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Wednesday, September 30, 2009

MAOis For Dummies (And British Pundits)

Allegedly, British Prime Minister Gordon Brown takes a monoamine oxidase inhibitor (MAOi) antidepressant.

That's the rumor, based on the rumored fact that he is unable to eat certain things, notably cheese and Chianti wine. These are foods rich in tyramine, a chemical that's normally harmless, but can be toxic in people taking MAOis. So, if Brown is indeed on a Chianti-and-cheeseless regime, he almost certainly is taking one of the several MAOis on the market today.

The original source for this idea is this blogger, who claims to have heard it from an unnamed Brown aide. Is he to be believed? A glance over his website shows he is hardly an impartial commentator, and he goes on to demonstrate his psychological insight with statements like
"Obsessive Compulsive Disorder (OCD) is relatively common. Most of us display some obsessive features in everyday life, but under stress a minority of people become borderline or actual OCD in their behaviour, and need medication to control both this and the depression which almost always presents soon afterwards. ... Gordon Brown's symptoms are obvious when viewed in this light: the constant repetition of phrases, and an almost embarrassing (for his Party) need to spray every Parliamentary answer with statistics... they - and the constant speech repetition - represent Brown's unconscious means of controlling the severe anxiety that accompanies depression with OCD."
So one might think that his credibility is somewhat questionable. This hasn't stopped certain corners of the British blogosphere from getting very excited, however, and even respected political journalist Andrew Marr yesterday quizzed Brown about the issue.

Unfortunately, while many are eager to write about Brown and his possible pills, few of them seem to know anything about psychiatry or antidepressants, which has led to some embarrassing errors. So, for the benefit of British pundits, here are some helpful facts.

MAOis -
  • are not "powerful", "heavy duty" antidepressants. In terms of effectiveness, they are no better, on average, than Prozac. In fact, no antidepressant is much better than any other one. They differ in terms of side effects, but not "strength". For what it's worth, current opinion is that if there is a best antidepressant, it is escitalopram, a modern Prozac-like SSRI with very mild side effects, which is just about as unlike a MAOi as you can imagine.
  • do not "impair" or "affect judgment". Antidepressants don't. Except that they treat depression, and someone who's happy might make different judgments to someone who's depressed. But these drugs do not affect judgment in the way that intoxicants like alcohol or cocaine do. You don't get high on them. This is why they have no street value. Most drugs which impair judgment get used recreationally, because having your judgment impaired can be fun. Antidepressants aren't.
  • are not exclusively used in "severe depression". They are usually reserved for when a patient has not responded to other drugs. This is because of their troublesome side effects, including high blood pressure, and the fact that you can't eat cheese. But "treatment-resistant" depression is not the same as "severe" depression. In fact, the more severe the depression, the more likely it is to respond to treatment with conventional drugs. If Brown is on MAOis, he has probably tried at least two or three other drugs, but this is by no means uncommon because antidepressants just don't work especially well. According to the largest trial in a real-world setting, the STAR*D project, only 30% of people fully recover on their first antidepressant and only 30% of the rest respond to the second one.
  • are not especially effective in OCD, as the source of the rumor claimed - "this older class of drugs has one huge advantage: for severe depression and obsessive compulsive disorder it remains very effective", emphasis in the original. This is just flat-out wrong. Other antidepressants are more useful in OCD. Here's a recent review of drug therapy for OCD. MAOis get a mention... right at the end, after (deep breath) SSRIs, clomipramine, atypical antipsychotics, SNRIs, pregabalin, tricyclic antidepressants, and benzodiazepines. Here's the only published trial comparing a monoamine oxidase inhibitor to another drug, Prozac, for OCD. The MAOi didn't work, Prozac did.
  • were the first class of antidepressants to be discovered; the very first, iproniazid, was discovered in 1952. Others followed, such as tranylcypromine, phenelzine, and selegiline. Today, there are a handful of MAOis on the market. These include some newer drugs such as moclobemide (which has milder side effects) and the selegiline transdermal patch (which carries fewer dietary restrictions). MAOis are primarily used to treat depression, but are also used in Parkinson's disease.
So, even if Brown is taking MAOis, this has no implications regarding his mental state or competence to govern. What about the possibility that he is depressed? This could be relevant, but considering that the most popular British leader of all time famously suffered from severe depressive episodes throughout his life, including his time in office, the historical precedents are not unfavourable.

Realistically, none of this is going to change people's minds. No-one is really concerned about the possibility that Gordon Brown is using MAOis, or even the possibility that he's depressed. Rather, a lot of people just really don't like him, and this rumor is the latest stick with which to beat him. Blogger Guido Fawkes has been asking "Is Brown Bonkers?" for months. As one journalist put it, "Whether literally the case or not, however, this rumor carries the kind of psychological truth that tends to be more damaging than fact." Which didn't stop him from repeating the rumor uncritically.

[BPSDB]

Tuesday, September 29, 2009

Traditional Ice Lollies - WW



Colourful homemade ice lollies


I was so excited to see these colourful ice lollies at a Family Day Fun and Food Fair.

When I was a kid, this traditional ice lolly was a rare treat for me. It used to cost 10 cents for one but today, it is selling at S$1! Gosh.


S$1 for an ice lolly

I was living in a subsidised flat with my family then. One enterprising neighbour had a fridge and she would make ice lollies to sell to the children in the neighbourhood. Her business was so good that she had to make 3 batches daily.

