Some good stuff about reading in a new book by Mark Seidenberg, a cognitive neuroscientist heavily influenced by computational models of reading. The book’s full title is: Language At The Speed Of Sight: How We Read, Why So Many Can’t, And What Can Be Done About It, and of particular interest is chapter 4, “The Eyes Have It”. Here are some key concepts:
- The properties of the visual system imposes limits and constraints on reading.
- Eye movements involve two decisions: where to look and when to move.
- Properties of the perceptual span are linked to the neurobiology of the retina.
- Information outside the fovea is useful even though it is imprecise.
- Magnifying letters in the periphery is ineffective because we’re already wrapping chocolates as fast as we can.
- If you try to read real texts at peak words-per-minute rate, you’ll blow your engine pretty fast.
As much delectable food for thought as there is in the book, I wish Seideberg had gone deeper and further into several areas:
- There is limited discussion about the interface between eyes and brain. Of course we know that reading takes place in the brain rather than the eyes. But the eyes aren’t merely a bottleneck to be treated as a nuisance.
- The graphophonic concept bears deeper discussion in terms of the visual system and how phonemes and graphemes map and correspond to one another. Seidenberg hints at this in terms of the role of the occipito-temporal cortex as nature’s contrivance to orthography.
- There is nary a single word in the chapter about binocular vision. As with the reading field at large, he deals with the visual reading process entirely from a cyclopean point of view.
Nor is this surprising. Seidenberg was heavily influenced by the late Keith Rayner. The most influential researcher on eye movements and reading in the 20th century, Rayner adopted the cyclopean point of view, essentially treating the binocular system as an epiphenomenon. Which brings a story to mind. About 15 years ago, Dr. Gary Williams invited Keith Rayner to present a lecture to the annual COVD meeting. Gary, Ken Ciuffreda, and I took Keith to dinner, and I struck up a conversation with him about binocular vision and reading. I asked him if he thought that an individual with convergence insufficiency, who perceived print to be unstable our doubling intermittently, might have their eye movements while reading impacted by the condition. He looked at me quizzically and asked, in all sincerity: “Are there really individuals who experience that?”