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Posts Tagged ‘memory’

Eye Movements and Lie Detection – Another Myth?

19/07/2012 1 comment

This is not a proper post. It is more like a long tweet. Having done a similar study last year and finding no significant results I felt I had to share this with you.

You have probably heard that right-handed people look up to their right when they are telling a lie, while they look up to their left when they are telling the truth. Surprisingly, even though many people believe this is to be scientifically established, a quick google search comes up with no relevant peer-reviewed papers. Richard Wiseman and colleagues investigated this notion with three different studies. All three studies provided no evidence to support the notion. So it seems that the patterns of eye-movements do not aid lie detection.

Why did this myth survive for such a long time? Probably thanks to psychologists’ reluctance to publish negative results…

Here is the abstract:

Proponents of Neuro-Linguistic Programming (NLP) claim that certain eye-movements are reliable indicators of lying. According to this notion, a person looking up to their right suggests a lie whereas looking up to their left is indicative of truth telling. Despite widespread belief in this claim, no previous research has examined its validity. In Study 1 the eye movements of participants who were lying or telling the truth were coded, but did not match the NLP patterning. In Study 2 one group of participants were told about the NLP eye-movement hypothesis whilst a second control group were not. Both groups then undertook a lie detection test. No significant differences emerged between the two groups. Study 3 involved coding the eye movements of both liars and truth tellers taking part in high profile press conferences. Once again, no significant differences were discovered. Taken together the results of the three studies fail to support the claims of NLP. The theoretical and practical implications of these findings are discussed.

The rest of the article can be found on PLoS ONE.

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Future Imagining And Episodic Memory

27/08/2010 2 comments

Neuroimaging and lesion studies suggest that imagining the future (i.e. envision future personal experiences) is strongly connected with retrospective memory (i.e. remembering past experiences). Two recent papers published on Neuropsychologia investigated the relationship of retrospective memory and future imagining, as well as their common neural correlates.

Kwan, Carson, Addis, and Rosenbaum (2010) report the case of H.C., a young woman with developmental amnesia associated with bilateral hippocampal loss. Episodic memory seems to depend on hippocampal function (Yancey & Phelps, 2001; Maguire, 2001). Compared to matched controls H.C. was found to be impaired both in tasks requiring past and future event generation. Her performance was similarly deficient in both tasks. According to Kwan and colleagues:

These results indicate that mental time travel can be compromised in hippocampal amnesia, whether acquired in early or later life, possibly as a result of a deficit in reassembling and binding together details of stored information from earlier episodes

Maguire, Vargha-Khadem, and Hassabis (2010) report the cases of two patients (P01 and Jon) with dense amnesia and 50% volume loss in both hippocampi. P01 suffered from adult-acquired amnesia, but unlike previously reported cases was found to be unimpaired at future imagining tasks. The authors suggested that P01 could have been an atypical case, and in order to investigate this they identified another patient with similar neuropsychological profile, Jon. In spite of his dense amnesia, Jon was able to imagine future experiences in a comparable manner to control participants. According to one of the possible explanations proposed by Maguire and colleagues:

Activity in their residual hippocampal tissue supports the ability to imagine new scenarios, and that this is the key feature. Residual hippocampal tissue was active in both patients and in similar circumstances to control participants. Whilst we cannot definitely relate function to these hippocampal activations, we suggest the activations might indicate some preserved hippocampal function which is also sufficient to support their preserved ability to imagine scenarios

ResearchBlogging.orgKwan, D., Carson, N., Addis, D., & Rosenbaum, R. (2010). Deficits in past remembering extend to future imagining in a case of developmental amnesia Neuropsychologia, 48 (11), 3179-3186 DOI: 10.1016/j.neuropsychologia.2010.06.011

Maguire, E., Vargha-Khadem, F., & Hassabis, D. (2010). Imagining fictitious and future experiences: Evidence from developmental amnesia Neuropsychologia, 48 (11), 3187-3192 DOI: 10.1016/j.neuropsychologia.2010.06.037

The riddle of experience vs. memory: Daniel Kahneman Talk (TED)

Using examples from vacations to colonoscopies, Nobel laureate and founder of behavioral economics Daniel Kahneman reveals how our “experiencing selves” and our “remembering selves” perceive happiness differently. This new insight has profound implications for economics, public policy — and our own self-awareness. (Recorded at TED2010, February 2010 in Long Beach, CA. Duration: 20:07) from TED

A Few Calls a Day Keep Alzheimer’s Away?

07/01/2010 3 comments

Do you remember all those reports trying to find a connection between cellphones and unpleasant things, like cancer, ear aches, etc? Worry not!? Now thanks to researchers from the University of South Florida you can embrace your newly purchased Nexus One without worrying about possible side-effects.

