If you have gone through a tragic event in your life, like the death of someone close or a physical attack, you may want to take the raw and hurtful memories and bury them deep within your subconscious – until a time when you are able to deal with them.

Sigmund Freud, a trained neurologist, proposed in 1892 that suppression of memories is the “voluntary form of pushing painful and anxiety-provoking thoughts, memories, emotions, fantasies and desires out of awareness.” Suppression differs from repression in that when you suppress a memory it is because you are deliberately trying to stop thinking about it, whereas if you were to repress your memory you are unconsciously trying to keep any memory of the event from coming back to the surface and being recalled in the conscious.

An example of suppression would be if you wanted to tell your boss what you really thought of him, but you held back because you want to keep your job so you bury the thoughts deep within you. Your willpower took over and stopped you from saying something you may regret later. The impulse to tell him off may rear its ugly head in other ways, however, such as a nervous cough whenever the boss is around, or a careless slip of the tongue (Freudian slip). These “forgotten” thoughts and memories are not actually forgotten but just tucked away, yet they may influence other behaviors and thoughts.

An act of repression would be if you were physically assaulted and the event was so traumatic that you pushed any detail of the entire incident out of your mind and could not remember any of what happened. Your mind has built up a defense system to keep you from reliving the trauma over and over again.

Technical advances have allowed scientists to directly measure brain activity – like with the use of magnetic resonance imaging (MRI). With this technology they have been able to look into how our brains are able to take traumatic events and build up defenses that include suppression, repression and even disassociation of these memories. Whereby some scientists believe that suppressed memories are simply a psychoanalytical myth with no scientific support, data obtained from fMRI scans show otherwise.

Researchers at St. Andrews University in Scotland, carried out a “think/no-think” experiment to explore the brain basis of memory suppression. Twenty-four volunteers had to memorize 48 word pairs (for example, ordeal-roach or steam-train). While they were lying in a scanner, each was shown the first cue word and had to either recall the second, associated word (called the respond condition) or prevent it from entering consciousness (suppress condition). “Actively suppressing the matched word while lying in the scanner had the effect of reducing recall of the word afterward (as compared with the respond condition), said head of the study, Psychologist Michael C. Anderson. “This result is not just simple forgetting that occurs with the passage of time.”

The imaging data that Anderson and his colleagues collected found that the volunteers suppressed the words by recruiting parts of the brain involved in “executive control,” namely, areas in the prefrontal cortex, to disengage processing in sectors of the brain important for memory formation and retrieval, in particular the hippocampus.

These finding are noteworthy because earlier experiments have indicated that the amount  of activity in the hippocampus is proportional to memory recall—the stronger the activity, the higher the likelihood of remembering. A second interesting offshoot of this experiment was the finding that the brain is more active when avoiding the recall of a memory than during the recall itself. People suppress unwanted memories by exerting willful effort that can be tracked in the nervous system.

This is Ron White, two-time USA Memory Champion , memory training expert, and memory keynote speaker.




Scientific American – Defense Mechanisms: Neuroscience meets Psychoanalysis: http://www.scientificamerican.com/article.cfm?id=neuroscience-meets-psychoanalysis