There were different flavours every day. I prefer red bean or sour sop or sour plum lollies. These days, the factory-produced ice lollies have a wider selection of flavours, but some tastes like coloured syrup. :P .

cold snack on a hot day!

I was very happy to have an ice lolly to snack on in those days but nowadays, if I offer to give kids a cold snack, they would prefer ice-cream. And they are not shy to ask for expensive, branded ones. One scoop of ice-cream for S$3.50! aiyoooh ..... I can buy a plate of chicken rice!   







First Commenter - Karen

Monday, September 28, 2009

Encephalon #76

Welcome to #76 in the fortnightly Encephalon blog carnival series.
That's it for this time. We're still looking for a host for the next edition, so if you're a neuro/psychology blogger and you'd like to be the next Encephalon editor, please email encephalon dot host at gmail dot com.

Saturday, September 26, 2009

Panic! In the fMRI Scanner

Continuing the theme of interesting single case reports, I was pleased to see a paper about brain activity in someone who suffered a panic attack in the middle of an fMRI brain scan experiment.

The unfortunate volunteer, a 46 year old woman, was taking part in an experiment looking at restless-leg syndrome. The scan lasted 40 minutes, and everything was going smoothly until quite near the end, when out of the blue, she had a panic attack.

Obviously, the scan had to be abandoned - as soon as the volunteer pressed the emergency "panic button", they stopped the scan and got her out of the MRI. (This kind of thing is why we have such buttons!) However, they decided to see what happened in the woman's brain as the panic started using the data they acquired up to that point.

Here's what they found: the top graph here shows her heart rate. It starts increasing a bit and then spikes, which shows exactly when the attack occurred. What about the brain? Well, amygdala and left insula activity sort of increase around this time. A bit. If you stare at the lines hard enough.

If you believe they did, it makes sense because the amygdala is known to be involved in anxiety (amongst other things) while the insula is responsible for the perception of the body's internal state, which is rather out of whack during a panic attack.

What doesn't make sense is the middle temporal gyrus bit, which was statistically the only part of the brain where activity was significantly correlated with heart rate (in whole-brain analysis). That region is not believed to have anything to do with panic, and to be honest, it's probably just a fluke.

This is only the second published report about panic during fMRI. There was one previous paper from 2006 about an attack in someone with a history of panic, which also found amygdala activation. But there are sure to be others out there which haven't made it into print - anxiety and panic during scans is not unheard of (the scanner is rather claustrophobic). It would be interesting to get more data on this, because it's obviously rather hard to research real-life panic attacks, on account of them being unpredictable.

ResearchBlogging.orgSpiegelhalder, K., Hornyak, M., Kyle, S., Paul, D., Blechert, J., Seifritz, E., Hennig, J., Tebartz van Elst, L., Riemann, D., & Feige, B. (2009). Cerebral correlates of heart rate variations during a spontaneous panic attack in the fMRI scanner Neurocase, 1-8 DOI: 10.1080/13554790903066909

Twisted ECL - PhotoHunt

PhotoHunt theme : Twisted


All twisted!

At last night's Singapore F1 Night Race, while the guys fixed their eyes on the F1 races, we bored ladies have to amuse ourselves telling twisted stories :

I was given this topic :

