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When we store events in our memories, we tag them with keywords. Was the rollercoaster ride exciting, or scary? Was the dip in the pool cold, or invigorating?
Then when we encounter a similar situation, we run a quick keyword search of our memory to help us interpret the new event. Whether you go on the rollercoaster or jump in the pool depends on how you tagged these experiences last time.
This gets more interesting when you consider that we all use different keywords. These keyword tags become part of our reality, and thus our "realities" differ.
Elizabeth Loftus and John Palmer showed this by forcing their own keyword tags onto subjects' memories. They had subjects watch video of a car crash and then asked them to estimate the cars' speeds. Each subject watched the same thing, but the sneaky experimenters phrased the question four slightly different ways: "1. About how fast were the cars going when they hit each other?; 2. About how fast were the cars going when they smashed each other?; 3. About how fast were the cars going when they collided with each other?; 4. About how fast were the cars going when they bumped into each other?; 5. About how fast were the cars going when they contacted with each other?"
And so they tagged subjects' memories with the keywords hit, smashed, collided, bumped, and contacted. Subjects' estimates when tagged with "smash" averaged nine mph faster than their estimates when tagged with "contact".
Even spookier, though, is that this tagging didn't just affect peoples' estimates about the crash; it seemed to change their memories of the event as well. A week later when Loftus and Palmer asked subjects if the crash had produced broken glass, those with memories tagged with "smashed" said yes more often than those whose memories had been tagged with "contacted". For, of course, a smash breaks glass while a contact doesn't.
Stay tuned for tomorrow's description of how to create false memories. And see below for a classic example of memory control from the scientific literature.
You will buy my new book, Brain Candy: Science, Paradoxes, Puzzles, Logic and Illogic to Nourish Your Neurons. You are free to go about your business. Move along.
