Wednesday, July 31, 2013

What Does it Mean if Many of our Memories are False?

The vagaries of human memory are notorious. A friend insists you were at your 15th class reunion when you know it was your 10th. You distinctly remember that another friend was at your wedding, until she reminds you that you didn’t invite her. Or, more seriously, an eyewitness misidentifies the perpetrator of a terrible crime. Not only are false, or mistaken, memories common in normal life, researchers have found it relatively easy to generate false memories of words and images in human subjects.
This passage is from a New York Times article about research just published in the journal Science: false memories were successfully implanted in mice. 
What does it mean that it is common for our memories to be false?
When I was fourteen my parents divorced (the event was so traumatic I’ll admit to being a little fuzzy about my age). This was totally unexpected; my four siblings and I had no inkling that anything was amiss in our parent’s marriage. One night the whole family was called into the living room, and my father told us he’d decided to separate from my mother and was moving out that night. We talked for some time and then he left. I have a very strong memory that all my brothers and sisters cried, but I didn’t.
Years later at a family gathering we discussed that night. All my brothers and sisters were there, along with our mother. Everyone shared their memories and how this had affected their lives at the time. One thing was stunning: each one of us had the same false memory. Each one of us thought everyone else cried but he or she didn’t. Our mother told us that we all cried.
The fact that all of us believed we didn’t cry says reams about our family psychology. But the point here is that all of us had operated for years from a false memory that slanted our perception of a pivotal event in our lives.
The premise of We Are ALL Innocent by Reason of Insanity is that everyone is deluded about reality; we are all confused about what is true. Optical illusions are wonderful illustrations of how we don’t perceive sensory information accurately (see blog post). False memory research shows we don’t accurately remember what happens to us.
Our mind-generated reality is largely constructed from sensory input and memories; if both of these are faulty how can our reality be anything but false?
“Delusion” means a “fixed, false belief resistant to confrontation with actual facts.” Even after my mother had told me I cried that night, I was resistant to believing her because my false belief was so strong. It had been reinforced by years of remembering.

Elizabeth Loftus, a cognitive psychologist, has been researching memory for decades. In a 1997 Scientific American article, “Creating False Memories,” she wrote:
My own research into memory distortion goes back to the early 1970s, when I began studies of the “misinformation effect.” These studies show that when people who witness an event are later exposed to new and misleading information about it, their recollections often become distorted. In one example, participants viewed a simulated automobile accident at an intersection with a stop sign. After the viewing, half the participants received a suggestion that the traffic sign was a yield sign. When asked later what traffic sign they remembered seeing at the intersection, those who had been given the suggestion tended to claim that they had seen a yield sign. Those who had not received the phony information were much more accurate in their recollection of the traffic sign. 
My students and I have now conducted more than 200 experiments involving over 20,000 individuals that document how exposure to misinformation induces memory distortion. In these studies, people “recalled” a conspicuous barn in a bucolic scene that contained no buildings at all, broken glass and tape recorders that were not in the scenes they viewed, a white instead of a blue vehicle in a crime scene, and Minnie Mouse when they actually saw Mickey Mouse. Taken together, these studies show that misinformation can change an individual’s recollection in predictable and sometimes very powerful ways.
The “hindsight cognitive bias” is another source of false memories. Daniel Kahneman talks about this in his 2012 book Thinking Fast and Slow:
A general limitation of the human mind is its imperfect ability to reconstruct past states of knowledge, or beliefs that have changed. Once you adopt a new view of the world (or of any part of it), you immediately lose much of your ability to recall what you used to believe before your mind changed.
Mr. Kahneman discusses an experiment in which people were polled on a position on which they hadn’t completely made up their minds. After they heard arguments for and against that position they were polled again. Usually people’s beliefs were closer to either of the two positions than they had been before. But the most disturbing part of all was that the participants were unaware that their opinion had changed! And this was for a belief that the person had changed half an hour before!
Asked to reconstruct their former beliefs, people retrieve their current ones instead—an instance of substitution—and many cannot believe that they ever felt differently….our inability to reconstruct past beliefs will inevitably cause you to underestimate the extent to which you were surprised by past events. Baruch Fishhoff first demonstrated this ‘I-knew-it-all-along’ effect, or hindsight bias in 1972.
Mr. Fishhoff asked people to rate the probability of fifteen possible outcomes of Nixon’s trip to China and Russia that year. After the trips the same people were asked to recall the probability they had given to the different possibilities. People exaggerated their earlier estimate of the events that happened, and underestimated their estimate of the things that didn’t happen. In other words, their memory was skewed to “I was right.” Mr. Kahneman concludes:
The tendency to revise the history of one’s beliefs in light of what actually happened produces a robust cognitive illusion.
For the hundredth-anniversary of the Titanic sinking in 2012, James Cameron produced a film, “Titanic: The Final Word with James Cameron.” He integrated hundreds of hours of his underwater footage of the wreck with detailed schematic drawings of the ship to create, in his words, a new visualization of the sinking. In a promotional video for the film he tells his team:
“It’s a good drive-a-stake-into-the-ground kind of moment. For us to say, ‘Let’s get the history right.’ To me the exercise in making the movie…was about understanding history. What is history? History is this kind of consensus hallucination.” 
A team member says, “There are some who tell the story of the sinking as if it were yesterday, and others who have been telling the story over the years, and the story changes.”  
“And how much does the telling of the story become the memory, as opposed to the memory itself?” Cameron adds.
I have this experience about many memories of my early life. I now remember the telling of the story more clearly than the actual experience that makes up the memory, and I’ve at times had the disconcerting thought that maybe I’ve just made the story up. And, as the not-crying story shows, I did sometimes make the story up.
For me this is just one more reason for humility about what I know!

1 comment:

  1. Thanks again for an insightful post. Another affirmation for why I want to be more present with "what is" in my life, rather than depending on reconstructions from the past. Feels much more sane.