Sex is not the answer. Sex is the question. "Yes" is the answer.

 ~~~~@~~~~

ECL's twisted answer :

Hubby : Sex?
ECL : Yes!!!

Before a medical checkup, I have to fill in a questionaire.
The good-looking, young male doctor asked me without lifting his head, "Sex?"
ECL (can't believe her good luck!)  : Yes!!!

aiyahhh...... twisted minds!  This young doctor is not sex starved, blind nor bold. He was asking if I'm still having an active sex life. :P











First Commenter -Marzie

Thursday, September 24, 2009

Spot The Difference

As part of my extensive research into the famous dead fish brain scanning study, I decided to read a little bit about the Atlantic salmon (Salmo salar), the fish which started it all.

It turns out, at least according to Wikipedia, that there are various interesting things about this species, for example, it's "much more aggressive than other salmon". Who knew?

However, by far the most interesting thing is that developing salmon embryos are about the cutest things in the world, and look exactly like smiley faces, or maybe Pacman. Those dark spots really are the eyes.

Endless forms most beautiful, indeed.

Tuesday, September 22, 2009

Melbourne

I'll be headed off to Melbourne during the term break to visit some friends and see the sights! It was a toss-up between flying, driving, or grabbing a bus, and as always, the cheapest option has prevailed. Firefly Express has pretty low rates and we don't really mind sitting in a bus for a few hours anyway...! We'll at least get tons of reading done, and not have to worry about whether we're

The Man With Half A Brain

A lovely new paper reports in fascinating detail on a man who lost a uniquely large portion of his brain: Bilateral limbic system destruction in man.

The authors, Feinstein et al from Iowa City, have studied the patient, "Roger", for 14 years. Roger was born in 1952, and lived a fairly uneventful life until he contracted herpes simplex encephalitis (HSE) at the age of 28.

HSE is an extremely rare condition in which the herpes virus infects the central nervous system. Untreated, it is fatal in 70% of people. Survivors suffer varying degrees of neurological damage. Roger suffered more than most - his is the worst case of herpes encephalitis damage among patients currently alive, and there are only three recorded cases of similarly extensive lesions. Roger lost almost his entire "limbic system":
The amount of destroyed neural tissue is extensive and includes bilateral damage to core limbic and paralimbic regions, including the hippocampus, amygdala, parahippocampal gyrus, temporal poles, orbitofrontal cortex, basal forebrain, anterior cingulate cortex, and insular cortex. The right hemisphere is more extensively affected than the left, although the lesions are largely bilateral.
"Limbic system" is an old, vague, but still popular term for a collection of brain structures located deep in the centre of the brain (but not to be confused with the basal ganglia). It's often thought of as the "primitive", "emotional" part of the brain, and there is some truth to this. Roger's limbic system was profoundly damaged on both sides; on the right side, the lesion included the whole temporal lobe and most of the ventral prefrontal cortex as well.

What happened to Roger's mind when his brain suffered such injury? In many ways, remarkably little. His only major impairment is profound anterograde amnesia: he is unable to remember anything that has happened since the infection, which was 28 years ago.
For Roger, not much has changed over the past 28 years. He has virtually no episodic memories for any events that have transpired over the past three decades. For example, he has no recollection of 9/11, and when shown pictures of the planes crashing into the World Trade Center he often responds with bewilderment, speculating that Russia must be attacking America.
This is, obviously, a disabling deficit: Roger cannot lead a normal life. But in other areas of mental functioning, he is quite normal. His IQ is above average; his speech and language abilities are excellent; his vision and hearing are normal, although he has no sense of taste or smell. His short term (working) memory, attention, and reasoning abilities are unimpaired. His motor abilities are fine - he is reportedly an excellent bowler - and he is able to improve motor skills through practice. And his recall of things which happened before the infection is largely preserved, although the few years just before the infection are partially lost.

Fascinatingly, Roger's personality and emotional life seems to have been changed by the infection as well, but in a rather fortunate way -
Roger appears remarkably unconcerned by his condition. He hardly ever complains and, in general, shows little worry for anything in life. Both of his parents and his sister fervently claim that “Roger is always happy,” an observation that is consistent with our own impression. Moreover, based on his family’s report, Roger is paradoxically happier now than he was before his brain damage. ... His premorbid disposition of being somewhat reserved and introverted has shifted to being outgoing and extroverted...

Most conversations with Roger involve animated speech that is replete with prosody, gesture, and, often times, laughing. He readily displays signs of positive emotion including happiness, amusement, interest, and excitement. As previously noted, Roger’s positive mood has remained essentially unchanged over nearly three decades.
His only other reported quirks are an insatiable appetite, and a habit of collecting and holding onto everyday items.

What does all this mean? Neuroscientists will find little about the case surprising. No textbooks are going to have to be rewritten. Roger's inability to form new memories, combined with preserved memory of events up to the few years before the damage, is similar to that seen in other cases of bilateral hippocampus damage. The most famous being the sadly recently deceased patient "H. M.", but there have been plenty of others. The hippocampus seems to be necessarily for forming new long term memories, but the memories themselves are stored elsewhere.

Roger's happy-go-lucky disposition is also not too unexpected, given that he suffered bilateral damage to the ventromedial prefrontal cortex (vmPFC). Last year I wrote about a study from the same Iowa team finding that damage to this area seems to protect against depression. And this is the same region which was targeted by the infamous prefrontal lobotomies of the 40s and 50s - which, for all their ethical shortcomings, sometimes did seem to relieve people of mental anguish.

