David Bradley – Page 358

Face Off

Our brains have a specific mechanism for recognising human faces that is separate from the mechanism that allows us to recognise objects like houses, cars, horses or even
parts of the body, according to Brad Duchaine of University College London. In a forthcoming paper in the journal Cognitive Neuropsychology, he shows how we recognise faces by analysing
one man, who cannot tell one face from another.

I assume he’s not generalising from this one case to the whole human race, but it’s an intriguing piece of work nevertheless.

Duchaine said: ‘There have been many theories about whether there is a part of the brain that deals specifically with faces or whether faces and other objects are handled by the same brain areas. We’ve found that there is a different, very separate, bit of the brain that lets you recognise faces. If those cells aren’t working, someone may not be able to tell two faces apart but they
will recognise two horses apart. This indicates that we go about looking at, analysing and recognising faces in a different way from how we recognise objects.

‘There are many theories out there about how we recognise faces and whether there is a separate social bit of the brain. So that we could draw firm conclusions to prove our facial recognition theory, we addressed all the alternatives in a single case study — Edward, a 53 year-old married man with a PhD in theology and physics, who happens to be unable to
recognise faces.’

For more than 35 years, researchers have debated whether face recognition is carried out by face-specific mechanisms or whether it involves more generic mechanisms that are also used for objects. Prosopagnosic patients (people who have difficulty recognising faces) have been some of the most powerful sources of evidence for there being face-specific mechanisms.

Scientists have put forward a number of different theories about why some people can’t recognise faces. One theory states that people with face recognition just have problems with objects that have a lot of curved surfaces (Curvature explanation); another theory states that it’s caused by problems with perceiving distances between parts such as judging the distance between eyes (Configural-processing explanation); another puts it down to a problem in recognising any individual item in a class — objects and faces (individuation explanation); another points to an inability to develop expertise with regularly encountered objects
(Expertise explanation).

But, for each case of prosopagnosia that has been scientifically tested there have always been several untested alternative explanations that could account for the inability to recognise faces. Each of these individuals has not been sufficiently tested to provide conclusive evidence for face-specific processes.

This study addresses all the existing theories that make a case against there being a specific mechanism in the brain that deals just with faces. Duchaine said: ‘We reject each in turn and eliminate all alternative accounts. The results show that face recognition uses mechanisms in the
brain that are different from those used in recognising anything else.’

The tests at UCL were done using a variety of types of objects — horses, guns, cars, greebles (novel objects). Edward performed just as well on as the test group people at differentiating between different objects but he just couldn’t tell faces apart.

Save her heart this Valentines

The European Society of Cardiology (ESC) is asking lovers across the Continent to send an e-card to their sweetheart to show support for women’s heart health this Valentine’s Day.

55% of women across Europe die of cardiovascular disease (CVD), it affects more women than cancer or any other ailment, yet most women are unaware that CVD poses such a big threat to their health nor realise that risk increases with age.

Visit the ESC website today and send an ecard to the woman in your life that shows you really care.

Simple changes in lifestyle – such as quitting smoking, exercising and eating more fruits and vegetables – can reduce the risk of heart disease. The ecards are in the Woman at Heart section of the website.

ADHD Black Box

According to a report from free email newsletter FierceBiotech, a federal advisory panel has told the US Food & Drug Adminstration (FDA) that it should apply its toughest warning label on drugs for attention deficit hyperactivity disorder (ADHD), such as Ritalin. According to Fierce, the recommendation comes as a surprise to the FDA, which usually follows its advisory panels’ advice but is not legally required to do so. At issue are reports that these drugs may have an increased link to heart disease risk.

You can subscribe for free to FierceBiotech for daily updates of bio and pharma news, by filling in a simple form on the Sciencebase site

The path less travelled

Ever wondered why your daily commute seems to feel longer and more boring as the days come and go? Yes? Well, so did a team of scientists at Manchester University, UK. Now, Andrew Compton and his colleagues think they have discovered the reason why.

Crompton’s team asked 140 architecture students from the University to estimate the distance between the student-union building to a familiar destination along a straight road. The research published in Nature today explains that they were effectively asked to guess the length of journeys they would have strolled (or staggered, says the press release!) many times.

First-year students estimated a mile-long path to be around 1.24 miles on average, whereas third year students stretched it to 1.45 miles. [That’s heavy precision, mind you and one can only hope that Manchester architecture students were not so nerdy as to actually give the distance with three significant figure accuracy, Ed.] Anyway, the results matched a theory that distances elongate in our minds because, over time, we begin to notice more and more details about the route.

To test this idea further, Crompton asked a second group of students to estimate 500 metres [they’ve switched from imperial to metric within two paragraphs!] in the cluttered tourist village of Portmeirion, Wales [home of 1960s cult TV show The Prisoner] and again on a road in Manchester city. The village distance seemed further.

The findings could help to explain why the walk to a destination sometimes feels shorter than the journey back. And, notes Crompton, it could help architects design cities that feel more spacious, simply by packing in more details for people to look at.

