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?"