Over the past decade, many findings in cognitive about the contents of consciousness: we will not address neuroscience have resulted in the view that selective what might be called the ‘enabling factors’ for conscious- attention, working memory and cognitive control ness (e.g. appropriate neuromodulation from the brain- stem, etc.). involve competition between widely distributed rep-.

We share with Anderson & Lebiere (A&L) (and with Newell before them) the goal of developing a domain-general framework for modeling cognition, and we take seriously the issue of evaluation criteria. We advocate a more focused approach than the one reflected in Newell's criteria, based on analysis of failures as well as successes of models brought into close contact with experimental data. A&L attribute the shortcomings of our parallel-distributed processing framework to a failure to acknowledge a symbolic level of thought. (...) Our framework does acknowledge a symbolic level, contrary to their claim. What we deny is that the symbolic level is the level at which the principles of cognitive processing should be formulated. Models cast at a symbolic level are sometimes useful as high-level approximations of the underlying mechanisms of thought. The adequacy of this approximation will continue to increase as symbolic modelers continue to incorporate principles of parallel distributed processing. (shrink)

Humans display more conditioned fear when the conditioned stimulus in a fear conditioning paradigm is a picture of an individual from another race than when it is a picture of an individual from their own race (Olsson, Ebert, Banaji, & Phelps, 2005). These results have been interpreted in terms of a genetic “preparedness” to learn to fear individuals from different social groups (Ohman, 2005; Olsson et al., 2005). However, the associability of conditioned stimuli is strongly influenced by prior exposure to (...) those or similar stimuli. Using the Kalman filter, a normative statistical model, this article shows that superior fear conditioning to individuals from other groups is precisely what one would expect if participants perform optimal, Bayesian inference that takes their prior exposures to the different groups into account. There is therefore no need to postulate a genetic preparedness to learn to fear individuals from other races or social groups. (shrink)