One of the strangest conversations I have witnessed happened
when I was at a party at a friend’s house several years ago. He was regaling me with a story about making
breakfast in high school and covering the dog with pancake mix. He got through the end of the story (which
was funnier than you might think) when his brother piped in. “Great story,” he said, “but that was me, not
you. You were on the sofa
watching.” The next 20 minutes devolved
into an argument over whose life it really was.
I had forgotten about that story until I read a paper in the
September, 2010 issue of Psychological
Science Isabel Lindner, Gerald Echterhoff, Patrick Davidson, and Matthias
Brand. They were interested in how
observing actions influences your memory for those actions.
Previous research has shown that if people imagine
performing an action, they can later believe that they did it. I know I have had this happen to me. I have thought about bringing the garbage can
to the street on the day when garbage is collected. Later, I am surprised that it isn’t out on
the street, because I have mis-remembered thinking about taking out the garbage
as actually taking it out.
These authors were interested in whether observing an action
can lead you to think later that you actually performed it. To test this possibility, they first had
people read about a variety of simple actions like shaking a bottle or tapping
with a pencil for 15 seconds. Some of
the actions they only read about, while others they read about and also
performed.
After a short break, people saw videos of other people
carrying out some actions they actually performed, some they just read about,
and some that were not a part of the first phase of the experiment at all.
Two weeks later, the participants were shown a list of
actions and were asked whether they had performed them in the first session of
the study.
Across three studies, people were consistently more likely
to believe that they had performed actions that they had only seen someone else
perform than actions they had not seen someone else perform. That is, watching someone else perform an
action led people to believe later that they themselves had performed the action. This finding held up even when participants
were told at the beginning of the study to pay careful attention to the actions
they performed.
In a particularly interesting condition, this finding was
observed even when participants were warned that people often mis-remember
actions they see other people perform as things they did themselves. Knowing about this effect does not make it go
away.
Why does this happen?
As I have written about previously in this blog, when you
see someone perform an action, you often adopt the goals of the people you are
watching. This phenomenon is called goal contagion. Goal contagion is useful in social groups,
because it can lead an entire group to want to work together. A side effect of this goal contagion, though,
is that you may later think you were more involved in an action than you
actually were. The most extreme version
of this effect is a false memory that you performed an action that you actually
did not.
Findings like this reinforce the point that our memories are
not designed to provide a truthful readout of the events of our lives. Memory is designed to help us act in the
future. Seeing an action performed gives
you some confidence that you understand how to perform the action
yourself. Your memory is really trying
to tell you that you understand how to perform an action.
For example, when I first bought a house, a wasp built a
nest in ceiling of my back porch. I went
to the local hardware store and bought a can of spray to take down the
nest. I was really worried about getting
stung. The sales guy at the hardware
store took me outside with a bottle and sprayed it to show me how it was
done. After that, I went home and did it
myself. Just seeing someone else do it
helped me to understand how to do it myself.
It is only because our culture cares a lot about exactly who
performed particular actions that this facet of memory is seen as an error
rather than a benefit.