For me, Roger provides two main lessons, both rather satisfying ones. Firstly, even after losing large parts of the brain, life goes on. The brain is modular, and we can live without many of the modules. And secondly, if our emotional circuitry is damaged, we generally feel better, rather than worse. To put it another way, perhaps, happiness is our default state, and emotions just have a habit of getting in the way.

ResearchBlogging.orgFeinstein, J., Rudrauf, D., Khalsa, S., Cassell, M., Bruss, J., Grabowski, T., & Tranel, D. (2009). Bilateral limbic system destruction in man Journal of Clinical and Experimental Neuropsychology, 1-19 DOI: 10.1080/13803390903066873

Monday, September 21, 2009

Asia's 1st Life-sized Bread Race Car! - RT/WW



Executive Chef Abraham Tan (Royal Plaza On Scotts) and his team used 14 litres of water, 15 kg of yeast, 2 kg of salt and 10.8 litres of food varnish to create Asia's first life-sized Bread Race Car!



A competition was held to guess the weight of flour used. The answer will be announced at the end of September.



This bread race car is more than 4.24 m long, 1.78 m wide and 1.03 m high.






The life-sized race car wheel is created out of a variety of breads: Squid ink Focaccia Bread, Soya Milk bread, Laugen bread and Ciabatta.



Chef Abraham Tan used the following types of bread to create this life-sized bread race car :

1. Honey Milk Bread         12. Squid ink Focaccia Bread
2. Potato Bread                 13. Soya Milk bread
3. Milano Grain                  14. Laugen bread
4. Curry Roll                      15. Ciabatta bread
5. 9 Coreals Roll                16. Dark Sour Rye Bread
6. Hard roll                        17. Sesame Kaiser Roll
7. Onion Roll                     18. Rustico Baguette
8. Farmer Bread                19. Wholemeal Baguette
9. Country Bread               20. French Baguette
10. Chinese Bun                21. Focaccia Bun
11. Soft Bun                      22. Swiss Farmer Bread

Asia's 1st Life-sized Bread Race Car will be on displayed at Royal Plaza On Scotts lobby until 27 September 2009.




First Commenter - Liza

I ate mould.

I was running late for work and figured I'd have time to pick up some juice and a muffin at the convenience store right by my office before I got in. I plucked up an unsuspecting, fat and greasy looking blueberry muffin (450 yummy calories...or so I thought) and sprinted up to my desk.After opening all the requisite web sites, emails, and various other windows, I tore the packaging open and

Encephalon #76 - Call for Submissions

Neuroskeptic will be hosting the 76th instalment of ENCEPHALON, the regular neuroscience and psychology carnival. So get writing, or get submitting things you've already written, about the brain, the mind, and all that kind of thing.

As ever, please e-mail submissions (up to 3 posts) to encephalon dot host at gmail dot com, by the end of this Sunday 27th September!

Saturday, September 19, 2009

Why Do We Sleep?

Why do we sleep? Because otherwise, we'd always be doing stuff.

This is the theory advanced by UCLA sleep researcher Jerome Siegel (website) in a new paper, Sleep viewed as a state of adaptive inactivity (free pdf). It's part of a Nature Reviews Neuroscience special issue on the evolution of the nervous system. Siegel proposes that the evolutionary function of sleep is simply to ensure that animals are only active when the benefits of movement (mostly access to food, and mates) outweigh the costs (activity burns calories, and puts you at risk of predation or accidents).

Sleep, in other words, is our equivalent of the inactive states into which most living things, even plants, periodically enter when it suits them. Even (deciduous) trees spend the cold, dark half of the year doing not very much. In Siegel's view, this is their equivalent of sleep.

This theory stands in contrast to the idea that sleep has a restorative function - that animals need to sleep, because some kind of important biological process can only occur while we're sleeping. This idea is intuitively appealing - it feels like we benefit from sleep, and at least in humans sleep deprivation has many well-documented negative effects.

But, as Siegel points out, we're far from any kind of a consensus on what the biological function of sleep is. It's generally assumed that there is one, and a great many have been proposed - he lists some, ranging from that sleep is important for the formation of new neural connections, to the idea that sleep is needed to reverse cellular damage caused by oxidative stress (interestingly, Siegel himself contributed to one of the papers he gives as a reference for that idea).

If a vital restorative function of sleep were to be conclusively identified, Siegel's theory would obviously be disproven. On the other hand, if Siegel is right, several things should be true. Firstly, the proportion of time that an animal spends asleep should be directly proportional to the amount of time that it is useful for it to be active.

Siegel argues that this is what we find. The big brown bat for example is the doziest of all mammals, sleeping for 20 hours per day. But it wouldn't benefit from being awake any more, because the insects it feeds on are only active for a few hours at dusk. If it were flying around during the day, it would just be wasting energy (and risking becoming lunch for a bird.)

By contrast, he says, some marine mammals (cetaceans, dolphins and whales) never sleep at all. In land mammals, sleep consists of distinct periods of neural activity such as REM and slow wave sleep. Neither, however, occurs in cetaceans. They do show a kind of neural activity called Unihemispheric Slow Waves (USWs). But these are confined to one half of the brain at a time. It's often said that this is "half the brain going to sleep". However, the animals remain moving normally, and are able to avoid obstacles, during USWs. It's not as if only half their body remains awake. As such, Siegel says, the USW state is not sleep.

If it's true that there are animals which never sleep, this is strong evidence for Siegel's theory, and against the idea that sleep plays a vital role. But not everyone agrees with his claim that dolphins and whales don't sleep. See, for example, this 2008 open-access paper, Is Sleep Essential?, which calls Siegel's theory of sleep the "null hypothesis" and then proceeds to criticize it.

In particular, the authors claim that dolphins do sleep, albeit with only one half of their brain at a time, and they make the interesting point that "the very fact that dolphins have developed the remarkable specialization that is unihemispheric sleep, rather than merely getting rid of sleep altogether, should count as evidence that sleep must serve some essential function and cannot be eliminated."