I’d also like to suggest that the work could make everyone’s daily commute seem much shorter by making us travel in boring smooth-walled tunnels, with very little to read and no interesting stimuli. What? They do that, already? Surely not!

EFF has Google over a Desktop

The Register reports today that the Electronic Frontier Foundation has issued a warning to potential users of Google Desktop (version 3) to configure it carefully.

The program’s “Search Across Computers” means some very private files, such as your web histories, documents, spreadsheets, presentations, PDF and text files in your “My Documents” folder could be held on Google’s servers for up to a month.

The idea is that you would login to your Google space and be able to search your own files from another PC. You can exclude filetypes and folders , but EFF has raised its proverbial eyebrows as the new version of Google Desktop could unleash a whole new set of security problems for non-technical users.

If you need more advice on computer security (and who doesn’t?), I can recommend The Hacker’s Nightmare, which I have mentioned several times in this blog.

Voodoo Insecticide

Regular visitor Rob Bowen emailed to tell me about the TechNeed site. Apparently, these guys want suggestions on how to create a chemical-free way to get rid of pests that won’t stain the carpet.

Well, efforts to find anything that is chemical free are doomed to failure from the off, unless you’re talking some energy form. Presumably, the chemophobics who write the site mean they want a physical method rather than something that relies on a compound acting as insecticide, which is fair enough.

But, Rob reckons the constraints they apply to their request for such a chemical-free pest remover are so tight that the only thing approach left is voodoo.

So, we’ll wait with interest to see if a commercially viable product emerges from this call to arms. I reckon they could cross-market it with those magnetic water softeners you wrap around your standpipe that are supposed to reduce limescale build up.

File under “pseudoscientific claptrap”

Coffee Experiment

I really am always too busy to drink my coffee as soon as it’s poured, and as a chemist I should know whether to add the cold milk or cream right away or when I come back to it, to make sure I have the hottest cup of coffee.

Anyway, I now know the answer. My wife somehow knew intuitively. But, if you want to confirm the idea that you should add milk or cream as soon as the coffee’s made, check out our science experiments section where we have just added details of a cool coffee experiment.

Simple instructions for finding out whether you should add cold milk or cream to your coffee right away if you’re not going to drink it immediately to make sure it’s as hot as it could be when you actually drink it.

Fill two plastic cups (styrofoam beakers), with the same quantity (150g) of water at the same temperature (use a lab thermometer* to check).

Next add 20g of cold water to one beaker.

Wait seven or eight minutes or so and add the remaining cold water to the other cup.

After ten minutes, you will not a 2-3 degrees Celsius difference between the two cups. The colder cup will be the one to which cold water was added last. If you want to know why, check out our topics in thermodynamics page for links to thermodynamics tutorials.

*Two Vernier sensors one in each cup would be ideal as it can record temperatures at regular intervals and display the charts on your PC.

For more science experiments, check out our science fair projects partner.

Open Access Referees

The new journal (Biology Direct), hopes to revolutionise the peer review process by placing the burden of selecting “referees” for a paer on the shoulders of the authors themselves and removing the protection of referee anonymity that has been the mainstay of the scientific publication system for decades, if not centuries.

The journal suggests that such an approach to peer review will increase “both the responsibility and the reward of the referees…eliminating sources of abuse in the refereeing process” and presumably reducing the risk of fraudulent results entering the scientific literature.

It remains to be seen whether referees will voluntarily expose themselves to the criticism of their peers for those papers they review, whether that’s authors wishing they’d picked someone else when a paper is slated, or rivals suggesting that a referee is at fault when a paper receives a positive review.

Taking the Bite Out of the Flu

According to a report on Alternet, homeopathy was more effective than a vaccine during the 1918 flu epidemic: (Flu). The one issue that isn’t addressed in the claim that, “Homeopathy may be more effective than flu shots” is that during the deadly flu outbreak of 1918, those patients who could have afforded to be treated with homeopathy would have been the idle rich who would like have retired to their country homes because of the Great War anyway and would not only have had a better diet, but a reduced risk of exposure.

Check out their coverage there are dozens of comments from posters pointing out dozens of other flaws in their argument.

For a relatively rational perspective on homeopathy, read my article – Homeopathy – all in the mind?

Constraint Satisfaction Problem

Wikipedia is fab, isn’t it? But, every now and then it throws up information that really doesn’t help. I’m currently writing a feature for the journal Complexus, for which I’m an editorial board member, and the phrase Constraint satisfaction problem is key to understanding the research paper I’m writing about. So, thinking good-old Wiki could help out with a neat and crisp definition for our readers, I plugged in the phrase, like you do. Bingo! There she blows!

Trouble is the definition apears to be entirely circular – a CSP being simply a problem the solution to which must satisfy certain constraints. That’s the equivalent of defining a long curvy yellow fruit as a “fruit that is yellow, curved, and long” isn’t it?

So, if anyone has a neat and crisp definition of CPS they’d like to share please let me know…

Now….where’s that banana?