Image from Prefrontal.org: The Story Behind the Atlantic Salmon

Unfortunate news for “evolutionary psychologists” who use fMRI brain scans to “prove” things about people’s gendered neural wiring. Here’s a link to a cool poster from Craig Bennett, Abigail Baird, Michael Miller, and George Wolford, using real science and real fMRI brain scans, that “demonstrates” how different areas of a brain “light up” when the subject is asked to categorize the facial expressions of people in photographs. The brain they used was an atlantic salmon brain. A dead atlantic salmon brain!

From the introduction:

With the extreme dimensionality of functional neuroimaging data comes extreme risk for false positives. Across the 130,000 voxels in a typical fMRI volume the probability of a false positive is almost certain. ... To illustrate the magnitude of the problem we carried out a real experiment that demonstrates the danger of not correcting for chance properly.

From the discussion

Can we conclude from this data that the [dead!] salmon is engaging in the perspective-taking task? Certainly not.

Again, as always, not to say one can’t do brain research with fMRI technology. Just that it’s going to take more work than the average “evolutionary psychologist” (who, remember, may not have taken a biology class since high-school!!!) is going to have the funding, or the technical background, to use fMRI techniques to conclusively prove that, say, brain-reward circuits “exhibit a linear increase in activation with increased judgments of attractiveness.”

Again, not to say it can’t be done (it almost certainly can, now or in the not too distant future.) Or is it to say that it couldn’t be true. Just that you probably need to be able to demonstrate that the same results couldn’t be derived from a dead fish brain before we take your “conclusions” very seriously.

And yes, I did use an awful lot of scare quotes in this post.

(Via Mark Liberman. Complete discussion in a blog post from the author, Craig Bennett, here.)