At this point the debate becomes highly technical. The sleep behaviour and neural activity of marine mammals is hardly easy to research, and it looks as though more evidence is needed before we can know for sure whether they sleep or not. This is one of those seemingly trivial questions which could end up deciding between two theories with enormous implications. There are quite a lot of them in science. We don't yet know why we sleep. But the answer may lie with the dolphins.

Link: More recently, I asked Why do we dream?

ResearchBlogging.orgSiegel, J. (2009). Sleep viewed as a state of adaptive inactivity Nature Reviews Neuroscience, 10 (10), 747-753 DOI: 10.1038/nrn2697

Friday, September 18, 2009

Puff the Illusionary Dragon

There's a lot of interest in visual illusions at the moment thanks to an excellent article over at Seed, This Picture Is Not Moving.



A while back I wrote about the Hollow Face Illusion in which a hollow (concave) mask of a face appears to be a solid (convex) face and I posted a seriously freaky video featuring Charlie Chaplin. But reader "Jake" just pointed out an even better example of the same illusion, the Paper Dragon.

See the video above. If you like what you see, you can make your own paper dragon by printing out this .pdf here. It only takes 10 minutes, scissors and a bit of sticky tape. I highly recommend it, the effect is astonishing - it really looks as though the dragon's head is moving. You may need to close one eye to get the full experience. (The dragon was designed by ThinkFun).

The dragon, like the Charlie Chaplin mask, is an example of the "depth inversion" effect. Our visual system assumes that objects are convex, rather than concave, especially when those objects are familiar things like faces.

In my opinion the most interesting thing about the phenomena, and indeed with all illusions, is that concious belief cannot override the effect. I know that the dragon's head is concave, I folded it up and stuck it together myself. Yet I still see it as convex. This is strong evidence for the modularity of mind. But that's another story.

Dara Turns Lives Upside-down - PhotoHunt

PhotoHunt theme : Upside-down




I was invited to a private screening of the movie, DARAH (Indonesian title which means Blood. It's International Title is Macabre) at Goodwood Park Hotel's former Thumper Bar.





I thought I had gone to the wrong venue when I entered and saw this......





Huh!?

Gosh! It was an old, deserted building. There was this horrible musty smell throughout the room and it stuck onto my clothes and hair after that.






An eerie place to hold a horror movie preview. We were half-expecting killers to appear. Before the movie commenced, we were ordered
advised not to cover our eyes; to scream our hearts out and enjoy the movie. In case anyone wants to walk out, all the doors have been locked. *pretends to tremble*

hehe.......




Eric Khoo addressing his guests before the movie.

We sat in pitch darkness. I dared not used flash for my camera in case the organisers got provoke and turn on me. I think I was the only one who dared to take pictures. *gulp*

******************* ooooo OOO ooooo ******************

Darah tells the story of a group of friends who are lured to a deserted country house when they stop to help a young woman Maya (Imelda Therinne) who claims to have been robbed.

The mother Dara (Shareefa Daanish) insists they stay for dinner. It turns their lives upside-down! They are drugged and woke to find themselves tied up. Horrified, they witnessed the slaughtering of their friends... one by one.

It is a bloodbath! What I saw was so horrendous and sickening! Limbs and necks are broken; bodies are decapitated, stabbed, shot, burnt, chainsawed! It's blood, blood and more blood.... everywhere!

Eric Khoo, one of the Executive Producers for Darah, told me it is categorised M18. I think there will be some censored scenes in the cinema version. What I saw was too gory! :P

I'm awestricken with Indonesian actress Shareefa Daanish who plays the indestructible mother. She sent shivers down my spine when she screamed "Bring me their heads!" and brandished a chainsaw at the beautiful heroine Ladya (Julie Estelle). Yes, they cast beautiful people in a horror movie. Another eye-candy is actor Arifin Putra who plays the creepy and equally indestructible son Adam.

Darah has been creating rave reviews and praises in Puchon International Fantastic Film Festival 2009 where Shareefa Daanish won Best Actress for her portrayal as the sick Dara. *applause*

Darah will hit the cinemas on 8th October 2009.

Let the slaying begins!

A Gorylah Pictures, MediaCorp Raintree Pictures (Singapore)/Merah Prod., Guerilla Visual Movement, Nation Pictures (Indonesia) production. Produced by the Mo Brothers. Executive producers, Eric Khoo, Mike Wiluan, Charles Teo, Daniel Yun. Directed, written by the Mo Brothers (Timo Tjahjanto, Kimo Stamboel).










First commenter - oceanskies

Wednesday, September 16, 2009

fMRI Gets Slap in the Face with a Dead Fish

A reader drew my attention to this gem from Craig Bennett, who blogs at prefrontal.org:

Neural correlates of interspecies perspective taking in the post-mortem Atlantic Salmon: An argument for multiple comparisons correction

This is a poster presented by Bennett and colleagues at this year's Human Brain Mapping conference. It's about fMRI scanning on a dead fish, specifically a salmon. They put the salmon in an MRI scanner and "the salmon was shown a series of photographs depicting human individuals in social situations. The salmon was asked to determine what emotion the individual in the photo must have been experiencing."

I'd say that this research was justified on comedic grounds alone, but they were also making an important scientific point. The (fish-)bone of contention here is multiple comparisons correction. The "multiple comparisons problem" is simply the fact that if you do a lot of different statistical tests, some of them will, just by chance, give interesting results.

In fMRI, the problem is particularly severe. An MRI scan divides the brain up into cubic units called voxels. There are over 40,000 in a typical scan. Most fMRI analysis treats every voxel independently, and tests to see if each voxel is "activated" by a certain stimulus or task. So that's at least 40,000 separate comparisons going on - potentially many more, depending upon the details of the experiment.

Luckily, during the 1990s, fMRI pioneers developed techniques for dealing with the problem: multiple comparisons correction. The most popular method uses Gaussian Random Field Theory to calculate the probability of falsely "finding" activated areas just by chance, and to keep this acceptably low (details), although there are other alternatives.

