People who don’t forget can still be tricked with false memories

“Time is the thief of memory,” wrote Stephen King in one of his many books. For some people, however, that is not true. They are gifted with what scientists call highly superior autobiographical memory (HSAM), which means they can remember in vivid detail every day of their life going back to childhood. But new research shows that even these special people are susceptible to forming false memories, sometimes more than normal people.

The first study of a person, later identified to be Jill Price, with this special ability was published as recently as 2006. Since then the database of HSAM individuals in the US has grown to about 30 people. It includes people like Bob Petrella, who can recall the date he met every one of his friends and acquaintances. Or Brad Williams, who can remember both what he did on any day and what significant world events occurred.

James McGaugh at the University of California Irvine was the author of the 2006 study, and for the past seven years he has been working to understand what makes HSAM individuals so special. A 2012 study showed, for instance, that HSAM individuals have different brain structures. They posses more white matter in areas linked to autobiographical memory. But because there are so few of them, “We still don’t know enough to be able to draw robust conclusions,” says Martin Conway, a cognitive psychologist at City University London.

Knowing how HSAM people form memories would be a great leap in our understanding. With graduate student Lawrence Patihis, McGaugh set out to fill that gap. One way to do that would be to test if HSAM individuals are susceptible to false memories. After all, memories are easy to distort. It happens to every one: the young, the old, the intelligent and the dumb. Now, in a study just published in the Proceedings of the National Academy of Sciences, Patihis finds that HSAM individuals too can be tricked to possess false memories.

Not so perfect

For the study, Patihis recruited 20 out of the 30 known HSAM individuals in the US. They were matched, by sex and age, with 38 people with normal memory. All of the participants were then given three tests.

In the first test, each participant was shown a series of words that were all supposed to be connected to a “lure word”. So if the lure word was “lamp” then they will be shown words like light, table, shade and stand, but not the word lamp. After they have seen the list, they are asked if they saw the word lamp. People with normal memories got the answer wrong seven out of ten times. HSAM individuals too got it wrong just as much.

The second test was more elaborate. It showed a slideshow of photos depicting a crime. After 40 minutes, they were then shown words describing the crime with misinformation sprinkled in them. Then 20 minutes later they were tested to see how many people believed the misinformation to be true. This time HSAM individuals did worse than normal people. They were 73% more prone to false memories. “Maybe HSAM individuals form richer memories through absorption of more information and that is why they are also more susceptible to false ones too,” says Patihis.

Perhaps it is easy to manipulate recent memories. So in the third test Patihis looked to test long-term memory. All participants were asked to recall the September 11 terrorist attacks. They were then given irrelevant facts about that event, one of which was not true (someone captured the footage of United 93 in Pennsylvania). After 15 minutes, all participants were then asked whether they had see such a footage. Like the first test, normal people and HSAM individuals performed almost equally badly on this test.

“This shows that maybe people with superior memories form them just like normal people. Thus, in the process, they are also prone to making the same mistakes,” says Patihis. Equally, they may use a different process of forming superior memories, but one that has same problems as that of the normal process.

There is still contention among experts whether HSAM individuals are “special”. K. Anders Ericsson of Florida State University says, “Our work has pretty much concluded that differences in memory don’t seem to be the result of innate differences, but more the kinds of skills that are developed.” To which McGaugh says, “You’d have to assume that every day they rehearse it… The probability of these explanations dwindles as you look at the evidence.”

Price had admitted that remembering everything meant bad memories were always around to trouble her. It led researchers to believe that such superior memory may come at a cognitive cost of lost abilities, or less happier lives. But research since has shown that not to be the case. HSAM individuals tend to have similar lives to normal people. With the latest study, McGaugh has shown one more task where HSAM individuals are normal. They too may be made to believe that as a kid they were lost in a shopping mall, even if that isn’t true.The Conversation

First published in The Conversation.

Image credit: alinassiri

The art and science of remembering things

Review of Joshua Foer’s Moonwalking with Einstein, as part of my #100bookschallenge.

Moonwalking with Einstein is the story of a journalist who went to cover the 2005 US Memory Championship as an assignment for an article, and then went on to win the 2006 event. He got so obsessed with the people and their achievements that he decided to try it out himself. In that one year he with trained by men which by normal standards would be called freaks of nature. They could memorise the order of a deck of cards in under 30 seconds or 800 random digits in 15 minutes (full list of records).