After long-term exposure to electromagnetic waves such as those used in cell phones, mice genetically altered to develop <a href=”“>Alzheimer’s performed as well on memory and thinking skill tests as healthy mice, the researchers wrote in the Journal of Alzheimer’s Disease.

The results were a major surprise and open the possibility of developing a noninvasive, drug-free treatment for Alzheimer’s, said lead author Gary Arendash of the University of South Florida.

He said he had expected cell phone exposure to increase the effects of dementia.

“Quite to the contrary, those mice were protected if the cell phone exposure was stared in early adulthood. Or if the cellphone exposure was started after they were already memory- impaired, it reversed that impairment,” Arendash said in a telephone interview.

Arendash’s team exposed the mice to electromagnetic waves equivalent to those emitted by a cellphone pressed against a human head for two hours daily over seven to nine months.

At the end of that time, they found cellphone exposure erased a build-up of beta amyloid, a protein that serves as a hallmark of Alzheimer’s disease.

The Alzheimer’s mice showed improvement and had reversal of their brain pathology, he said.

“It (the electromagnetic wave) prevents the aggregation of that bad protein of the brain,” Arendash said. “The findings are intriguing to us because they open up a whole new field in neuroscience, we believe, which is the long-term effects of electromagnetic fields on memory.”

Arendash said his team was modifying the experiment to see if they could produce faster results and begin testing humans.

Despite decades of research, there are few effective treatments and no cure for Alzheimer’s, the most common form of dementia. Many treatments that have shown promise in mice have had little effect on humans.

More than 35 million people globally will suffer from Alzheimer’s disease or other forms of dementia in 2010, according to the Alzheimer’s Association.

There has been recent controversy about whether electromagnetic waves from cellphones cause brain cancer.

Co-author Chuanhai Cao said the mice study is more evidence that long-term cellphone use is not harmful to the brain.

Groups such as the World Health Organization, the American Cancer Society, and the National Institutes of Health, have all concluded that scientific evidence to date does not support any adverse health effects associated with the use of cellphones.

(Editing by Alan Elsner)

I wouldn’t recommend spending too many hours on the phone, though, as the long-term effects are not known yet. I’m really curious to see if other studies will replicate these results in humans. Imagine how fierce the competition between Google and Apple will be then!

Goodbye Rain Man

25/12/2009 2 comments

Kim Peek , the man who inspired Dustin Hoffman’s well known character in the film Rain Man , died a few days (19/12) ago of heart attack at the age of 58.
Peek was not able to live on his own and depended on his father for most everyday activities. However, he was known for his extraordinary memory, mathematical and reading skills. Even though, Peek was though to be autistic, scans performed in 2008 revealed that the most likely diagnosis was FG syndrome .

Here are a few links about the famous savant:

videos of Kim Peek .
Scientific American’s article: Inside the Mind of a Savant
Kim Peek – The Real Rain Man (Wisconsin Medical Society entry)
Kim Peek has left the buliding (Mind Hacks)

Project H.M. & Clive Wearing’s Diaries

26/11/2009 2 comments

Project H.M.

H.M. is considered to be one of the most famous cases in neuropsychology. His dense amnesia contributed significantly to our understanding of human memory. On December 2nd, exactly a year after his death, anyone interested will have the chance to watch the dissection of his brain. I’m really looking forward to this (that sounds a bit weird).

According to the Project H.M. official blog:

“On December 2nd, 2009 we will begin slicing the brain of the amnesic patient H.M. into giant histological sections. The brain specimen is going to be frozen and sectioned whole during one continuous session that we expect will last approximately 30 hours”

If you’re interested in finding more about the project and the next phase, visit the Project H.M. website

Clive Wearin’s Diaries @ Wellcome Trust Exhibition

A few months ago I wrote a post on Clive Wearing, another case of amnesia. If you’re lucky enough to live in London, you’d be interested to know that the Wellcome Trust’s new collection, titled “Identity: Eight Rooms, Nine Lives” hosts Wearing’s famous diaries in the Samuel Pepy’s room. The exhibition will be on from today until April and it’s a part of The Identity Project (Pressure Drop could also be interesting). Oh, and it’s free.  For more information visit the exhibition’s website. They have a special section on Clive Wearing including a number of interesting videos.

 

image: Salvador Dali’s – the disintegration of the persistence of memory

 

How Does Your Memory Work?

While I was searching for Prof E. Warrington’s publications, I came across this interesting documentary on memory, which was originally broadcast by BBC2.

You can find a short description and the video below:

You might think that your memory is there to help you remember facts, such as birthdays or shopping lists. If so, you would be very wrong. The ability to travel back in time in your mind is, perhaps, your most remarkable ability, and develops over your lifespan. Horizon takes viewers on an extraordinary journey into the human memory. From the woman who is having her most traumatic memories wiped by a pill, to the man with no memory, this film reveals how these remarkable human stories are transforming our understanding of this unique human ability. The findings reveal the startling truth that everyone is little more than their own memory.

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