I’ve been working a little more on my 2nd year project proposal while I’m traveling. Ed gave me some really good feedback about my introduction that I started to try to incorporate. It’s still so raw, but I’ll keep posting what I’m working on. It makes me feel more accountable for continuing to work on it, bit by bit. The new introduction is below the fold.
It has long been thought that in order to act we require an internal representation of our own bodies: a body schema. There is some evidence that neonates already have some kind of representation of their bodies, and it stands to reason that in order to survive the physical maturation process, significant changes in the body schema would be necessary. However, recent evidence suggests the plasticity of the body schema goes well beyond accommodations for the biological maturation process. Berti and Frassinetti (2000) show that the dissociation between near space and far space–traditionally thought of as a fixed property of the body schema–is affected by wielding tools. Maravita and Iriki (2004) showed that neurons previously responding only to a primate’s hand will begin to respond to a rake after a period of use
In addition to motor representions, the traditional domain of body schema, there is evidence for plasticity on the perceptive end of the embodiment equation. Bach-y-Rita (1996) shows that individuals augmented with a tactile-visual substitution system (TVSS), which maps a visual image to a somatosensory stimulation device quickly begin to perceive objects out in front of them, rather than on the surface of their skin. And Yamamoto and Kitazawa (2001) present evidence that when wielding a stick, textures are “felt” at the end of the stick, rather than at the interface with the hand.
This evidence seems to support two conclusions: 1) The body schema is quite plastic, supporting not just tweaks for maturation, but radical restructuring. 2) Changes in the body schema seem not to represent the structure of the flesh-and-blood body, but new sensorimotor contingencies, incorporating properties of tools. And this makes sense. How would a young nervous system “see” its body, except through monitoring the sensorimotor contingencies?
Clark (2007), suggests that the new results regarding the plasticity of the body schema suggest a unique kind of embodiment. Unlike a simple robot using a tool in a prescribed way, human beings are “profoundly embodied” agents, according to Clark, who “are biologically disposed towards literal (and repeated) episodes of sensory re-calibration, of bodily reconfiguration and of mental extension.” (p.263) We should not fear the possibility of ours becoming a race of cyborgs, he says, because we already are, and always have been.
These new insights should be particularly exciting to researchers studying human-computer interaction. HCI has long suffered a lackluster theoretical foundation both in academia and in industry, instead relying mostly on moderately effective but poorly understood methodologies and heuristics for designing digital systems. Theories of Psychology, and more recently Cognitive Science, have had limited success in explaining the “H” in HCI, and theories of computation and of external cognition have provided insight into the “C”. Rich theories–theories which are predictive, prescriptive and generative–of the actual interaction between the human and the machine have not yet materialized. [cite Rogers?] This “last mile” gap between the machine and the human may be one of the reasons that theories of HCI have seen such little uptake.
Excitingly, the theory of “profound embodiment” may be among the first theories to really bridge that gap. The notion of a highly plastic body schema can begin to explain how digital tools are represented in the brain. It may explain what is happening at a low level, when we encounter a new digital device and start to “feel it out”. And it may provide a framework for explaining what happens when the interaction breaks down.
There’s a little more in the actual proposal at the end where I lay out my long-term research goal and lay out different ways of attacking it, but it’s not quite ready for prime time.