A few years ago, the actor Alan Alda visited a group of memory researchers at the University of California, Irvine, for a TV show he was making.  During a picnic lunch, one of the scientists offered Alda a hard-boiled egg.  He turned it down, explaining that as a child he had made himself sick eating too many eggs.  In fact, this had never happened, yet Alda believed it was real.  How so?  The egg incident was a false memory planted by one of UC Irvine's researchers, Elizabeth Loftus.  Before the visit, Loftus had sent Alda a questionnaire about his food preferences and personality.  She later told him that a computer analysis of his answers had revealed some facts about his childhood, including that he once made himself sick eating too many eggs.  There was no such analysis but it was enough to convince Alda.

Your memory may feel like a reliable record of the past, but it is not.  Loftus has spent the past 30 years studying the ease with which we can form "memories" of nonexistent events.  She has convinced countless people that they have seen or done things when they haven't — even quite extreme events such as being attacked by animals or almost drowning.  Her work has revealed much about how our brains form and retain memories.

Following is a thought experiment demonstrating how easy it is to form a false memory.

Read the following two lists of words and, after pausing for a few minutes, press the button to display the third list.  Put a check mark next to each word in the third list that appeared in either of the first two lists.  When you are done, click the button to see how many words you got right.

List 1
apple,  vegetable,  orange,  kiwi,  citrus,  ripe,  pear,  banana,  berry,  cherry,  basket,  juice,  salad,  bowl,  cocktail

List 2
web,  insect,  bug,  fright,  fly,  arachnid,  crawl,  tarantula,  poison,  bite,  creepy,  animal,  ugly,  feelers,  small