I’m working on doing a clean literature review that will serve as a base for my second year project. I wrote a paper called “Where The Body Ends” last fall trying to pull together an argument that in some cognitive activities–like tool use–we should consider physical objects legitimate body parts, just like a finger or a callus.
I thought I did a good job in the paper of looking for support in a variety of fields, from anthropology to biology, but in the end my argument from a cognitive science perspective was quite weak. Thus I’m going back to the basics here, trimming away the fat and starting anew, trying to build a base of literature with only hard cognitive science evidence.
A writeup of what I have so far is below the fold. All of the works cited need to be revisited so I can expand my discussion. This is just a state-of-the-research writeup.
Introduction
While there are some who are unconvinced that the cognitive system extends beyond the nervous system, this research takes the distribution cognition theory for granted. It is taken as a given that bodies and artifacts play a role in cognition, the subject of inquiry are the similarities and differences between the many roles of bodies and artifacts.
There are three possibilities:
1) artifact plays, in the context of the cognitive system, a role functionally similar to body parts
2) artifact is an extension of the body, modifying representations and body programs
3) artifact is separate from the body
It is my hypothesis that the (1) exists. What leaves to be seen is how common it is, and what the circumstances are under which it exists.
Previous Work
Berti and Frassinetti (2000) describe a stroke victim “P.P.” who showed visual neglect while performing a bisection task in “near space” but not while performing the same task in “far space” with a laser pointer. However, when using a stick to perform the bisection task in far space, the neglect reappears. They use this result to support their hypothesis that tool use can affect visual perception. However, it also lends support for the idea that with respect to the bisection activity, the role of the stick is more similar to the role of the hand than the role of the laser pointer.
Berlucci and Agliotti (1998, p.561) claim that the body schema can be extended to include “non-corporeal objects that bear a systematic relation to the body itself”.
Maravita and Iriki (2004) present evidence of neural changes “compatible with the notion of the inclusion of tools in the ‘Body Schema’. Their evidence comes from single-cell recordings of monkeys using tools, and from experiments with normal and brain-damaged human.s
According to the theory of sensorimotor contingency, put forth by O’Reagan and Noe (2001), the senses are not differentiated based on the nature of their different neural pathways, but by the different patterns of sensorimotor contingencies created by the relationship between the particular perceptural machinery and the set of motor activities which they relate to. They cite the tactile vision substitution systems described by Bach-y-Rita (1996) as an example. In Bach-y-Rita’s experiment, blind participants were fitted with grids tiny vibrating rods, which could be used to “display” an image on the skin. After being allowed to move around in an environment, participants were able to perceive the locations of objects in 3D space. Rather than “feeling” the positions on their skin, participants reported feeling them in 3D space, suggesting that TVSS’s are able to create a kind of “vision via touch”. Clearly in this case, the TVSS is playing a role analagous to that of the optical system. I can think of no sound reason for considering the electronic part of the TVSS as environment while the flesh part remains body.
References
Bach-y-Rita, P. (1996) Sustitucion sensorielle et qualia. Reprinted (English translation) in Vision and Mind: Selected Readings in the Philosophy of Perception (Noë, A. and Thompson, E., eds), pp. 497–514, MIT Press
Giovanni Berlucchia, Salvatore Agliotia (1998) The body in the brain: neural bases of corporeal awareness. Trends in Neurosciences. Volume 20, Issue 12, 1 December 1997, Pages 560-564
http://dx.doi.org/10.1016/S0166-2236(97)01136-3
Anna Berti and Francesca Frassinetti (2000) When Far Becomes Near: Remapping of Space by Tool Use. Journal of Cognitive Neuroscience. 2000;12:415-420.
http://jocn.mitpress.org/cgi/content/full/12/3/415
Angelo Maravita, Atsushi Iriki (2004) Tools for the body (schema). TRENDS in Cognitive Sciences Vol.8 No.2 p.79-86 February 2004
O’Regan, J.K. & Noe, A. (2001). A sensorimotor account of vision and visual consciousness. Behavioral and Brain Sciences 24: 939-1031.