But not everyone uses multiple comparisons correction. This is where the fish comes in - Bennett et al show that if you don't use it, you can find "neural activation" even in the tiny brain of dead fish. Of course, with the appropriate correction, you don't. There's nothing original about this, except the colourful nature of the example - but many fMRI publications still report "uncorrected" results (here's just the last one I read).

Bennett concludes that "the vast majority of fMRI studies should be utilizing multiple comparisons correction as standard practice". But he says on his blog that he's encountered some difficulty getting the results published as a paper, because not everyone agrees. Some say that multiple comparisons correction is too conservative, and could lead to genuine activations being overlooked - throwing the baby salmon out with the bathwater, as it were. This is a legitimate point, but as Bennett says, in this case we should report both corrected and uncorrected results, to make it clear to the readers what is going on.

Tuesday, September 15, 2009

HP Ignites ENVY - Nothing but HP for me event


Mr See Chin Teik, Senior Vice President, Personal Systems Group, HP Asia Pacific & Japan unveiling HP Envy

HP invited journalists from the region to its grand "Nothing but HP for me" event at Amara Sanctuary in Sentosa on 15th September 2009. As one of the 'more prolific bloggers' in Singapore, I was one of the privilege few invited to this media event which showcased HP's latest upcoming netbooks, notebooks and desktops.

HP Raises Envy in Thin & Light Computing

HP unveiled not one... not two ..... but a mind-boggling line-up of thin and light notebook PCs!

HP's partnership with fashion designer Vivienne Tam is brilliant and a huge success. I love her awesome designs. HP’s latest collaboration is with world–renowned Dutch industrial designer, Tord Boontje.

The Limited Edition HP Mini by Studio Tord Boontje is a breakthrough in design innovation. It comes with the world’s first three-dimensional PC surface technology – HP Imprint 3D.




Ms Chua Hwee Koon, Vice President, Mobile Business Unit, Personal Systems Group, HP Asia Pacific & Japan holding Boontje’s design

HP Imprint 3D brings great detail and unique depth to Boontje’s design of flora and endangered animals. Extending the design experience beyond the surface, this model also comes with 15 wallpapers, customized Stardock MyColors™ desktop theme and custom screen saver all designed by Boontje. - HP press release


For readers who ask me what a media event for a new product launch is like, the ones (top brand names) I attended are usually grand and elaborate. The venues they select are either unique or exclusive. I mingle with the professionals from the media industry and some are from other countries.  I get to rub shoulders with the company's top management. :P

There would be a sumptious buffet spread or a sit-down dinner, and free flow of beverages including beer, wines, champagne.  

HP provided transport for me to and from this event right up to my door-step. VIP treatment.... and I'm only a mommy blogger.

Oh.... invited guests get door gifts and a discount on the company's new products. :)

'Nothing but HP for me' media event

HP made me an offer I cannot resist. I bought a HP PC (I would love to have the mini notebook offer as well *wink wink* ) ...... to be revealed in October 2009. :P



More photos of this event in my FaceBook. 

First Commenter - yenjai

Monday, September 14, 2009

Free Furniture and How to Get It!

Following up from my previous post, I would like to casually mention that we successfully nabbed our new two-bedroom apartment! Making all the initial payments are really quite gut-wrenching but you just have to keep telling yourself that if you keep things as clean as can be, you'll get back that $3,000 deposit in a year.... sigh.I think that's a bit of wishful thinking really, but we'll

Ramly Burgers - RT/WW


This is one burger that I look forward to eating at the annual Geylang Serai Hari Raya Bazaar. It's Ramly burger!!. .



This year, this stall's Ramly burgers are the best!



Besides adding curry powder and mayonaise sauce to their burgers, there is this brown sauce. I wonder what sauce is that?
*takes a huge bite*




First Commenter -day-dreamer

Sunday, September 13, 2009

YouGov Reply

On Thursday, I wrote about British polling company YouGov, in a follow-up to an earlier post about modern Britain's fondness for opinion polls. YouGov's Co-Founder, Stephan Shakespear, has written a response, which I've posted below.

Stephan makes a strong case that YouGov's polling methods are at least as good, or better, than those of other polling companies. I don't disagree, and I don't have any suggestions as to how they could be improved. In the political sphere, YouGov are widely regarded as the most credible British pollsters, and as Stephan says, they have an excellent record of accuracy in that area. Their popularity is why I chose them as the focus of my piece.

In my post, I did rashly suggest that YouGov's internet-based panel approach might be less representative than a random phone sampling method. But as Stephan says, such a system has plenty of serious problems of its own: "There’s no such thing as a random sample for any kind of market research or polling. There is only random invitation, but since the overwhelming majority of people decline the invitation (or don’t even receive it because they are out when the phone rings...) the resulting sample cannot be random. And it is clearly skewed against certain types of people ... as well as different temperaments..."

As he goes on to say, what YouGov do is inherently difficult - "It’s very hard to know with certainty what the population as a whole thinks about a particular topic, by any method." And this was my essential point: YouGov polls, like all polls, are not an infallible window into public opinion. They could be perfectly accurate - but we don't have any way of knowing how accurate they are, except when it comes to elections, which is a special case.

My issue was, and is, with those who commission opinion polls as a form of advertising, and those who try to use them to demonstrate things which they simply cannot do. Very often, these are the same people. The example I used in my original post was of a poll conducted by a company who run private health and fitness clubs. The message was that British people are incredibly unfit and lazy. Amongst other things it reported that 64% of parents are "always" too tired to play with their children. I don't believe that. I don't think an opinion poll is a good way of measuring laziness. Physical fitness is a vital public health issue, but this is just silly.