Foer interspaces his year with the history and science of memorising. He walks the reader through the time when poets committed to memory the works of other poets so that it could be passed down the generations. There is a record Socrates’s outrage on the use of writing and the amount of stress that was given on memory training during the time before the printing press. But Gutenberg’s invention was the final nail in the coffin for those memorisers, because common people could then start to rely on books as an external form of memory.

memory palaceSince Gutenberg there were some attempts at renewing this lost art, but it wasn’t until the likes of Tony Buzan in the late 20th century that it finally happened. Buzan built an industry around the tools and methods of increasing one’s memory, and even founded the World Memory Championship. He sold improving memory as being akin to increasing intelligence.

And although IQ scores do not depend on the use of one’s memory, there is still a good case to be made for putting in the effort to expand it. After all, new ideas are only mashed up versions of old ones. However much easy it has become to store our memories in external devices, without internalising them once again they are useless.

There is now a large community of people who use these age-old techniques (and comes up with new ones) like that of filling memory castles with outrageous images to help them commit to memory things like lists, random numbers, binary digit sequences, decks of cards, poems etc.

This is what Foer trained himself to be able to achieve, and eventually won the US competition for it. What Foer convincingly demonstrates through the book, based on scientific research and his own experience, is that expanding one’s memory is only a matter of deliberate practice.

What Foer achieved is no mean feat. But, at the end, despite being a great story, Foer’s increased memory does him little good in his daily life where paper, computers and cell phones can often handle the task better. Sure he can memorise many phone numbers, lists and even complete poems with relative ease, but he still carries with him his dictaphone and notebook. And although he doesn’t say this explicitly, it seems his memory expansion was only for things that are well-defined, clearly laid and can be written down in lists.

Image from here.

Best way to remember names

Associate names with a powerful visual image. Reagan with ray guns. Lincoln with chain links. Manmohan with a smiling brain. It can be more powerful if you place this image in your mind at the place you came to know about their name.

Now read on to know why this technique works. Here is the Baker-baker paradox which helped develop the best way of remembering names:

A researcher shows two people the same photograph of a face and tells one of them that the guy is a baker and the other that his last name is Baker. A couple days later, the researcher shows the same two guys the same photograph and asks for the accompanying word. The person who was told the man’s profession is much more likely to remember it than the person who was given his surname.

This happens because:

When you hear that the man in the photo is a baker, that fact gets embedded in a whole network of ideas about what it means to be a baker: He cooks bread, he wears a big white hat, he smells good when he comes home from work. The name Baker, on the other hand, is tethered only to a memory of the person’s face. That link is tenuous, and should it dissolve, the name will float off irretrievably into the netherworld of lost memories. 

From Joshua Foer’s Moonwalking with Einstein

How a Homeopath tried to understand the science behind Homeopathy

At Café Scientifique, last night, I heard Dr. Stephen Cartwright speak on ‘Homeopathy – Dispelling myths and establishing facts’. I had never been to one of these CafeSci evenings, but going from the description, I was hoping there will be many who will be interested in hard scientific facts and theories. Even then, I took a print of the Sense about Homeopathy poster published by Sense about Science, just in case anyone might be interested in knowing more about it later. But within the first few minutes of the talk, I knew I would not need it.

Dr. Stephen Cartwright, is a molecular biologist who, with support from private donations, started researching homeopathy in 2009. Prior to that he trained and setup his own business as a homeopath in Oxford in 1988. Last night, he began his talk with a story about how he first got into homeopathy, and that is when I neatly folded my Sense about Homeopathy poster and put it in my bag.

In 1984, he visited a homeopath, out of curiosity. After talking to the homeopath, he was prescribed some pills which he happily took; only to develop symptoms of sinus within 24 hours. That intrigued him and he took up the study of homeopathy.

‘After 20 years of practising homeopathy, I really wanted to understand the chemistry behind these remedies and that’s why I have put a lot of thought and came up with some experiments to gain some insight. He continued, ‘I will have to delve into some chemistry, please forgive the jargon.’ He goes onto explain his experiments. ‘It is well known’, he says, ‘that homeopathic potencies are affected by sunlight and magnets’ and thus of all the analytical techniques that man has invented to understand the chemistry of atoms he could only use was visible light spectroscopy.

Some definitions before we proceed; succussion means vigorous shaking of a diluted homeopathic preparation in order to activate the medicinal substance; potency is the dilution factor and in homeopathy, a solution that is more dilute has a higher potency.

Panacea? (Image: The Guardian)

Process: In a special cuvette, he mixes a drop of his potencies with 90% ethanol and measures absorption against a control. Control that he uses is non-succussed water, because homeopaths accept that water that has not been methodically shaken does not have any homeopathic remedy in it. The potencies which could be of various dilutions contain a poly substituted phenol. ‘More details cannot be divulged as it is a patentable finding’, he says.

