In this demonstration, one person was shown an ambiguous drawing (in the top left of the picture). This person was then asked to try to reproduce the drawing from memory. Because we like to classify things into categories rather than dealing with unknown objects (3), the person who was trying to draw the ambiguous original drawing from memory drew it to look kind of like an owl. Their drawing was then shown to another person, who again was asked to reproduce it from memory, and this cycle continued. As you can see, the drawing gradually evolved from an owl to a cat! Each time someone re-drew the picture from memory, they changed it, and eventually even the animal itself changed.

The fact that memory is reconstructive necessarily means that memory is not objective. Our memories are a lot more approximate and less accurate than you might like to believe. In particular, we are prone to having “false” memories – these are memories of things that never happened, or happened quite differently to the way we remember them (4). In addition, since we see the world through our own unique filter – our world view – we tend to remember things in a way that fits our “schema”, or pre-determined categorizations of the world and how objects and people behave (5).

The idea that we can have memories that are “false” gained credibility starting in the 1970s and was a topic of hot debate for decades after that. The leader of this field is Elizabeth Loftus, who demonstrated that eyewitness testimony can be inadvertently affected by information encountered after the event (“misleading post-event information”). Imagine you are a witness to a crime. It was dark, but you think you saw a tall man in a mask, holding something in his hand. After this event, you are questioned repeatedly by the police, and you also discuss the event over and over with your friend who was standing next to you when this happened.