Pinker vs. Greenfield: is facebook rotting your brain?

I read two articles in the last week by leading intellectuals about what effect mass media have on the brain. One of them was Steven Pinker: Mind Over Mass Media. Pinker's conclusion:

The new media have caught on for a reason. Knowledge is increasing exponentially; human brainpower and waking hours are not. Fortunately, the Internet and information technologies are helping us manage, search and retrieve our collective intellectual output at different scales, from Twitter and previews to e-books and online encyclopedias. Far from making us stupid, these technologies are the only things that will keep us smart.

In a fairly scholarly article for Edge, Pinker cites evidence from cognitive science, psychology and neuroscience. He explains the bias that causes people to believe that mass media is damaging our brains:

As with primitive peoples who believe that eating fierce animals will make them fierce, they assume that watching quick cuts in rock videos turns your mental life into quick cuts or that reading bullet points and Twitter postings turns your thoughts into bullet points and Twitter postings

He pithily ridicules the notion that "changing our brains" is a bad thing:

Yes, every time we learn a fact or skill the wiring of the brain changes; it's not as if the information is stored in the pancreas

The other article I read was an interview with Baroness Greenfield, with the headline Facebook Addicts Can't Relate, Greenfield is worried about the effect social media is having on a generation that is growing up with it as a regular means of communication:

If you are not rehearsing looking someone in the eye in three dimensions, but instead you have 900 friends on Facebook ... one does question what kind of relationship they might be having,

In defence of her position that facebook might be contributing to rising levels of ADD (how can a diagnosis that didn't exist 30 years ago be rising?) she cites... erm... some studies that haven't actually been done:

Perhaps it's mandating a shorter attention span. I'm not saying it is but I'm saying, 'Wouldn't it be worth exploring?'

Of course it would be worth exploring.. but what is the point in encouraging sensationalist and uninformed scare stories in the press until it has been explored? She also warns us (somewhat ungrammatically) to be careful before we ignore her non-argument:

We are being complacent in the extreme if you just dismiss me as a whingeing, middle-aged Luddite.

Indeed... I'm not quite sure on what planet 59 qualifies as 'middle-aged' (the average age is still less than 80). But she's right, it would be silly to dismiss her fears because of her age, or her lack of fluency with the relevant technology. Dismissing them because they have absolutely no evidence to support them on the other hand...

I'll let you draw your own conclusions on which of the two articles I was most impressed by.