Consciousness is a Magic Trick - Dan Dennett
The first problem in understanding our own minds is giving up many of the things we think we know. Dan Dennett is a philosopher of consciousness whose talk for TED, which uses visual illusions as illustrations, shows how consciousness is a kind of magic trick cooked up by our brains.
It's a very simple message, but a vital one in understanding the mind. What Dennett explains so neatly is that it's natural to think we're experts on consciousness - and psychology - by virtue of being conscious ourselves and having access to our own thought processes. But actually we're none of us quite as informed about ourselves as we'd like to think.
» For more on the psychological version of this point, read this series on how the inner workings of our minds are hidden from us.
It's a very simple message, but a vital one in understanding the mind. What Dennett explains so neatly is that it's natural to think we're experts on consciousness - and psychology - by virtue of being conscious ourselves and having access to our own thought processes. But actually we're none of us quite as informed about ourselves as we'd like to think.
» For more on the psychological version of this point, read this series on how the inner workings of our minds are hidden from us.
False Memories Can Influence Behaviour
Participants avoided egg salad sandwiches after false memories of sickness were implanted.
Psychologists have found many processes that act like lenses, creating distorted memories of original events. These processes include things like cognitive dissonance, the consistency bias and misattribution. But what power do these distorted or false memories hold over the mind? How far are they able to weave themselves into the tapestry of our lives? In short: can false memories affect our everyday thought and behaviour?
According to the results of a new experiment reported in Psychological Science, false memories could have many and varied behavioural consequences: just like 'real' memories, they may well be able to reach forward to the present and dramatically change how we think and behave.
Implanting false memories
To investigate the power of false memories Dr Elke Geraerts and colleagues (Geraerts et al., 2008) first had to induce false memories in participants: in this case that egg salad made them feel sick.To achieve this, participants were invited to take part in a study they were told was about 'food and personality'. They answered a number of questions about food which were apparently to be entered into a computer programme to produce a profile of their early childhood experiences with food.
A week later two-thirds of the participants were told in this profile that they had got sick after eating egg salad at an early age, while the remainder - the control group - were not. The experimenters then had to check who had accepted this false memory as one of their own, and who had not. Using questionnaires they discovered that almost half of the experimental group had taken the bait and created a false memory while the rest were 'non-believers'. This demonstrates, once again, just how easy it is to induce false memories in some people.
Avoiding egg salad
The second stage of this experiment took place four months later when the participants were contacted by a different experimenter apparently about a different study - of course this was just a ruse. Participants were told this study was about people's preferences for different types of foods. A variety of different types of sandwiches and drinks were on offer for participants to test and rate, but most of these were a distraction as the experimenters were most interested in those egg salad sandwiches.After the participants had left they tallied up how many of each type of sandwich had been consumed. They found that those who had accepted the false memory about getting sick after eating egg salad sandwiches ate far fewer of these sandwiches than those in the control group or those who were 'non-believers'.
While the non-believers and control group ate, on average, about 0.4 egg salad sandwiches, the false memory group ate only about 0.1. They were certainly avoiding the egg salad as this pattern of consumption wasn't seen in any of the other types of sandwiches.
Re-imagining the past
What this study clearly shows is that not only is it possible to instil false memories in a significant minority of people, but that these false memories can have a marked effect on behaviour.Naturally this should make us wonder which of our preferences, attitudes, or phobias even, might be based on false recollections. Could that distaste for yellow peppers have stemmed from a false memory of getting sick after eating them? Or could that desire for a seaside home be built on childhood beach trips misremembered as enjoyable?
What this experiment underlines is the idea that the way we remember, interpret and, perhaps, re-imagine the past has a profound effect on how we think and behave in the present.
» Find out more about the 7 sins of memory.
[Image credit: ghirson]
Romantic Thoughts Increase Male Chivalry
While dreaming of his beloved a man easily slips into a daydream of himself clad in shining armour, riding his trusty white charger, sweeping to the rescue of a beautiful woman. In reality he may only be holding a door open or picking up the tab, but the feeling is the same.
