets the needs of the moment.
The next concepts have to do with HOW WE ACCESS OR RETRIEVE MEMORIES after they are coded and store in long-term memory. There are two primary types of memory retrieval:
(1) Associative Memory: Associative memory recall occurs when we encounter something we have experienced before and part of the inter-related neural network that codes the memory is activated in response. We may not have thought of something in years. Then we see a picture, hear a voice, or encounter an idea that activates the memory circuit which then delivers to us a rich memory that can be further refined and shaped by paying attention to it. This is always memory reconstruction rather that factual recall. Some of the accessed memories will be factually accurate; some will have resulted from suggestions or accommodations to new belief systems acquired since the remembered experience; and still others will be CONFLABULATED or totally imagined in order to fill holes or gaps in our memory to make it consistent and intelligible given out current situation or context. Associative memories cannot be consciously recalled in the absence of a memory cue or a reminder of some kind.
(2) Retentive Memory: Retentive memories are readily available for conscious recall any time we choose to think about them. Retentive memories provide us with a sense of personal history. They consist of milestone memories that organize our personal timelines and give the conscious context or rationale for our “here and now” behavior. In addition, they shape the choices that create future experience in accordance with our core beliefs. These memories can be RECALLED (by remembering accurately, factual core elements of the experience), ENRICHED (by adding new detail), IMPOVERISHED (by deleting details especially those that don’t follow the core logic of the memory), or DISTORTED (by changing the interpretation or meaning of the experience that is recalled). Retentive memories can be easily retrieved at will be allowed just as easily to retreat into the background of experience. An external cue or reminder is not needed since it is in associative memory. When the conscious focus is shifted from experiences stored in retentive memories, there is a sense of confidence or a lack of anxiety about our ability to recall it again, when we need to or choose to.
Memory Decay: Memories that are not accessed by the conscious mind on a regular basis tend to deteriorate or loose a sense of detail and eventually a sense of the exact core sequence of events that make the memory intelligible or easy to understand. If there is a sense of urgency to recall a deteriorated memory, most people confabulate or fill in the missing parts of the decayed memory. Most people, however, are confident they are accurately recalling the decayed memory and will store the memory as if it actually occurred the way it was remembered.
When dealing with TRAUMATIC MEMORY STORAGE the process of memory is different and corresponds to a deeper understanding of the symptoms of both Acute Stress Disorders and Post Traumatic Stress Disorders (PTSD).
Loftus, Elizabeth and Ketcham, Katherine, Witness for the Defense: The Accused, the Eyewitness and the Expert Who Puts Memory on Trial, St. Martin’s press, New York, New York, 1991 ON THE INTERNET: http://www.amazon.com/Witness-Defense-Accused-Eyewitness-Expert/dp/0312084552
Schacter, Daniel L., **The Seven Sins of Memory: How the Mind Forgets and Remembers** , Houghton Mifflin Company, New York, New York, 2002. ON THE INTERNET: http://www.amazon.com/Seven-Sins-Memory-Forgets-Remembers/dp/0618219196/ref=pd_vtp_b_6