Does Brain Imaging Make You Dumb?

I'm not talking about sticking your head in fMRI scanner, which, so far as anybody can tell, is perfectly safe. (Unless you happen to have a pacemaker or pieces of shrapnel in your head, in which case you might want to give the whole procedure a miss).

No, I'm talking about what happens to people when they read about studies of brain imaging. Every 29 seconds or so, some scientist publishes a new study using brain imaging. And some magazine editor gets very excited. Aha, look at the cool color pictures! Look how the brain "lights up" when people look at pictures of Hilary versus Obama. This is your brain on crack, and this is what your brain looks like during orgasm.

There's no denying that the pictures look cool. But do they actually tell us anything? Sometimes they do, but often they don't.

Either way, when we look at such pictures (or even just think about them), our brains start to melt. A just-published study from Yale University shows that the average person's psychological IQ -- by which I mean not their overall intelligence, but rather their capacity to think straight about psychology -- drops about 20 points the minute they hear the words "frontal lobes". In the Yale study, three groups of subjects -- ordinary joes, undergrads taking a neuroscience course, and experts -- read brief discussions of psychological phenomena, and then had to say whether the explanations made sense or not.

To take a typical example, subjects might read about a phenomenon known as "the curse of knowledge" (something I discussed recently at klugetheblog.com). As the experimenters describe it, the curse of knowledge is about believing that if you know something, you expect that most other people will, too:

Researchers created a list of facts that about 50% of people knew. Subjects in this experiment read the list of facts and had to say which ones they knew. They then had to judge what percentage of other people would know those facts. ..... If the subjects did know a fact, they [presumed] that an inaccurately large percentage of others would know it, too. For example, if a subject already knew that Hartford was the capital of Connecticut, that subject might say that 80% of people would know this, even though the correct answer is 50%.

Why should that be the case? Subjects in the Yale experiment had to sift through explanations like these, deciding which were good explanations, and which were poor explanations:

1. The researchers claim that this '' curse '' happens because subjects have trouble switching their point of view to consider what someone else might know, mistakenly projecting their own knowledge onto others.

2. The researchers claim that this '' curse' happens because subjects make more mistakes when they have to judge the knowledge of others. People are much better at judging what they themselves know.

3. Brainscans indicate that this '' curse '' happens because of the frontallobe brain circuitry known to be involved in self-knowledge. Subjects have trouble switching their point of view to consider what someone else might know, mistakenly projecting their own knowledge onto others.

4. Brainscans indicate that this ''curse ''happens because of the frontal lobe brain circuitry known to be involved in self-knowledge. Subjects make more mistakes when they have to judge the knowledge of others. People are much better at judging what they themselves know.

Subjects in the Yale study were pretty good at distinguishing between #1 and #2. (#1 is a good explanation, since it tells us *why* the curse of knowledge might exit; #2 is empty.) But (except for the experts) people were terrible at distinguishing #3 from #4, and in fact  manythought that #4 (which in reality is no more illuminating than #2) was nearly as good as #1.

As the study's authors -- Deena Wiesberg and her colleagues -- put it ,"It is not the mere presence of verbiage about neuroscience that encourages people to think more favorably of an explanation. Rather, neuroscience information seems to have the specific effect of making bad explanations look significantly more satisfying than they would without neuroscience."

Why are we such suckers?

Gary Marcus is the author of the new book Kluge: The Haphazard Construction of the Human Mind, an in-depth look at the fallacies of human thought.

Comments

[Nutcase]

Actually, one of the biggest problems with fMRIs is the reaction of many of the professionals. It is a new toy. They love to play with their new toy. They see it as the latest, greatest miracle. Since they are so expensive, it is necessary to justify them by showing them to be cost-effective. This means they are finding many uses for them, from identifying the location of everything from manic-depression to various addictions to being a lie detector.

[Aaror]

Actually, they just did a study where they took brain scans of individuals learning about brain scan studies and individuals learning of other psycological datums, and the former group had a 15% drop in prefrontal activity, indicating conclusivly that I am good at making this crap up as I go along (grin).

[PioneerKing]

The answer is NO. Just ask George Bush, Sean Hannity, Rush Limbaugh and Bill O' to name a few. these folks have never had their brains scanned and are about as smart as a bucket spit.

[tbone99]

The latest bullshit imaging conclusion is hearing that ther's a gene for PTS syndrome.Even though they explain it can't work without enviromental activation , isn't it just another way to blame the victim.?Iit seems to me as a lot of this research is just the old chicken before the egg question asked with million dollar machines.

[Dap]

BTW

"But do they actually tell us anything? Sometimes they do, *but often they don't*."

What ya mean to say is in many cases we don't have enough understanding to fully interpret what is being witnessed. Remember when other animals were just dumb beasts?

[Dap]

Personally I was pondering this just last week after responding to a couple of post, strange. It also seems that I personal assume that others understand what I'm speaking to when addressing some complex subjects, alluding to that which I believe others (especially in a field of study) should be cognizant.

As far as this essay/post goes, I'm of the mind this "curse" was understood well before fMRI imagining, in the field of clinical psychology. What fMRI adds is subject to the knowledge of those conducting any such study, as it is with all scientific studies "Garbage in, garbage out." Let us face some hard facts, researchers are subject to all the frailties of the human condition as other human beings. biases, avarice, paying the bills, and other influences from outside sources, even plain ol' mistakes and time restraints.

It all gets pretty complex, and in today's world many times it comes down to ones trust in others abilities and integrity. The article speaks to frontal lobes, well that's *NOT* where memory resides, or should I say starts, what goes through the brain in a nanosecond is quite wondrous, how all the information makes it's way from short term memory into each individuals (dependent on ones interest) long term memory. Then ya move to recall, digging it back out from the neural-network.

Here's a strange one, personally my best and most profound problem solving has always come from processing during sleep, it has been that way since I was a child.

You keep up the good work, because it is of import, without question.

[OTOH]

#3 and #4 are non sequiturs, but a subject who is given no chance to ask for clarifications might reasonably assume that, since the study looks stupid anyway, someone was quoting scientific research badly and there must be something to the brainscans that are being quoted. In other words, the subject might assume that the explanations are not intentionally fuzzy -- they were just written by someone who didn't do a good job summarizing the research.

If I were given these four explanations I would want to ask more questions. Not given the chance to do so, if I had to bet one one of them I might bet on #3 or #4 not because they make sense to me but because they are obviously badly written but they hold the potential of containing an explanation -- whereas #1 and #2 are simply tautological.

[Herrington]

Sorry, you can't talk me out of encouraging science in public education ; )

It is not so easy to predict what others know, but is very easy to tell what they know if you are looking at a blank stare when you finish speaking.

And, nothing of any value whatever is demonstrated by this "experiment". Know your audience?

Well, not quite true, it is consistent with studies that have shown that the incompetent have trouble comprehending what competence is and therefore overrate their competency.

[anfractuous]

>It is not so easy to predict what others know, but is very easy to tell what they know if you are looking at a blank stare when you finish speaking.

More often, you get a lot of head nodding, which if prolonged, decays into a deep sleep. A complete absence of response to "Any questions?" is usually not a tribute to your abilities as a communicator.