It's not clear if that was a YouGov poll, but this one was: 75% of Britons text or blog while on the toilet, which puts us at risk of haemorrhoids, according to a poll commissioned by the makers of trendy, expensive 'probiotic' yoghurt, Yakult. That got Yakult mentions in The Telegraph, The Scotsman, The Metro and The London Paper. I could go on.

Of course we can't blame polling companies for what their clients do with their data. But a healthy scepticism of this data is part of the reason why I'm so disappointed at the number of newspaper articles, usually based very closely on press releases (like Yakult's), based on such polls. It's not YouGov's fault, and I'm sure most of the research YouGov do is not like this. But it's a problem. It's lazy journalism, and it's a poor substitute for serious, informed debate about health and social issues.

Anyway, here's Stephan Shakespear's reply:

"As you must realise, there’s no such thing as a random sample for any kind of market research or polling. There is only random invitation, but since the overwhelming majority of people decline the invitation (or don’t even receive it because they are out when the phone rings, or they don’t pick up their phone because they screen calls, etc) the resulting sample cannot be random. And it is clearly skewed against certain types of people (younger people, busier people, etc), as well as different temperaments (most people won’t willingly give up their time to answer surveys: remember that they tend to be quite long, and not usually on very interesting subjects. Would you stop in the street on your way to work for someone with a clipboard? Would you say ‘yes’ when you are called in the middle of making supper for your kids?)

When researchers do manage to talk to someone, there is no way of knowing whether the answers respondents give to the questions reflect their true thinking. Indeed, as a neuroscientist will be quick to point out, it may not be easy to define what their “true thinking” is, because they may never before have thought about the topic they are being asked about. It may well be that ten minutes after the interview, they think differently about it. Or maybe they were lying, either to the interviewer or to themselves. Maybe they were trying to please the interviewer with the answer they thought was wanted. Maybe they want to appear more reasonable than they really are.

So it’s very hard to know with certainty what the population as a whole thinks about a particular topic, by any method. In fact it’s impossible even if one has the latest neuropsychology techniques at one’s disposal. Nowhere in your piece do you discuss any of these issues which apply to all forms of opinion research, under any conditions. Comparison with other methodologies is important, because we must do the best we can when conditions dictate imperfection.

To repeat: all methodologies include selection bias (self-selection to participate in a panel is not essentially different from the overwhelming self-de-selection that applies to random-interruption methods), and all have motivational biases (anyone who wants to spend their time giving opinions is different in some way to people who don’t; why should payment mean a ‘financial interest’ that skews opinions? Are the volunteers used for neuroscience not usually rewarded, often financially? Surely non-payment skews the motivation too?)

For the record, at YouGov, we take a lot of care to recruit people to our panel by a variety of methods. The great majority are proactively recruited, they do not find their own way to the panel. They are recruited from a variety of ‘innocent’ sources to maintain as good a demographic balance as we can. But we do not claim random selection - as stated above, no research agency can possibly enforce participation from a random selection, it’s impossible. It was precisely because of our acknowledgement that true random samples are impossible that we say we ‘model’, we do not merely ‘measure’ – something which most of the industry now agrees with. Because we are explicit about this, and because we have historical data on our respondents, we can model by more variables. In other words, we are more scientific, not less scientific, than the methods which, by implication of your omissions, you prefer. We know more about our sample, so we can compare them with the general population in a more sophisticated way; and we have no interviewer effect; and respondents can think a little longer about their answer. So we think that makes for better data. In fact, wherever our data can be compared to real outcomes, we have a fantastic record.

You say that our record of accuracy in predicting elections does not mean we are accurate in other things. It is true that most areas of public opinion cannot be proved, by any method, and therefore we cannot prove it either. But it’s surely better to use a methodology that has proven its accuracy in areas that can be proven, rather than one that was found to be wrong, no? YouGov has the best record of accuracy in predicting real outcomes; most recently the Euro elections and the London Mayoral election. You may remember other pollsters had Ken Livingstone beating or neck-and-neck with Boris Johnson. We said Johnson would win by 6%. He won by 6%. Would you rather trust a company that gets the provable things right, or a company that gets them wrong? Does your ‘science’ tell you that methodologies which get the wrong political prediction are more likely to be right in other areas? If so, please explain further.

As it happens, the vast majority of the revenue for YouGov comes from market research for companies who do not publish the results in the media, companies which rely on the accuracy of our descriptions and predictions of consumer behaviour for their future planning. You might want to credit them with some kind of quality-control, if only in their self-interest.

Given that we all acknowledge the difficulty of knowing precisely the percentage that think this or that about some topic they may rarely have thought about, what is your suggested better course? As it is ultimately impossible to know what a single person “thinks”, let alone an entire population, maybe we should attempt nothing, report nothing? Would it be better if there were no data available, only the anecdotal publications of bloggers?

We don’t let it rest. We constantly experiment - with, for example, deliberative methodologies to try to measure how people change their thinking when they consider a matter more, when they are given access to more information, etc. Our panel methodology allows us to use very large (20,000+) randomly-split samples where we seek responses from each split to very slightly altered inputs, controlling for all but a single variable. Even you might agree that our methodology here is of a piece with that of your fellow scientists, some of whom we’ve consulted. We are able to do scientific things with our methodology that other, random-digit-dialing methods can’t, or at least can’t do in an affordable way. You might want to credit us with our serious approach to methodology, rather than slag us off in your most unscientific manner.

