2012-10-02

This is how science works


http://blogs.scientificamerican.com/scicurious-brain/2012/09/25/ignobel-prize-in-neuroscience-the-dead-salmon-study/

The basic premise is that a bunch of scientists put a dead salmon in an fMRI and demonstrated brain activity.

Yes, in a dead, frozen salmon.

So in the final results, the authors compared the normal multiple comparisons, with the multiple CORRECTED comparisons. When they used the multiple corrected comparisons, the dead salmon showed nothing. When they did the multiple comparisons without the correction, the salmon showed significant increases in “activation”, coincidentally, in the brain and spinal cord. This shows the importance of correcting for multiple comparisons and avoiding false positives


The original poster almost didn’t make it to a conference, but when it did, it made a major splash, and reactions were very positive. Some people like to use the salmon study as proof that fMRI is woo, but this isn’t the case, it’s actually a study to show the importance of correcting your stats.

And the poster, and the paper that was eventually published, may have had an effect on the field. The authors note that at the time the poster was presented, between 25-40% of studies on fMRI being published were NOT using the corrected comparisons. But by the time this group won the Ignobel last week, that number had dropped to 10%. And who knows, it might, in part, be due to a dead fish.

Yes, that's right, a frozen fish - and the analysis of it - may have improved medical science.

The takeaway point, though is that you can do your data collection correctly but screw up your  analysis and still end up with a bad result.

2012-08-06

Or, sometimes, you're looking in

Curiosity (inside its sky crane) as it parachutes down to the surface of Mars, as seen from the Odyssey orbiter
Off the planet, past the moon, across space, through the atmosphere, under the parachute, released from a sky crane...

... nothin' but net.

2012-06-04

Standing

So, you're some unimportant, average person in your city. You know there's some kind of protest or sit-in going on nearby - you walk through the park regularly, and it's been on the news - but you're not participating. You may agree, you may disagree, doesn't really matter.

You've been out buying groceries, and on your way back, you decide to cut across the square like you always do. As you cross the street, you see a line of tanks - of your own government's military - heading away where the protestors (mostly students, but almost all citizens) were. Where they'd just killed hundreds if not thousands.

What do you do?

What kind of a person does it take to go from a casual walk home to standing in front of a moving line of tanks? What went through his mind? We don't know his name, his history, his motivations, or anything - all we know is what was caught on film: a man standing alone on a road.

If it happened in your city - if you were walking along and saw a line of tanks heading towards a protest nearby - what would you do? Would it matter who the protestors were? If they were democratic students or religious fundamentalists or just a bunch of people having a bad day? Would you hesitate? Would you keep walking? Or would you stand them down?

What kind of person are you?

(As a note, I'm explicitly not using certain words and phrases here. The events of that day twenty-three years ago are still heavily censored in that country. It has been written out of history books, is banned from all forms of media, and was the cause of books and such being burned. The people who most need to know about the events that happened - that nation's youth of today - are officially forbidden from learning about it. Think about that a while.)

2012-03-29

Fighting Back

How many times have you found yourself arguing for a position you didn't really support merely because someone had tried to impose upon you the opposite position?

Classically, this is the behavior of teenagers - in extreme cases classified as "oppositional defiance disorder" - but even adults experience this kind of inherent oppositional reaction when we feel our independence is being challenged.

In psychology, this is known as "psychological reactance theory". From Psycholopedia:
Psychological reactance is an aversive affective reaction in response to regulations or impositions that impinge on freedom and autonomy (Brehm, 1966, 1972, Brehm & Brehm, 1981; Wicklund, 1974). This reaction is especially common when individuals feel obliged to adopt a particular opinion or engage in a specific behavior.

Specifically, a perceived diminution in freedom ignites an emotional state, called psychological reactance, that elicits behaviors intended to restore this autonomy (Brehm, 1966, 1972, Brehm & Brehm, 1981; Wicklund, 1974). Reactance, for example, often encourages individuals to espouse an opinion that opposes the belief or attitude they were encouraged, or even coerced, to adopt. As a consequence, reactance often augments resistance to persuasion (Brehm & Brehm, 1981). Reactance was proposed to explain many common examples of resistance in society, such as the adverse effects of prohibition.

Yes, this is a real, traceable, verified concept: an individual is more likely to be confrontational when s/he perceives that his or her freedoms are being impinged. It doesn't matter why or whether or not they agree with the underlying principles: merely the act of feeling confined, physically or mentally, induces a basic "fight or flight" syndrome that comes out as oppositional defiance.

Keep this in mind both as you watch your own behavior and as you watch how others respond to you. If you know you are predisposed to a negative response in certain situations, you can have mitigate that response to some degree and prevent yourself from getting into confrontations you don't necessarily want to have. You can also strive to prevent others from feeling the same kind of confinement and, thus, hopefully reduce their tendency to be confrontational in return.

(Sorry for the long lag between posts; I'll try to get at least one a month up.)