This post is based largely on portions of the fourth chapter in Elixir J. Sternberg’s Book “Neurologic and the Brain’s idea Rationale Behind Our Irrational Behavior.” The title of this post is the same as the title of Chapter 4. Regular readers of the health memory blog should know the answer to the question posed in the title. The answer is “yes.” Elizabeth Loftus and others have done extensive research in this area. They have a variety of methodologies for implanting false memories so that they are definitely believed. I saw an example of one of these experiments on the PBS program NOVA. In this case the research participants were convinced of a crime that they never had committed. To find previous posts on this topic enter “Loftus” into the search block of the healthy memory blog.
Sternberg begins the chapter with a quote from Gabriel Garcia Marquez that largely captures the workings of our memories. “He was still too young to know that the heart’s memory eliminates the bad and magnifies the good, and that thanks to artifice we manage to endure the burden of the past.”
A research group in Israel filmed a young woman, with no history of memory problems for two days straight. Except for the cameras they were ordinary days. At various intervals over the next few years she filled out questionnaires that tested her memories of those days. The researchers used fMRI while she was filling out these questionnaires. Over time the more distorted her memory became for the details. What was especially interesting was how her brain activity changed over time while filling out the recall questionnaires. As time passed and the memory errors accumulated, her memory appeared to be less endless reliant on the activity of the hippocampus. The fMRI revealed reduced activation there as her recollection became more distant. Other regions of the brain, including the medial prefrontal cortex and associated regions, became more and more active. The medial prefrontal cortex is associated with self-centered thinking. Her memory was accessing not simply a record from a neurological file, but a representation stored across multiple systems. Her memory drifted away from accurately recording the details of that time period and instead became focused on her.
“To a large extent, our memories define us. Our personal history forges our self-image and assembles our store of knowledge. When the unconscious system in the brain encodes our memories, it is shaping who we are. It doesn’t record our experiences impartially as a video camera would, because it focuses on our role in the story, on the aspects that we care about. At any given moment, there is a context of how we are feeling, our emotions at that instant, what we are expecting or dreading, and what that moment means to us. It is on that basis that the brain begins to compose its first draft.”
Three years after 9/11, two groups of New York City residents were enrolled in an experiment to learn how their emotions at the time of the attacks might have affected their memory. The first group of people who were in downtown Manhattan that day close to the World Trade Center, and who personally witnessed the events of that day, The second group consisted of people who were in midtown several miles away. As would be expected, the downtown group rated their memories as being more vivid, more complete, and more emotional instances that the midtown group did. And they had more confidence in the accuracy of their memories, but the neurological results revealed a different story.
The hippocampus is the area key to episodic memory, of which recalling 9/11 is a conspicuous example, but depending on the type of memory being accessed, other areas of the brain may be recruited to varying degrees. For example, the amygdala may be activated when the memory is of an emotional nature, and the posterior parahippocampal cortex will become more involved when the brain attempts to access the more meticulous spatial details surrounding the event. The members of the midtown group showed activation of the posterior parahippocampal cortex as they recalled the details of 9/11, but only trivial amygdala activity. It was just the opposite for the downtown group. They exhibited striking activity in the amygdala but not in the posterior parahippocampal cortex. This neuroimaging suggests that the downtown group recalled the events of the day for their emotional impact at the expense of remembering peripheral details. Studies have revealed that the more emotionally affected people are in recalling 9/11, the better they are at consistently describing the central events of what happened to them that day, but the worse they are at providing reliable description of the emotionally neutral details.
There is a technical difference between telling a lie and confabulation. A person telling a lie knows that he is telling a lie. However, a person confabulating is trying to make a coherent story where substantial memory loss has occurred. The chapter begins and ends with a man with both severe mental and addiction problems and a faulty memory. He continually tries to put together a coherent story from the scraps of memory he can access, because he does not want to admit that he does not know. Although his is a clinical case, we all work to make coherent stories from what memories we can find. The unconscious system takes a self-centered egocentric approach to construct good narratives.