How big is the present? Classic theories of perception all essentially assume that 'now' is some instantaneous slice of time, and that the task of perception is to reconstruct the flow of experience from the snapshots provided by, for example, the eye. But phenomenologically, our experience clearly occurs over time, and it is not clear how you can reinsert time into a perceptual system that detects static slices (in the same way it is not clear how you can uniquely recover the third spatial dimension from a 2D retinal image). In other words, perceptual experience is 4 dimensional - three spatial and one temporal - and we are supposedly creating this from a series of two (spatial) dimensional snapshots.
It's been a good day for this sort of thing; shortly after my last post I came across this blog post via Gizmodo. It describes the curious case of Neil, who cannot see colour but who has learned to hear it, via a camera that encodes colours as sounds.
NPR has a cute little animation (via BoingBoing) about the story of writer Howard Engel. Engel suffered a minor stroke which left him unable to read words, but he could still write (and read what he wrote for a short period, before it faded into incomprehensibility).
Fascinatingly, he has taught himself to read again using touch. By tracing a letter with his finger (or eventually with his tongue on the roof of his mouth or back of his teeth) he could identify it; he's fast enough now with his tongue that he can read about half of the subtitles in a foreign movie!
So far, Gibson has explained how invariant structure can emerge from changes in perspective (see here and here). How he gets down to the real problem. What are the consequences of this structure for the ambient optic array. What is it that I see, as a perceiver, that specifies things about the environment?
I'm just back from the 11th European Workshop on Ecological Psychology and I have a few posts about things that arose there. Ecological psychology is, reassuringly, in better empirical form than I had been thinking; there are still people doing things badly, but plenty going after things as carefully as they should be, with due attention to issues of information. So that was good.
There was one talk by John Wann on the neural control of steering in driving tasks. I like John a lot, and respect his work - he's a very careful experimentalist and not at all susceptible to fads in psychology, and his work has always included detailed use of perceptual information in sensible ways. He has recently been involved in some fMRI versions of his steering studies with a post-doc trained in imaging, and he presented this data to the conference.
I left this part of Chapter 4 as a separate post because the end discusses a problem, the problem of two minds, in some detail and it made sense to split it out. This section ties Gibson to James again by highlighting how his ecological optics can solve a problem within radical empiricism, demonstrating that they are, indeed, connected in interesting ways. This will also segue a little back into dispositions, although only briefly; I've been doing some digging and, as I suspected, the philosophical discussion of what dispositions are has moved on since Turvey (1992). Over the next little while I'll be attempting to read some of the philosophy literature, with the help of a philosopher friend of mine, with the goal of producing some papers for the philosophical and eco-psych communities.