Field of Science

Video games, rotted brains, and book reviews

Jonah Lehrer has an extended discussion of his review of The Shallows, a new book claiming that the Internet is bad for our brains. Lehrer is skeptical, pointing out that worries about new technology are as old as time (Socrates thought books would make people stupid, too). I am skeptical as well, but I'm also skeptical of (parts of) Lehrer's arguments. The crux of the argument is as follows:
I think it's far too soon to be drawing firm conclusions about the negative effects of the web. Furthermore, as I note in the review, the majority of experiments that have looked directly at the effects of the internet, video games and online social networking have actually found significant cognitive benefits.
That, so far as it goes, is reasonable. My objection is to some of the evidence given:
A 2009 study by neuroscientists at the University of California, Los Angeles, found that performing Google searches led to increased activity in the dorsolateral prefrontal cortex, at least when compared with reading a "book-like text." Interestingly, this brain area underlies the precise talents, like selective attention and deliberate analysis, that Carr says have vanished in the age of the Internet. Google, in other words, isn't making us stupid -- it's exercising the very mental muscles that make us smarter.
This cuts several ways. Extra activation of a region in an fMRI experiment is interpreted different ways by different researchers. It could be evidence of extra specialization ... or evidence that the brain network in question is damaged and so needs to work extra hard. Lehrer is at least partially aware of this problem:
Now these studies are all imperfect and provisional. (For one thing, it's not easy to play with Google while lying still in a brain scanner.)
This is the line I have a particular issue with. If the question is whether extra Internet use makes people stupid, why on Earth would anyone need to use a $600/hr MRI machine to answer that question? We have loads of cheap psychometric tests of cognition. All methodologies have their place, and a behavior question is most easily answered with behavioral methods. MRI is far more limited.

Lehrer's discussion of the 2009 study above underscores this point: the interpretation of the brain images rests on our understanding of what behaviors the dorsolateral prefrontal cortex has shown up with in other studies. The logic is: A correlates with B correlates with C, thus A correlates with C. This is, as any logician will tell you, an unsound conclusion. When you add that using MRI can cost ten thousand dollars for a single experiment, it's a very expensive middleman!

Which isn't to say that MRI is useless or such studies are a waste of time. MRI is particularly helpful in understanding how the brain gives rise to various types of behavior, and it's sometimes helpful for analyzing behavior that we can't directly see. Neither applies here. If the Internet makes us dumb in a way only detectable with super-modern equipment, I think we can breath easy and ignore the problem. What we care about is whether people in fact are more easily distracted, have worse memory, etc. That doesn't require any special technology -- even Socrates could run that experiment.

Lehrer does discuss a number of good behavioral experiments. Despite my peevishness over the "Google in the scanner" line, the review is more than worth reading.

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