Chemero (2009), Chapter 2: Embodied Cognition

Chemero spent Chapter 1 creating space for himself and his book in the marketplace of ideas about how we should do our cognitive science. Chapter 2 is about situating his theory in amongst the competition, with the goal of establishing exactly what a radical embodied cognitive science (RECS) is, and that it is a perfectly respectable competitor. He reviews a little history and an example study using dynamical systems that explains a  'representationally hungry' cognitive task to set things up. This is still quite preliminary work, but time well spent I think.

Chemero (2009), Chapter 1: Hegelian Arguments in Cognitive Science

The basic thesis of RECS is that cognitive science should give up on representations (the radical bit) and focus on explaining the embodiment of cognition in a complex, perceiving-acting dynamical system. Chemero spends Chapter 1 heading off the likely initial line of resistance to this thesis; namely, the argument that 'your thesis got ruled out in the 80s by [insert name here]'. Chemero labels arguments of this type 'Hegelian' and makes a case that a) they're mostly a sign of the immaturity of modern cognitive science, but most importantly b) they don't really need to convince anyone to stop trying to develop a radical, embodied cognitive science (and that the rest of the book is therefore still worth a read). I basically agree with this analysis; in fact, we started this blog to try and address the immaturity issue in (a) (in favour of some form of (b)). So we're off to a good start!

New Reading Group: Chemero (2009), Radical Embodied Cognitive Science

I thought it was time to pick up the next book I have on my list to go through here on the blog. This is Tony Chemero's book, Radical Embodied Cognitive Science (hence RECS). I've read through it once, and it inspired me to write on affordances here, here and here. My goal now is to take things a little more slowly and think about the detail.

Tony is a philosopher who's been actively engaged in things ecological for quite a while now. The goal of RECS is to lay out a) what radical embodied cognitive science is, b) propose a methodological stance in the form of dynamical systems, and then c) lay out how ecological psychology is the key theoretical structure that gives this approach it's methods for 'discovery', i.e. the ability to make predictions and do normal science. (Still curious? Check out the Wordle of the book!) Chemero's going to invoke what he describes as 'shored-up ecological psychology'; this refers to his ideas on the ontology of affordances and on information. I'm not currently all that convinced by the changes, but I'll leave the details until we get there. I'll try and entice Tony into stopping by, hopefully we can have a dialogue on some of this material (especially the later chapters on his 'shored up' version of Gibson).

I've been preparing posts on chapters for the last few months, actually, but I've waited to start posting so that I could be well ahead before I got going. This is going to let me tweak the posts with later information in mind, as well as post updates fairly regularly without crushing my schedule. I'm really enjoying this extended process, I'm coming to grips with what Tony is up to and it's been an excellent way to really study the book. My optimistic plan is to stay ahead like this, and move onto other books in the future.

I'll post on the first chapter as next Tuesday's update; I'd love it if people were reading along and commenting.

Reference

Chemero, A. (2009). Radical Embodied Cognitive Science. Cambridge, MA: MIT Press. Amazon.com, Amazon.co.uk, MIT Press e-book

F*cking affordances - how do they work?

Over on Bounds of Cognition, Ken has been doggedly pursuing what he thinks is a critical problem with the concept of affordances as described by Gibson (1979) and expanded on by Turvey, Shaw, Reed & Mace (1981; hence TSRM). I feel the need to spend some time consolidating my responses and some ideas in one place; every time I try to lay out why the problem is ill-posed or a potential route out, Ken just says I'm clouding or avoiding the issue or throwing out red herrings.

I actually think Ken has identified one very useful critique of the affordance concept: the lack of care with which we attach '-able' to words. But Ken isn't just making a methodological point; he thinks he's shown that affordances cannot structure light in a way that can specify the affordance, and that's the argument that needs to be tackled.

Saddle up: this is going to take some time, and I'm not going to solve everything. But to get a little ahead of myself, the answer to the problem is that it's complicated.

The Size-Weight Illusion is Functional, and It's About Throwing

My colleagues, Geoff Bingham and Qin Zhu, have recently published some fascinating data which has emerged from their work on the uniquely human skill, long-distance throwing. This is a novel and rich perception-action task which Bingham and Zhu (and recently, me) have been investigating for some time, with many interesting results. I'll get onto blogging about this project once I've caught up with the coordination studies and have had some time to get my head around the data I'm helping generate.

I wanted to blog about this new paper, though, because it's an exciting result which deserves all the attention it gets. The result is about the size-weight illusion, one of the most robust illusions around. As I've talked about before, illusions are a concern to ecological psychologists only in that they suggest the task has been incorrectly characterised. This paper presents data that suggests the size-weight illusion is actually functional, and that it reflects the readiness of the human perception-action system to throw objects long distances.

This paper has seen some activity in the popular press already (e.g. here and here): Geoff's hoping for the NYT Science section too! 

UPDATE: Geoff being interview on NPR

Identifying the Visual Information for Relative Phase

Bingham's model predicts that the information for relative phase is the relative direction of movement. The first direct test of this hypothesis was the experiment that followed on from my learning study, in which we systematically perturbed the various candidate information variables to see which affected performance in the perceptual judgement task.

I like this study a lot, if I do say so myself. It's a serious attempt to make a strong test of the model's predictions, and we invested a lot of time in the methodology. This is also that rare paper that benefited from a vigorous review process; the end result is, I think, a clear, careful, and detailed presentation of a critical result for the perception-action approach Geoff and I are developing.

Readers interested in the issue of how you can scientifically study information from an ecological perspective should certainly read the paper (Ken, that's you :); it's my go-to reference for how I believe this has to be done. The main lesson - it's hard to do this properly, but the rewards, in terms of unambiguous data, are clear.

Perceptual Learning Stabilises Action: A Test of the Bingham Model

Bingham's perception-action model was initially inspired by perceptual judgement studies (using vision and proprioception). The HKB phenomena are movement phenomena, however; simply noting that the same qualitative pattern is seen in different judgement and action studies is a good first step but only suggestive, at best. We therefore next took simultaneous judgement & action measures from a movement task where we manipulated the feedback display (Wilson et al, 2005a). For instance, when the display showed 0°, movement was stable, even when the movement was at, for example, 90°. Perception of relative phase was driving the stability of the movements.

On the basis of all this data, the model predicts that the reason 0° and 180° are easy is that the information specifying that you are moving this way is easily perceived. There is provisional evidence to support relative direction of motion as the specifying information (Bogaerts et al, 2003; Wilson et al, 2005b; Wimmers et al, 1992) with relative speed acting as a noise term. This variable certainly predicts the observed pattern, as the relative direction of motion is only stable at 0° and 180°. It is maximally variable at 90°, which would explain why movements here are also maximally unstable. The model is therefore explaining the problem with moving at 90° as a problem detecting the information required to maintain the coordination; as we saw in the case of friction, no information means unstable behaviour.

The model therefore makes a critical prediction. If we could improve people's ability to perceive 90°, they should gain the ability to move at 90° without any practice at the movement itself. All previous learning studies had entailed training people to move by having them move, with the help of various forms of transformed feedback methods (visual metronomes or Lissajous plots; more on this when I discuss feedback). The prediction, that movement stability should improve with improved perceptual ability, is a strong test of both the model and the modelling strategy in general, and the experiment to test it was the first half of my dissertation.