In a new experiment published in Psychological Reports Lubomir Lamy and colleagues from the Universite de Bretagne-Sud examined the effect of love on the helping behaviours of men and women in a field experiment carried out on a busy shopping street in France.
Can you spare some change?
In Lamy et al.'s (2008) experiment, the researchers sent confederates, about half young men and half young women, to randomly approach people in the street. They asked each person if they would answer a few questions for one of two (fictional) journals:- 'Love and Feelings'. In this condition participants were asked to retrieve a 'love episode' and the associated emotions.
- 'Twenty-First Century'. In this condition participants were asked about a piece of music that meant a great deal to them.
After this participants were thanked and they continued down the street. Further along they were approached again, this time by someone asking them for change to buy a bus ticket. Although it seemed to people that these were unrelated incidents, this was, of course, all part of the same experiment.
Knight in shining armour
What the experimenters found was that when men were asked to recall a 'love episode' (love that expression!) they were much more likely to give money to a woman asking for money at the bus stop. A paltry 13% of men gave money in the 'music' condition, while this increased to 38% in the 'love' condition. Thinking about love seemed to make men more generous towards women.For women, meanwhile, thinking about love had little effect on their helping behaviour. They were more generous than men while thinking about music in the control condition (23% gave money) and only slightly more generous when thinking about love (27% gave money).
Lamy et al. (2008) explain this through the gender stereotypes adopted by men and women. The amount of help provided is affected by how men and women see their role in society. Men generally like to display chivalrous behaviour to women - rescuing the damsel in distress - and this becomes especially salient to men when they are encouraged to think romantic thoughts. It also doesn't hurt that they're in the street with a better opportunity to show off their chivalrous behaviour to others.
The effect on women, though, was not as marked. Although women are stereotypically nurturant and therefore keen to help others, especially friends or family, Lamy et al. (2008) suggest this doesn't stretch to strangers in a public place. This might explain why cueing women with a love episode didn't significantly increase the help they were willing to give to a stranger.
Help me!
This study is in line with previous research finding that women are more likely to be on the receiving end of help than men, and that when men help another person it is more likely to be a woman than a man. What it adds is the idea that men's gender roles can be made particularly salient to them with thoughts of love.Naturally women already understand this principle, whether consciously or not. That's why when they ask a man to do them a big favour, it is usually prefaced by: "How much do you love me?"
» Also see: People twice as likely to help than you think.
[Image credit: linhngan]
Memories Are Made of This
New memory study records the activation of human brain cells deep inside the living brain.
The mystery of what happens in our brains when we remember something is fascinating not only from a scientific perspective but also because the experience of recall can be so, well, memorable. Thinking backwards we become sensory time travellers; recalling sights, sounds, events, emotions - all in the blink of an eye. But what happens in our brains when we travel backwards?
For years scientists have told a story that goes roughly like this: when we experience something - say riding a bicycle for the first time - a network of neurons in the brain are activated. Then, later on, when we recall that first experience, that same network, or something like it, is activated again.
There is some round-a-bout evidence that this is exactly what is going on, but nothing direct. That is, until now. A US and Israeli research group have provided the strongest evidence so far that this story is accurate by recording individual neurons inside the living human brain.
Brain surgery for epilepsy
Recording the firing of individual human brain cells for experimental purposes is tricky as it's obviously highly unethical to cut people's heads open just so that scientists can satisfy their curiosity about how memory works. In this case though participants in a study carried out by Gelbard-Sagiv et al. (2008), reported in the prestigious journal Science, were undergoing brain surgery anyway and so agreed to an experiment.The volunteers all had epilepsy which had not responded to drug treatments. So, as a last resort they had consented to surgery, the first stage of which involves implanting electrodes into the brain in order to locate the exact source of the seizures. The probes were inserted into the medial temporal lobe, near the hippocampus, an area of the brain central to memory and how we remember events.
To treat their epilepsy effectively patients must then wait until they have a seizure so that neurosurgeons can locate the exact area of the brain that they need to treat. It was during this time that the experiment was carried out.
