I know you all know not to rely exclusively on the Wikipedia…

Here’s today’s example of why:

Up until a week ago, here is something you could have learned from Wikipedia:

From 1640 to 1641 the might of colonial Portugal clashed with India’s massive Maratha Empire in an undeclared war that would later be known as the Bicholim Conflict. Named after the northern Indian region where most of the fighting took place, the conflict ended with a peace treaty that would later help cement Goa as an independent Indian state.

Except none of this ever actually happened. The Bicholim Conflict is a figment of a creative Wikipedian’s imagination. It’s a huge, laborious, 4,500 word hoax. And it fooled Wikipedia editors for more than 5 years.

Full story, via the always-marvelous Sara Harvey.

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Crossmodal processing of vision and olfaction

Crossmodel perceptual illusions and effects are long-established, but they usually involve the relationship between vision and audition (like in the McGurk effect).

I’ve seen more of these involving other modalities lately, though. Last year’s Best Illusion of the Year winner was a vision/proprioception illusion:

And a recent paper in J Neuroscience uses olfaction to affect binocular rivalry.

In their main experiment, Zhou and colleagues showed people rival pictures of a rose and a banana at the same time. While doing this, they gave their volunteers the smell of a rose, and people became more likely to see the image of the rose.

When they gave them the smell of the banana, they were more likely to see the banana.

From NeuroDojo.

A (bit of a) mirror neuron smackdown

I’ve been thinking about mirror neurons, lately, since a talk by a woman whose work presumes their existence and importance. Mirror neurons are the Higgs Boson of neuroscience, a phenomenon that is given greater significance by people outside the field than by people inside.

Via @scicurious, this article at Psych Today reminds us to rein in some of the hype:

A non-player tennis fan who’s never held a racket doesn’t sit baffled as Roger Federer swings his way to another victory. They understand fully what his aims are, even though they can’t simulate his actions with their own racket-swinging motor cells. Similarly, we understand flying, slithering, coiling and any number of other creaturely movements, even if we don’t have the necessary motor cells to simulate them.

Article at Psychology Today

“they concealed themselves under beds in students’ rooms”

The consistently-fascinating Mind Hacks has a story today about a really pretty sketchy study from 1938, in which researchers were trying to measure some aspects of student conversation without inducing any reactivity.

In order not to introduce artifacts into the conversations, the investigators took special precautions to keep the subjects ignorant of the fact that their remarks were being recorded. To this end they concealed themselves under beds in students’ rooms where tea parties were being held, eavesdropped in dormitory smoking-rooms and dormitory wash-rooms, and listened to telephone conversations.

The rest of his write-up is here.

Neurosciencyness is the new truthyness

Got off the train this morning and noticed a new (ish? I’m not super attentive to these) ad:

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L-theanine is an amino acid that crosses the blood-brain barrier and has been shown to increase alpha-band EEG activity. The logic here seems to be the same as that in things like the games that come with the Mindwave biofeedback system:  since alpha-band EEG oscillations occur when people are relaxed, then manipulations that increase in alpha-band activity must be increasing relaxation. (Nobody, to my knowledge, uses this logic while also accounting for the many other cognitive activities that increase alpha-band activity, like actively remembering things, or attending to one object in a crowded field, that do not seem to have much at all to do with relaxation. Brains are, unfortunately, complex, interconnected, emergent systems, and cause and effect are rarely straightforward.)

Neuro seem to have a whole range of these drinks, each with a different additive, a neurosciency gibberish explanation of why that additive will change your brain function, and a different targeted effect. A few years ago, a paper demonstrated that people are much more willing to accept explanations (even bad explanations) if a neurosciency clause is included. Shortly afterwards, another group showed that people are more likely to accept neurosciency explanations if the brain activity being discussed was shown on realistic brain pictures, as opposed to abstract images or bar graphs.

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Besides calling their brand “neuro”, these guys have a cute little “EEG activity in the brain” logo, and their website has the slogan “light it up”. Scarily impressive use of the metaphors and descriptors that are used to describe localized neural activity, even by those of us who should know better.

When I posted these to Facebook this morning, one friend said, “I’m not sure whether to be skeptical about their ability to actually modify neurotransmitter availability, or seriously concerned about people actually changing their brain chemistry in untested and unregulated ways.” I think this pretty well sums up my feelings too.

Understanding (and quantifying) uncertainty

Dave Kleinschmidt has some commentary on the Nate Silver fangirl/boy-ing that many of us quantitative types have been engaging in for the last week. 

My tribe—the data nerds—is feeling pretty smug right now, after Nate Silver’s smart poll aggregation totally nailed the election results. But we’re also a little puzzled by the cavalier way in which what Nate Silver does is described as just “math”, or “simple statistics”. There is a huge amount of judgement, and hence subjectivity, required in designing the kind of statistical models that 538 uses. I hesitate to bring this up because it’s one of the clubs idiots use to beat up on Nate Silver, but 538 does not weight all polls equally, and (correct me if I’m wrong) the weights are actually set by hand using a complex series of formulae.

The point is that the kind of model-building that Nate Silver et al. do is not just “math”, but science. This is why I don’t really likethat XKCD comic that everyone has seen by now. Well I like the smug tone, because that is how I, a data scientist, feel about 538′s success. That is right on. But we’ve known that numbers work for a long time. Nate Silver and 538 is not just about numbers, about quantifying things. Pollsters have been doing that for a long time. It is about understanding the structured uncertainty in those numbers, the underlying statistical structure, the interesting relationships between the obvious data (polling numbers) and the less obvious data (economic activity, barometric pressure, etc.) and using that understanding to combine lots of little pieces of data into one, honkin’, solid piece of data.

When I teach stats, or talk about stats in my other classes, I try to hammer on this point about uncertainty. As scientists, we're dealing with noise in our data from all kinds of places. Is the sample under study "weird" in some way? Is our measure noisy? How noisy? How variable are people? Why? Does the time of day/day of week/week of year when people are tested matter? We can estimate how much uncertainty (what statisticians call "error") comes from each of these sources, and try to figure out if there's a structure/pattern underneath the noise, but in order to do that successfully you have to really think about the sources of the error. I think every time I've been really screwed over by an experiment, it's been because there was a source of variability or a kind of variability that I just didn't expect.

Then I looked a little closer and realized it was Tim Minchin. That changed things a lot. It’s nine-minutes of sheer unadulterated brilliance. Watch it. If you only watch one nine-minute animated beat poem in your life (and one may be all that I have in me), this is the one to watch. It tells the story of a dinner party where he confronts a credulous hippie. Good stuff.

via allbleedingstops.blogspot.com