We all have memories that we would prefer to not remember or have memories of moments that had been forgotten happened until something triggered that memory to be conscious.  But what causes this to happen?  We could take PTSD for example, a fine case where memories that are so vivid and sensory driven, just as easily manifested, be so actively forgotten? Like we learned in class, the brain takes in sensory information that we don’t always pay attention to.  We may engage in experiences that encourage the retention of the memory but just as actively as the mind can take in information, it can also ignore information.  Giving rise to the theory that the brain has multiple processes that go into memory, both long term and short term. I wanted to know (a) if these cues that we use in our everyday lives to help us recollect memories, have the same function in a suppressed memory, (b) what happens in the brain when memories are repressed, and (c) what happens to these memories when they surface after being repressed?


(a) One study done on children and adults to show that the brain has the ability to actively suppress information/memories to limit unwanted material in their consciousness.  This is caused by the part of the brain increasing in activation (lateral PFC, in charge of short term and working memory) and had reduced activity of memory-related structures (Medial TL) including the hippocampus, the part of the brain that runs much of the translation for long term memory.  This results in less declarative memories, one type of long term memory that contains facts and events that help recall (or “declare”) memories.   This also shows that the brain has active control over memory processes, specifically declarative long term memory along with filtering and a number of processes.

(b) Another experiment was done where they had participants who were asked to memorize a list of word-picture pairs and were asked recall each pair and their brain function was recorded.  After, they were told to do a similar process except this time they were to not think of the picture that corresponded with the word.  A fMRI scan was done on each subject to monitor brain activity.  They found that the brain had an especially hard time suppressing the older pictures learned versus the newer set of pictures they were shown.  This showed psychologist that visual memory in long term memory was harder to repress than working/ short term memory.  They also found that over time, it was easier and easier for the subject to repress the visual memory of the word, i.e. higher subliminal priming.

The cognitive approach that was in the articles I read were what parts of the brain were used and what memory processes were inhibited in the active suppression period.  So far, the studies have shown that long term memory is still intact with the memories but is stored differently, hinting to maybe a different encoding system or connections as discussed in class.  We know that the brain has different stages of memory and different types of memory.  We also learned that certain memories have connections that help with quicker, better long term processing after being presented with a cue.

memory-block-628x300(c) But what happens to these old repressed memories that surface after years of repression? Studies have shown that a number of things can happen to these memories.  In the case of trauma, like PTSD and abuse victims, even more variations were seen.  Memories that are being repressed, especially those that follow trauma are extremely malleable.  They had been seen to increase in intensity to the complete “termination” of the memory (seen mainly in children of a young age).

Psychoanalysis and cognitive psychologist have been working hand in hand on more studies that ask questions like where did the memory go?  What mental processes keep the memories suppressed and are these processes that allow these memories to seep through when memories surface if they ever do?  I was interested in these articles because we talked about memory in class and I wondered how Brian Williams could just “make up” a memory and I found these articles that talked about the opposite, not making up memories but forgetting them.  I hope to find more articles in this topic to further my understanding on memory suppression and its cognitive processes.