Stephan Shakespeare, Co-Founder and Chief Innovation Officer, YouGov"

Saturday, September 12, 2009

Most People Experience "Mental Illness" By Age 32

Mental illness: how common is it? A popular answer is one in four - 25% of people will experience it at least once in their lives. In fact, most published research suggests that the lifetime rate is higher, around 30-50%, in Western nations.

That's a lot. But even this may be a serious underestimate, according to a new paper, How common are common mental disorders? The study compared the proportion of people reporting mental illness under two different research methods: retrospective and prospective.

Retrospective means asking people to think back and remember whether they ever have felt a certain way. A prospective study, however, recruits people and then follows them up for a certain length of time, asking them how they feel at regular intervals.

The obvious advantage of prospective studies is that there is less chance of forgetting. In a retrospective study, people are required to remember how they were feeling years, or even decades, ago. Human memory just isn't that good. A prospective study requires some remembering, as people are generally asked to report how they've felt over the last year, but this is clearly less problematic.

The prospective study in question here included 1,000 people from Dunedin, New Zealand. The volunteers were followed from birth to age 32, and were interviewed at ages 18, 21, 26 and 32. The results were compared to three large retrospective lifetime studies, two American and one from NZ. (1,2,3).

50% of the Dunedin prospective cohort reported at least one "anxiety disorder", 41% reported "depression", 32% confessed to "alcohol dependence" and 18% to "cannabis dependence". (Those were the only conditions studied.) For some reason, we're not told how much overlap there was, but even assuming there was a lot, well over half of all the cohort will have experienced at least one disorder. If the overlap was low, it could be almost all of them. And remember, this is just up to age 32. And there still may have been some forgetting...

Compared to the retrospective studies, these rates are all about twice as high. What does this mean for psychiatry?

First, it suggests that retrospective studies, which are by far the most common, are flawed. People just tend to forget a lot of "mental illness" when asked to remember across the lifetime. More evidence for this comes from the fact that the ratio of past-year to lifetime reported disorders was 38% in the prospective study compared to about 60% in the retrospective ones.

But there's a more profound implication. A growing number of critics have argued that the very high reported lifetime rates of mental disorders mean that the way most psychiatrists diagnose mental illness is flawed. The "Bible" of modern psychiatric diagnosis is the Diagnostic and Statistical Manual (DSM) of Mental Disorders of the American Psychiatric Association. DSM diagnostic criteria were used in the studies in question here.

These results suggest that DSM diagnoses are even more common than previously believed, which only strengthens the critics' case. According to DSM criteria, at least 40% of people experience "Major Depressive Disorder" by age 32.

In which case, what is it? A fairly usual part of human life. So, calling it a disease and treating it with drugs or therapy seems rather presumptuous. Especially since so many people who "suffer" from it manage to not only get over it, but actually forget it ever happened. (Of course, this shouldn't be taken to mean that real, serious clinical depression doesn't exist.)

The authors conclude - listen carefully -
This article is uninformative (and agnostic) about the validity of diagnoses as defined by DSM-IV ... [rather], objections voiced to surveys’ higher than expected lifetime prevalence of disorder are objections to prevalence that is only half what it could be in reality...

Researchers might begin to ask why so many people experience a DSM-defined disorder at least once during their lifetimes, and what this prevalence means for etiological theory, the construct validity of the DSM approach to defining disorder, service-delivery policy, the economic burden of disease, and public perceptions of the stigma of mental disorder.
That hammering sound you hear is another nail sealing the coffin of DSM's credibility. If many* DSM "disorders" are simply descriptions of normal parts of human life, we need to take a long, hard look at those "disorders", and rethink whether they need to labelled and treated as medical problems.

The newest edition of DSM, DSM-5, is currently in development. This would seem like a great opportunity to do just that. Unfortunately, the development process is rapidly degenerating into farce. If DSM-5 does not address the issues raised here, many people will be tempted to give up on DSM entirely.

* Not all: the great majority of people will never meet criteria for schizophrenia or bipolar disorder, for example.

ResearchBlogging.orgMoffitt, T., Caspi, A., Taylor, A., Kokaua, J., Milne, B., Polanczyk, G., & Poulton, R. (2009). How common are common mental disorders? Evidence that lifetime prevalence rates are doubled by prospective versus retrospective ascertainment Psychological Medicine DOI: 10.1017/S0033291709991036

Friday, September 11, 2009

Execution by Electric Chair - PhotoHunt

PhotoHunt theme : Electric



The Electric Chair

I love to bring my students to Singapore Science Centre because of its interactive exhibits. One exhibit that provides the children the most fun and unforgetable experience is this Electric Chair.

But it is neither fun nor interesting for the criminals who were sent to the electric chair. :(

Harold Brown invented the electric chair. On 6th August 1890, the electric execution of the first man was William Kemmler of Buffalo, New York. He was guilty of butchering his mistress with an axe.

As a group of doctors and reporters watched this historic occasion, Kemmler was jolted for 17 seconds. It failed to kill him. He was unconscious but still breathing.

Embarrassed prison officials electrocuted him again for 70 seconds. As the electrodes seared his head and arms,Kemmler thrashed and convulsed. The room was filled with the smell of burning flesh. Some witnesses fainted, while others fled the room. The killing took 8 minutes.

Yikes. That's a painful way to die. :(