When is cognitive penetration a plausible explanation?

Albert Newen and Petra Vetter argue that neurophysiological considerations and psychophysical studies provide striking evidence for cognitive penetration. This commentary focuses mainly on the neurophysiological considerations, which have thus far remained largely absent in the philosophical debate concerning cognitive penetration, and on the cognitive penetration of perceptual experiences, which is the form of cognitive penetration philosophers have debated about the most. It is argued that Newen and Vetter's evidence for cognitive penetration is unpersuasive because they do not sufficiently scrutinize the details of the empirical studies they make use of-the details of the empirical studies are crucial also when the studies are used in philosophical debates. The previous does not mean that cognitive penetration could not occur. Quite the contrary, details of the feedback connections to the visual perceptual module and one of the candidates presented by Newen and Vetter suggest that cognitive penetration can occur in rare cases.