Mind fiction: Why your brain tells tall tales - being-human - 07 October 2006 - New Scientist
- Confabulation is not a disease condition. It appears to be a genetically programmed response in all human brains to "fill the gaps" in knowledge. We MUST know what is happening, where we are, why things are happening. - post by mbthorman
Mind fiction: Why your brain tells tall tales
- http://www.newscientist.com/channel/being-human/mg19225720.100;jsessionid=EFGGKOEJLAGP - post by mbthorman
- http://www.newscientist.com/channel/being-human/mg19225720.100;jsessionid=EFGGKOEJLAGP - post by mbthorman
- URL: http://www.newscientist.com/channel/being-human/mg19225720.100;jsessionid=EFGGKOEJLAGP - post by mbthorman
One of the last times I saw my grandmother in her nursing home she chatted cheerfully about her son, who was away studying at university. She spoke with complete conviction and considerable pride, despite seeming also to recognise that her only son - my father - sitting right beside me, was not far off retirement age. The impossibility of her tale caused her no apparent distress or confusion. Her story was lucid and complex. It was as though a perfectly plausible anecdote had been plucked from several decades earlier and woven into the void of her recent memory.
Many older people gradually develop amnesia about recent happenings while retaining a wealth of detail from their younger days. They may make up stories to cover their embarrassment about the blanks, and generally they know their memory is foggy. The kind of storytelling my grandmother did after a series of strokes is a little different.
Neurologists call it confabulation. It isn't fibbing, as there is no intent to deceive and people seem to believe what they are saying. Until fairly recently it was seen simply as a neurological deficiency - a sign of something gone wrong. Now, however, it has become apparent that healthy people confabulate too.
Children and many adults confabulate when pressed to talk about something they have no knowledge of, and people do it during and after hypnosis. This raises doubts about the accuracy of witness testimony (see "The unreliable witness").
In fact, we may all confabulate routinely as we try to rationalise decisions or justify opinions. Why do you love me? Why did you buy that outfit? Why did you choose that career? At the extreme, some experts argue that we can never be sure about what is actually real and so must confabulate all the time to try to make sense of the world around us.
- The question of distinguishing "self" from "non-self" arises here. Also, it appears that we make our decisions on a subconscious level and later "rationalize" those decisions in the conscious mind. Are there any other animals that confabulate? - post by mbthorman
Confabulation is clearly far more than a result of a deficit in our memory, says William Hirstein, a neurologist and philosopher at Elmhurst College in Chicago and author of a book on the subject entitled Brain Fiction (MIT Press, 2005)
Armin Schnider, a neurologist from the Cantonal University Hospital in Geneva, Switzerland, says that the vast majority of confabulations he has heard from his patients over the years relate directly to their earlier lives. One of his patients, a retired dentist, worried while in hospital that he was keeping his patients waiting. Another, an elderly woman, talked regularly about her baby in the present tense. Most of these patients had damage to the temporal lobes of the brain, particularly the memory regions of the hippocampus, so it seemed likely that they had somehow lost the ability to make new memories and were retrieving old ones instead. The intriguing thing was that they didn't realise these memories were old - they seemed convinced by their stories, and sometimes even acted on them. So Schnider decided to study their memory in more detail.
He found that his patients certainly had poor recall. If asked to learn a list of words, half an hour later they would be unable to name any of them. But was the problem to do with making new memories or accessing them later? To find out, he showed each person a series of pictures and asked them to point out any that appeared twice. Some confabulating patients and all amnesiac non-confabulators failed the task, unable to learn new information as the images flashed past. Often, though, even profound confabulators could do the task well.
Reality check
The most revealing thing about the experiment emerged when Schnider repeated it an hour later with the same images presented in a different order and with different ones repeated. The subjects were asked only to report repeats in this particular viewing, forgetting the earlier run - again, normally a very easy task. The scores of amnesiac non-confabulators were identical to the first session, but confabulators all performed terribly this second time around. Often they said they had seen a picture earlier in the run, when actually it was one they had seen an hour before. So the problem for people who confabulate is not necessarily that they can't make new memories, but that they confuse memory and present reality. "They se
So the problem for people who confabulate is not necessarily that they can't make new memories, but that they confuse memory and present reality. "They seem unable to suppress memories irrelevant to ongoing reality," says Schnider.
- There may be a relationship between this phenomenum and the inability to differentiate dreams from reality! - post by mbthorman
The decision process happens subconsciously, too early for awareness. Our brain sorts fact from fiction well before we know our own thoughts, he concludes.
- Shoot first and ask questions later? Is this a basic human trait? - post by mbthorman
One rare condition can make people confabulate even more elaborate tales. Capgras's syndrome sometimes affects people after a stroke, and can leave them believing that their loved ones have been substituted by identical-looking impostors, so they make up stories of alien abduction and conspiracy in an attempt to explain this crazy situation. In similarly strange conditions people may lose the ability to recognise themselves in the mirror, or may even believe they or another person are dead, despite all evidence to the contrary. In each instance, the affected person confabulates to explain the weirdness, oblivious to the absurdity.
- Disease conditions of the brain help us to understand more about how a normal brain functions. If it can happen in a diseased condition, the structure for the phenomenum is already in place in the brain. The differences are often a matter of inability to suppress or an inability to retrieve the phenomena. - post by mbthorman
What all these conditions have in common is an apparent discrepancy between the patient's internal knowledge or feelings and the external information they are getting from what they see. In all these cases "confabulation is a knowledge problem", says Hirstein. Whether it is a lost memory, emotional response or body image, if the knowledge isn't there, something fills the gap.