Observations: With an increase in potency (increase in dilution) he sees increase in the absorbance. Different remedies give different absolute absorbance but same trend. The trend is not linear and because he hasn’t done enough experiments he is unable to calculate the trend. Also, a similar trend is observed with an increase in the succussion of a particular potency used. ‘Quite strange’, he admits.

Additional experiments: ‘Why’, he thought, ‘is it that all homeopathic remedies are made in ethanol?’ He did the same tests with 30 different alcohols instead of the potency and found that the trend was found to be exactly same in case 2,4-pentane diol. What does that mean? Now he goes a step further on his claims and makes another theory to explain this phenomenon, ‘2,4 pentane diol is like two ethanol molecules back to back, thus the potencies might be in some way ordering the ethanol molecules to arrange themselves to form something like 2,4-pentane diol.’

Wow! A Nobel Prize deserving discovery, why hasn’t he published it? Oh wait, there is a problem.

Problem: Results are not reproducible because too many factors affect his experiments, factors like time of the day, place in the lab, how many times was the potency shaken, etc. He also observed that when very rarely he has managed to have all the factors in control, he found that on somedays he got the result and on somedays he did not. So how to explain another strange pheonomenon? Of course, another theory. He hypothesises that there is an oscillation in the potency. On somedays it shows effects and on somedays it does not.

On clinical trials he says, ‘These oscillations are the reason why clinical trials fail. Homeopathic remedies behave in strange ways and these clinical trials don’t take that into consideration. Obviously, the results will never be as predicted.’

On expiry date he says, ‘Homeopathic remedies have no expiry date. On occasions, I have found 20 year old medicines are as active as one’s made today.’

Alternative medicine (Image: Chicagoland Homeopathy)

On future scope he says, ‘Homeopathy has been here for over 200 years. 40% of all prescriptions in India are homeopathic prescriptions. There is huge market for homeopathy but because it behaves in these strange ways we need new assays to test these remedies. The demand for these assays is urgent and the inventor will make a lot of money.’

At the end he quotes Sir Arthur Conan Doyle, who he claims based the character of Sherlock Holmes on a homeopath, “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”

Enough of the talk, let’s move on to question answers. I’ll enlist the ones I remember.

Q: When you went to the homeopath in 1984, what problem did you have?

A: Nothing, I was quite healthy. Huh? Then why were you prescribed pills? Oh that! You see in talking to him for over an hour, I realised there were so many things that were wrong with me.

Q: What are your thoughts about the claim that water has memory?

A: Perhaps, I don’t know, there has to be some way to explain this strange phenomenon. May be it is true.

Q: Were the oscillations random or regular like a sinusoidal wave?

A: As far as I know, they were regular. Doesn’t that mean that you can then time clinical trials on the days you know the remedy will have a cure!!

Q: Considering that the potency is shaken in 90% ethanol and your claim that with more shaking you observe more absorbance. Is it possible that ethanol is simply dissolving glass or some impurities that are present in glass?

A: I am not aware of it. We take care that the glass used is clean. Of course you do. Did we doubt that? We were talking about dissolving glass or the impurities that get embedded in glass during the manufacturing process.

Q: If homeopathy is so widely used, why hasn’t homeopathy come up with new potencies?

A: Of course we have, you will be able to find potencies of tetracyclines. But te

tracyclines are compounds made to combat disease. Making potencies that way is against the homeopathic principles, right? Homeopaths make potencies of things that cause the disease, right? Oh yes, we make potencies of tetracyclines to combat the side-effects produce by this drug.

Q: This room has many chemists today, including myself and we would to know if you would be willing to share your spectral data with us to let us analyse them?

A: Yes, I’d be willing to that. I am happy to collaborate. Surely, it will be better if you do this before you face the peer-review process.

Q: You have said that you have not published any of this research. But clearly these results have use for homeopaths, have you shared the information with them yet?

A: Not yet. I believe in coming up with a working hypothesis before I do that.

Q: Have you presented your results at a conference?

A: No I do not have money to do that. It is very difficult to find funding because of the fickle nature of the results I’ve obtained. But I will some day. That’s why I give talks at places like these. I came here hoping to be asked intelligent questions, of which there were none, so that I am able to hone my skills of defending my case of homeopathy.

It surprised me that in the many questions asked, no one ever brought the placebo effect into the conversation. It may be because even without that weapon he wasn’t able to come up with convincing answers for the audience. The last question he was asked is the best conclusion I could have asked for to conclude my blog post.

Q for the audience: Will people who have changed their minds about homeopathy after today’s talk, for the better or worse, please raise their hands?

3 out of about 30 raise their hands. The old man who asked this question says, ‘There, Dr. Cartwright, that was a predictable and I dare say, reproducible result.’