Saturday, November 28, 2009

Long hiatus, a great book, and skiing in the forecast

I've been so busy with work and travel that I've not had the time and focus for writing. We have been in Philadelphia for a family Thanksgiving. At the Penn Book Center a week ago, I came upon Stanislas Dehaene's Reading in the Brain. I'm only 100 pages in, but it has already taken top rank in my mental gallery of science books. It's a deep, serious work about brain architecture, perception, and cognition, but written without any pretense or pomp, direct, full of striking news about how reading is implemented in the brain. In these first chapters, Dehaene focuses on what is known about reading's implementation and on the experimental evidence for the findings. I'm looking forward for when he gets into how the design of writing systems is influenced by biological constraints, and how reading gets localized to the same particular brain region, which he calls the “letterbox,” across languages, writing systems, and cultures (He's already given a tantalizing preview regarding the localization of Kanji and Kana in Japanese reading).

My new skis, Black Diamond Justices with Marker Baron bindings, are waiting for me at Marmot Mountain Works in Berkeley. I'm not likely to be able to use them the coming weekend because I signed up for an ASI wilderness first aid class at Sugar Bowl, but I'll be in Whistler the following weekend, where they have been having the best early season in a long time. Now I just need the jet stream to behave to keep both pineapple express and deep freeze away.


Simon Spero said...

I saw a brief review of Reading in the Brain from the New Scientist. The book looks interesting, but the article below made me a little sceptical. I still want to read it, though I'm worried that half way through I'll start thinking about how hard reading is, and discover that I can't.


Price, Cathy J, and Joseph T. Devlin (2003). "The myth of the visual word form area". NeuroImage 19:473-481. doi:


Recent functional imaging studies have referred to a posterior region of the left midfusiform gyrus as the “visual word form area”
(VWFA). We review the evidence for this claim and argue that neither the neuropsychological nor neuroimaging data are consistent with
a cortical region specialized for visual word form representations. Specifically, there are no reported cases of pure alexia who have deficits
limited to visual word form processing and damage limited to the left midfusiform. In addition, we present functional imaging data to
demonstrate that the so-called VWFA is activated by normal subjects during tasks that do not engage visual word form processing such as
naming colors, naming pictures, reading Braille, repeating auditory words, and making manual action responses to pictures of meaningless
objects. If the midfusiform region has a single function that underlies all these tasks, then it does not correspond to visual word form
processing. On the other hand, if the region participates in several functions as defined by its interactions with other cortical areas, then
identifying the neural system sustaining visual word form representations requires identification of the set of regions involved. We conclude
that there is no evidence that visual word form representations are subtended by a single patch of neuronal cortex and it is misleading to
label the left midfusiform region as the visual word form area.

Fernando Pereira said...

@Simon: Deheane's main hypothesis is not simply that there is a VWFA, but that certain areas, in particular in the lower-left occipital cortex but not only there, appear to be preferentially recruited for reading. His argument is complex and gives good play to contrary evidence and uncertainty. I've read another 100 pages, and if anything the book gets more impressive.

Simon Spero said...

You convinced me to track down a copy; I haven't had time to do more than skim a few pages, but it looks like a good read. I definitely saw some greebles, so I'm hoping for a FFA/VWFA comparison.

There is a citation to Price and Devlin in n.53 (p62) [it's not in the index, because the indexer didn't do the end-notes]. That note points to the reply by Cohen and Dehaene:
Cohen L. and Dehaene S. (2004), Specialization within the ventral stream: the case for the visual word form area. NeuroImage 22:466-476 DOI: 10.1016/j.neuroimage.2003.12.049.