Another article on the limits of neuroscience has appeared in a high-profile media outlet aimed at a general audience. In The New Yorker, NYU Psychology Professor Gary Marcus writes about What Neuroscience Really Teaches Us, and What It Doesn't. As usual, the focus is on the seductive allure of colorized brain images:
Neuroscience Fiction
Posted by Gary Marcus
December 2, 2012
...Brain imaging, which was scarcely on the public’s radar in 1990, became the most prestigious way of understanding human mental life. The prefix “neuro” showed up everywhere: neurolaw, neuroeconomics, neuropolitics. Neuroethicists wondered about whether you could alter someone’s prison sentence based on the size of their neocortex.
And then, boom! After two decades of almost complete dominance, a few bright souls started speaking up, asking: Are all these brain studies really telling us much as we think they are? A terrific but unheralded book published last year, “Neuromania,” worried about our growing obsession with brain imaging. A second book, by Raymond Tallis, published this year, invoked the same term and made similar arguments. In the book “Out of our Heads,” the philosopher Alva Noë wrote, ”It is easy to overlook the fact that images… made by fMRI and PET are not actually pictures of the brain in action.” Instead, brain images are elaborate reconstructions that depend on complex mathematical assumptions that can, as one study earlier this year showed, sometimes yield slightly different results when analyzed on different types of computers.
Last week, worries like these, and those of thoughtful blogs like Neuroskeptic and The Neurocritic, finally hit the mainstream, in the form of a blunt New York Times op-ed, in which the journalist Alissa Quart declared, “I applaud the backlash against what is sometimes called brain porn, which raises important questions about this reductionist, sloppy thinking and our willingness to accept seemingly neuroscientific explanations for, well, nearly everything.”
I wrote about Quart's op-ed piece in Meet The Neuro Doubters, where I tried to strike a balance between justified criticism of flawed studies and bad press releases versus trendy overhyped trashing of 'neurobollocks' and neuroscience research in general. Professor Marcus tries to maintain this distinction as well:
Quart and the growing chorus of neuro-critics are half right: our early-twenty-first-century world truly is filled with brain porn, with sloppy reductionist thinking and an unseemly lust for neuroscientific explanations. But the right solution is not to abandon neuroscience altogether, it’s to better understand what neuroscience can and cannot tell us, and why.
The first and foremost reason why we shouldn’t simply disown neuroscience altogether is an obvious one: if we want to understand our minds, from which all of human nature springs, we must come to grips with the brain’s biology. The second is that neuroscience has already told us lot, just not the sort of things we may think it has.
Judging from reaction on social media, the position of abandoning neuroscience can be seen as a straw man, but Raymond Tallis takes his neurotrash rather seriously; so do many liberal intellectual media outlets. The danger of professional neurocriticism is that it will be used by the anti-science crowd to discredit a reductionist enterprise.
What have we learned?
In the wake of the 2009 voodoo correlations brouhaha (Vul et al., 2009), which caused some to dismiss all neuroimaging as garbage, I stated that...
...I am not a complete neuroimaging nihilist. For examples of this view, see Coltheart, 2006 and especially van Orden and Paap, 1997 (as quoted by Coltheart):What has functional neuroimaging told us about the mind so far? Nothing, and it never will: the nature of cognition is such that this technique in principle cannot provide evidence about the nature of cognition.So no, I am not a Jerry Fodor Functionalist. I do believe that learning about human brain function is essential to learing about "the mind," that the latter can be reduced to the former, that fMRI can have something useful to say, and (more broadly, in case any anti-psychiatry types are listening) that psychiatric disorders are indeed caused by faulty brain function. But there's still a lot about fMRI as a technique that we don't really know. The best-practice statistical procedures for analyzing functional images is obviously a contentious issue; there is no consensus at this point. Our knowledge of what the BOLD signal is measuring, exactly, is not very clear either [see the recent announcement in J. Neurosci. that "BOLD Signals Do Not Always Reflect Neural Activity."] The critics among us are not trying to trash the entire field of social neuroscience (or neuroimaging in general). Some of us are taking concrete steps to open a dialogue and improve its methodology, while others are trying to rein in runaway interpretations.
And really, cognitive neuroscience is not the only guilty party here. All sorts of scientific findings are overhyped by the media, university press releases, even scientists themselves. Why do scientists do this? Because it's very difficult to get funding these days, and positioning one's basic research in mice as leading to an imminent cure for schizophrenia or autism is de rigueur. Then when it doesn't happen the public becomes disillusioned with science and politicians lobby for cuts in research funding.
I'll leave you with this cordial Twitter debate that concisely summarizes the problem.
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