Similar philosophies

From A conversation about the brain
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Most of the ideas explored in these pages are 'old hat' in one way or another and most of the original sources are not (yet) referenced here. A target article by O'Regan and Noë (2001)[1] is a good place to start the discussion of a related framework for thinking about vision. O&N's article contained many ideas that are similar to those explored in these pages and it stimulated a lively debate.

There were, however, some points where O&N's ideas appear to differ from those explored in these pages. One issue concerns the reliance of the brain on the world as an 'outside memory' and the importance of the world as a necessary 'partner' in 'dance' (p966). When pushed into a corner over this, O&N insist that 'contemplative seeing' is possible (without movement) and even visual imagery in dreams but that these rely on the brain storing sensori-motor contingencies. In these pages, the issue of virtual movement has been flagged as one that appears to causes some tricky problems for the ideas explored here but O&N do not seem to admit this or provide any ingenious solution to the problem. It would seem that they cannot have it both ways. They can make a big fanfare about the world acting as an outside memory, with all the reductions in computation that that entails, but they must then be more explicit about what happens in the cases where the world is removed from the equation.

O&N appear to get in a slight tangle about the word 'representation'. Often they mean something like a Cartesian reconstruction of the world. But a store of sensori-motor contingencies is a representation, albeit of a different sort and at times O&N admit this. In the ideas set out in these pages, $\mathbf{W}$ is a representation of sensory+motivational contexts and contigencies.

Finally, O&N say some peculiar-sounding things about neural activity: "There can therefore be no one-to-one correspondence between visual experience and neural activations. Seeing is not constituted by activation of neural representations. Exactly the same neural state can underlie different experiences, just as the same body position can be part of different dances." (p966) Taken at face value, this is hard to square with the view O&N express about visual imagery, where the world in not involved and so the only thing changing is neural activation. Even for an observer interacting with the world, the only important thing changing, as far as explaining perception goes, is neural activation. It all seems a bit mysterious, not to say mystical.

Nevertheless, O&N's emphasis on interaction with the world, and in the case of visual imagery, a sequence of sensori-motor contingencies that have been previously learned in the world, is very close to the ideas discussed here about a sensory+motivational context, $\vec{c}, moving along paths through senosry+motivational space and, in general, theere is a considerable overlap between their hypothesis and the one set out in these pages.

References

  1. O'Regan, J. K., & Noë, A. (2001). A sensorimotor account of vision and visual consciousness. Behavioral and Brain Sciences, 24(05), 939-973.