The brain does linguistic hierarchy

I hope to blog on this paper by Poeppel and friends (the authors are Ding, Melloni, Zhang, Tian and Poeppel) more in the near future. However, for now, I wanted to bring it to your attention. This is an important addition to the growing number of papers that are beginning to use linguistic notions seriously to map brain behavior. There have been earlier papers by Dehaene and Friederici and Frankland and Greene and, no doubt others. But it looks to me that the number of these kinds of papers is increasing, and I take this to be a very good thing. Let's hope it soon puts to sleep the idea,s till prevalent among influential people, that hierarchy is tough or unnatural for brains to do, despite the overwhelming behavioral evidence that brains/minds indeed do it (see here for a monumentally dumb paper).

One warning: some of the hype around the Poeppel & Co paper are reporting it as final vindication of Chomsky's views (see here). From a linguists point of view, it is rather the reverse: this is a vindication of the idea that standard neuro methods can be of utility in investigating human cog-neuro capacities. In fact, the title of the Poeppel & Co paper indicates that this is how they are thinking of it as well. However, the hype does in fact respond to a standing prejudice in the brain sciences and so advertising the results in this way makes some rhetorical sense. As the Medical Press release accurately notes:

Neuroscientists and psychologists predominantly reject this viewpoint, contending that our comprehension does not result from an internal grammar; rather, it is based on both statistical calculations between words and sound cues to structure. That is, we know from experience how sentences should be properly constructed—a reservoir of information we employ upon hearing words and phrases. Many linguists, in contrast, argue that hierarchical structure building is a central feature of language processing.

And given this background, a little corrective hype might be forgivable. By the way, it is important to understand that the result is linguistically modest. It shows that hierarchical dependencies is something the brain tracks and that stats cannot be the explanation for the results discovered. It does not tell us what specific hierarchical structures are being observed and which linguistic structures the might point to. That said, take a look. the paper is sure to be important.