Helping to plug that gap may well be a part of the brain called the orbitofrontal cortex, which lies in the frontal lobes behind the eye sockets. The OFC is best known as part of the brain's reward system, which guides us to do pleasurable things or seek what we need, but Hirstein and Schnider suggest that the system has an even more basic role. It and other frontal brain regions are busy monitoring all the information generated by our senses, memory and imagination, suppressing what is not needed and sorting out what is real and relevant.
According to Morten Kringelbach, a neuroscientist at the University of Oxford who studies pleasure, reward and the role of the OFC, this tracking of ongoing reality allows us to rate everything subjectively to help us work out our priorities and preferences.
People who confabulate may have damage to parts of the OFC itself that means it doesn't receive all the information, or perhaps doesn't rate that information properly. Or they may have damage to connected parts of the brain, such as memory regions, which means the OFC doesn't receive sufficient information on which to work. Either way, when the information the OFC receives is incomplete or contradictory, it may work overtime to try and make things fit. The result could well be fiction.
Kringelbach goes even further. He suspects that confabulation is not just something people do when the system goes wrong. We may all do it routinely. Children need little encouragement to make up stories when asked to talk about something they know little about. Adults, too, can be persuaded to confabulate, as Timothy Wilson of the University of Virginia in Charlottesville and his colleague Richard Nisbett have shown. They laid out a display of four identical items of clothing and asked people to pick which they thought was the best quality. It is known that people tend to subconsciously prefer the rightmost object in a sequence if given no other choice criteria, and sure enough about four out of five participants did favour the garment on the right. Yet when asked why they made the choice they did, nobody gave position as a reason. It was always about the fineness of the weave, richer colour or superior texture. This suggests that while we may make our decisions subconsciously, we rationalise them in our consciousness, and the way we do so may be pure fiction, or confabulation.
Even when we think we are making rational choices and decisions, this may be illusory too. The intriguing possibility is that we simply do not have access to all of the unconscious information on which we base our decisions, so we create fictions upon which to rationalise them, says Kringelbach. That may well be a good thing, he adds. If we were aware of how we made every choice we would never get anything done - we cannot hold that much information in our consciousness. Wilson backs up this idea with some numbers: he says our senses may take in more than 11 million pieces of information each second, whereas even the most liberal estimates suggest that we are conscious of just 40 of these.
Nevertheless it is an unsettling thought that perhaps all our conscious mind ever does is dream up stories in an attempt to make sense of our world. "The possibility is left open that in the most extreme case all of the people may confabulate all of the time," says Hall.
- Yes, no doubt about it! In my work with brain damaged and emotionally ill people, I noticed that many were able to access that kind of information which is stored in the subconscious yet not available ordinarily in the waking state. This may well explain why we have dreams which help us to resolve problems or have "clairvoyance" or even "prescience." We pick up all this information and store it, but the conscious mind ignores most of it. During the dream state when the subconscious seems to have access to the conscious in some manner, the bits and pieces of information overlooked by the conscious mind, come together - to give us insight. Suddenly we have a dream in which we know someone we know is in love and about to get married. That person has told us nothing to the effect. Yet many subtle signals are given unconsciously be the person we dream about and these are picked up by the subconscious mind. Body language, facial expressions, and even the choice of words you to describe something totally unreelated are all clues. We may have even picked up a bit of a telephone conversation while passing a room and never been aware of it consciously. So when someone is particularly tuned into his or her dreams and makes a clairvoyant or predictive declaration, it might seem like magic, withcraft, or a sixth sense to others more successful in maintaining the divide between reality (conscious awareness) and confabulation or dream states (subconscious awareness). - post by mbthorman
The unreliable witness
Our tendency to confabulate - to believe a fictitious story or memory - is a serious concern when it comes to trusting an eyewitness.
Another controversial forensic technique is hypnosis. Its reliability was tested experimentally in the 1980s by psychologist Jane Dywan of Brock University in Ontario, Canada, at a time when hypnosis was increasingly being used, with little opposition, to "refresh" eyewitness memory. She showed people pictures and then tested their recall over the following days. After a week, she hypnotised the same people and asked them again what they could remember. They all "recalled" more, but almost all the newly volunteered information was wrong.
Dywan says that hypnosis increases the focus of our attention and so increases the vividness and the ease with which information comes to mind. This may give us the sense of confident familiarity for false memories that we would normally only get with true ones. Hypnosis seems to interfere with our ability to judge what is real and what is not. Combine this confidence with increased recall, and you have set up a very dangerous situation, she says.
- People seem more willing to accept hypnosis (which has been medically approved, so to speak) than they are to accept the so-called psychic phenomena. Under hypnosis, though, a person may develop a "confabulation" which is then given positive reinforcemen by virtue of the fact that they confabulated under a medically approved technique. Many people know that something bad happened to them at an earlier time, but have successfully blocked the conscious recall of the events. When "given permission" to seek the event in the subconscious mind, they may "mix-up" true memories with fleeting thoughts, movies, other people's tales, and so forth. They create a reality which did not exist exactly as they recall it, but which seems "right" to them as a way of explaining the emotional consequences of the true event. They have been abused sexually by someone in the past, for example. But the kind of abuse and the abuser may not be true to reality when they recall it later in a dream-like state in which they have allowwed the barriers between the conscious and the subconscious to break down. But those newly created conscious memories become very real to them. Once created and accepted, these new memories are vehemently defended. A person must have confidence in what they perceive as reality in order to be comfortable. However horrible the newly created memory is, it is less horrible than the idea that what we KNOW as fact is not fact. Our sense of self is at stake. - post by mbthorman
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