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Blindsight – the ability that some people with striate cortical lesions have to make solid predictions about visual stimuli in the absence of any reported visual awareness – is a paradigmatic example of unconscious perceptual influence on conscious behavior. Newell & Shanks (N&S) are skeptical about the influence of unconscious processes on decision making in blindsight, given that blindsight seems to have alternative explanations that do not appeal to unconscious processes. To back up their claim, they cite research indicating that blindsight may just be degraded visual experience (Campion et al. 1983; Overgaard 2011; Weiskrantz 2009). A review of further empirical and theoretical work in the area of blindsight reveals that N&S's conclusions primarily based on Overgaard's (2011) findings on blindsight are premature (Brogaard 2011a; 2011b; 2011c; 2012a; 2012b; Cowey 2001; Hardin 1985; Heywood & Kentridge 2003; Stoerig & Cowey 1992).
Using a multipoint awareness measurement (PAS), Overgaard (2011) shows that the reported degree of conscious experience in blindsight correlates with the blindsight subjects' predictive success in visual tasks. These considerations appear to indicate that it is conscious perception, rather than unconscious processes, that is responsible for blindsighters' predictive behavior. For these reasons, N&S conclude that we need not appeal to unconscious processes in explaining blindsighters' success in decision making. However, Overgaard's studies do not completely rule out that the reported awareness that corresponds to predictive success in blindsight is awareness associated with the higher-order predictive act rather than genuine visual awareness. The subjects may not have the ability to distinguish between being aware of thoughts or judgments and being visually aware of a visual stimuli (Brogaard 2011a; 2012b), in which case the PAS...