Colin Klein

Consciousness supervenes on activity; computation supervenes on structure. Because of this, some argue, conscious states cannot supervene on computational ones. If true, this would present serious difficulties for computationalist analyses of consciousness (or, indeed, of any domain with properties that supervene on actual activity). I argue that the computationalist can avoid the Superfluous Structure Problem (SSP) by moving to a dispositional theory of implementation. On a dispositional theory, the activity of computation depends entirely on changes in the intrinsic properties of implementing material. As extraneous structure is not required for computation, a system can implement a program running on some but not all possible inputs. Dispositional computationalism thus permits episodes of computational activity that correspond to potential episodes of conscious awareness. The SSP cannot be motivated against this account, and so computationalism may be preserved

Some vegetative state patients show fMRI responses similar to those of healthy controls when instructed to perform mental imagery tasks. Many authors have argued that this provides evidence that such patients are in fact conscious, as response to commands requires intentional agency. I argue for an alternative reading, on which responsive patients have a deficit similar to that seen in severe forms of akinetic mutism. Akinetic mutism is marked by the inability to form and maintain intentions to act. Responsive patients are likely still conscious. However, the route to this conclusion does not support attributions of intentional agency. I argue that aspects of consciousness, rather than broad diagnostic categories, are the more appropriate target of empirical investigation. Investigating aspects of consciousness provides a better method for investigating profound disorders of consciousness. 1 Introduction2 Responses in the Vegetative State2.1 The imaging evidence2.2 The need for models3 Responsive Patients and Akinetic Mutism3.1 Akinetic mutism3.2 Akinetic mutism as a deficit in intentions3.3 Arguments for the link3.4 Interim conclusion4 Other Models4.1 A deficit in ability?4.2 Modular intentions?5 Consciousness and Method5.1 Are they conscious?5.2 Aspects versus levels.

Contrastive neuroimaging is often taken to provide evidence about the localization of cognitive functions. After canvassing some problems with this approach, I offer an alternative: neuroimaging gives evidence about regions of the brain that bear difference-making relationships to psychological processes of interest. I distinguish between the specificity and what I call the systematicity of a difference-making relationship, and I show how at least some neuroimaging experiments can give evidence for systematic difference-making.

In a target article that appeared in this journal, Thomas Stoffregen 2000 questions the possibility of ecological event perception research. This paper describes an experiments performed to examine the perception of the disappearance of gap-crossing affordances, a variety of event as defined by Chemero 2000. We found that subjects reliably perceive both gap-crossing affordances and the disappearance of gap-crossing affordances. Our findings provide empirical evidence in favor of understanding events as changes in the layout of affordances, shoring up event perception research in ecological psychology.

Multiply realizable kinds are scientifically problematic, for it appears that we should not expect discoveries about them to hold of other members of that kind. As such, it looks like MR kinds should have no place in the ontology of the special sciences. Many resist this conclusion, however, because we lack a positive account of the role that certain realization-unrestricted terms play in special science explanations. I argue that many such terms actually pick out idealizing models. Idealizing explanation has many of the features normally associated with explanation by MR kinds. As idealized models are usually mere possibilia, such explanations do not run afoul of the metaphysical problems that plague MR kinds.