Rather, the question is what kind of memories do infants form? One possibility is that they only have memory for events when you place them back in the same situation, which is why they can learn and remember things they have encountered before. For example, in 1999, memory researchers contacted a dozen students who had taken part in a memory test in which they saw fragments of pictures presented for one to three seconds to test if they could remember them. Even though they saw them only briefly, students could recognize the pictures. Not too amazing, you might say, until you discover that this memory test took place in 1999, seventeen years after the original study! The students were now full adults with busy lives and some could not even remember taking part in the original study back in 1982 at the University of Minnesota. Yet stored somewhere in their memory networks were traces of the original experience because they identified pictures that they could not remember having been shown.16
Even Clive Wearing seems to have this ability to learn, but he can’t remember that he has learned. It’s like unconscious knowledge. Both Clive and young babies may not have the ability to consciously recall or reflect upon previous experiences. In contrast, most of us can recall what we had for breakfast yesterday by actively reconstructing in our minds the events. That requires a different kind of memory that psychologists call ‘episodic’ – one that reflects the actual experience of remembering the episodes that punctuate our lives.17 Memories of these episodes are crucial for constructing the self story and those which are particularly personal are known as autobiographical memories – those events that we can recall in which we are the main player.18 One might be tempted to assume that our autobiographical memories are accurate recollections but, just like any memory, they are not like photographs or recordings. One of the greatest discoveries in psychology is that human memories are reconstructed and malleable. We do not have a recording of our own personal experiences in our head like some video archive. There are no microfilms in our memory banks.
Memories are constantly active – like a story being retold over and over again. Moreover, when we encounter related new experiences, we interpret them in terms of our existing memories, which in turn are transformed by the new experiences. We are constantly integrating the here and now into our past. Consider the following powerful demonstration. Read the following list of fifteen words and try to remember them as best you can. Take a couple of seconds on each word to memorize it well.
thread
pin
eye
sewing
sharp
point
prick
thimble
haystack
thorn
hurt
injection
syringe
cloth
knitting
Now turn to the end of the chapter and answer the questions to see how good your memory is. Most people fail this test19 and yet they are pretty sure that they got the right answer, which makes the effect all the more dramatic. How can most of us be so convinced and yet so wrong?
The neural networks encountered earlier show how all information is stored as a pattern of activation across networks of neurons. You falsely remember the occurrence of the word that was never presented because it was related in meaning to the other words in the list. In the neural networks that process language and meaning, the pattern representing the word you believe you encountered was triggered as part of the collateral activity of all the other words that were processed and encoded. When one considers that memory is constant neuronal updating, it is remarkable that we remember anything at all with good clarity.
In 1932, the British psychologist Sir Frederic Bartlett, one of the few psychologists ever to be knighted, demonstrated that memories are not exact copies of past events, but rather, are reconstructed – like stories.20 Similar to the game of Chinese Whispers, every time the story is told, and retold, it changes. In fact, completely false memories can be constructed simply by asking leading questions. In what are some of the most influential experiments in human psychology, Elizabeth Loftus demonstrated that if you show adults a video event of a car accident, and then ask them leading questions such as, ‘Did the white car jump the red light?’, adults correctly deny that there was a white car in the sequence.21 However, if several weeks pass and the adults are asked to recall the video, they are more likely to report seeing a white car jump the red light even though it was never in the video. The mere mention of a white car during the initial questioning has now become incorporated into their memory. The neural networks that encoded the memory have become contaminated with neural activations of networks designed to scrutinize the memory for the presence of white cars and red lights. Likewise, when children are told they were once lost in a shopping mall, they can give vivid recollections about the event even though this event never actually happened.22
Confabulations of memory are not restricted to the young and naive. Piaget used to describe the time when there was an attempt to abduct him as a young child.23 Years later, he had vivid memories of how his nanny fought off the would-be abductors. However, eventually racked by guilt, the nanny confessed that she had made the whole abduction story up so that Piaget’s parents would be indebted to her. Half the adults shown a doctored photograph of themselves as children taking a hot-air balloon ride recall the fictitious event and can describe it in detail.24 Even Elizabeth Loftus, the world’s greatest authority on false memories, is not immune to them.25 When she was only fourteen years old, Loftus’s mother drowned in a swimming pool. Thirty years later at a birthday party, Loftus’s uncle reminded her that she had found her mother’s body. Over the next couple of days, the lucid memories of that terrible moment came flooding back to haunt Loftus, except that these memories were false. Her uncle had made a mistake. Loftus had not discovered her mother’s body but rather it had been her aunt. Later, Loftus said, ‘The most horrifying idea is that what we believe with all our hearts is not necessarily the truth.’
Memory as a Compost Heap
We all know that we forget things but to discover that a recollection is completely fabricated is something else. It is shocking because it makes us question our own minds. If we all can vividly remember events that never happened then this undermines the reliability of memory and ultimately the reality of our self. This is because part of the self illusion is that we know our own minds and recognize our own memories. But we are often mistaken. The reason we find false memories so shocking is that most people do not understand how memory works. Psychologists Dan Simons and Chris Chabris recently surveyed 1,500 US adults and discovered fundamental misunderstandings held by the general public.26 About two out of three adults (63 per cent) thought that memory works like a video camera, recording experiences that can be played back later. Half of the respondents believed that once a memory was formed it was unchanged and reliable. These misconceptions have lead to comparison with other ways of storing information that evoke some notion of a permanent store. A common metaphor is to liken human memory to a vast library storing volumes of information, which is wrong. Human memory is neither like a computer hard drive nor a pre-industrial blank slate upon which experience writes a trace.