Experiencing, then recalling, The Simpsons
The experiment involved showing the thirteen patients short clips (5 to 10 seconds) of famous people, characters or animals who were engaged in some activity. For example some of the clips were from the comedy shows The Simpsons and Seinfeld. They then recorded the activity of any neurons that were in range of the probe.In total the researchers recorded the electrical signals of 857 individual neurons which they found specifically responded to one or other of these clips by increasing their firing rate, either singly or multiply. This is the memory trace being laid down in the brain.
Then participants were given a task to distract them after which they were asked to freely recall any of the clips they had seen earlier. Two very cool things happened. The first was that when participants recalled a particular video, say the clip from The Simpsons, exactly the same neuron (or neurons) increased its firing rate as had been activated when they watched the clip in the first place.
This is a nice finding but be careful about interpreting it - it doesn't mean that there's one neuron or a series of neurons that responds to The Simpsons. What it does mean is that, for whatever reason, this particular neuron was activated by this particular scene, almost certainly with a network of other neurons across the brain. But because researchers were only measuring a tiny proportion of the brain's neurons, they only saw the activation in one or sometimes a few neurons.
The second thing they noticed was that the neurons began to fire about 1.5 seconds before participants were conscious of remembering the particular clip. Effectively the researchers could predict which clip the patients were in the process of remembering before they actually said they became aware of it.
Resurrection of past neuronal activity
This study provides strong evidence that memory works through the reactivation of specific individual neurons in the hippocampus. Effectively things that happen to us activate networks of neurons in the brain, and when we recall past events at least some of these same neurons fire again.One of the authors of the study, Dr. Itzhak Fried, describes it like this: "In a way then, reliving past experience in our memory is the resurrection of neuronal activity from the past".
Calling memory a 'resurrection of neuronal activity from the past' might not sound like a terribly poetic description for one of our most profound experiences, but it's a phrase memory researchers will be very happy to hear because it suggests they're on the right track.
Memories Are Made Of This sung live by Dean Martin in 1956:
» Find out more about the 7 sins of memory.
[Image credit: Benedict Campbell]
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Hoodia is a spiny plant that grows in South Africa and Namibia which came to attention for its potential appetite suppressant properties. The active ingredient in Hoodia is thought to be a molecule dubbed 'P57', advocates of which claim it fools the brain into thinking it's not hungry.
Naturally the possibility of an effective diet pill has created much media interest, although there is currently little evidence of its effectiveness in humans in the scientific literature. For example one study on animals has suggested it might be effective, although there are questions about whether currently available supplements have enough of the active ingredient to have any effect.
Some studies have been carried out on humans suggesting hoodia might be effective, but these have not been published, were run in association with hoodia manufacturers and had small sample sizes.
Those wishing to purchase hoodia should be aware that reputable manufacturers send their product to an independent lab for testing to confirm how much of the active ingredient it contains. Companies such as Hoodoba do carry out this analysis and provide the results to customers.
» Visit Hoodia-Diet-Pills.com for hoodia news and hoodia diet pills information
Hoodia is a spiny plant that grows in South Africa and Namibia which came to attention for its potential appetite suppressant properties. The active ingredient in Hoodia is thought to be a molecule dubbed 'P57', advocates of which claim it fools the brain into thinking it's not hungry.
Naturally the possibility of an effective diet pill has created much media interest, although there is currently little evidence of its effectiveness in humans in the scientific literature. For example one study on animals has suggested it might be effective, although there are questions about whether currently available supplements have enough of the active ingredient to have any effect.
Some studies have been carried out on humans suggesting hoodia might be effective, but these have not been published, were run in association with hoodia manufacturers and had small sample sizes.
Those wishing to purchase hoodia should be aware that reputable manufacturers send their product to an independent lab for testing to confirm how much of the active ingredient it contains. Companies such as Hoodoba do carry out this analysis and provide the results to customers.
» Visit Hoodia-Diet-Pills.com for hoodia news and hoodia diet pills information