Can Empirical Effects Extend the Reach of Perceptual Content?

In the debate about the reach of perceptual content, some philosophers have appealed to empirical effects as a test for the existence of high-level perception (HLP). Among these effects, perceptual adaptation and perceptual learning have played a major role. In this paper, I will discuss two skeptical challenges to relying on these effects as tests for HLP. The first challenge interrogates their nature as a perceptual process. The second challenge raises doubts regarding their usefulness in specifying the target high-level property.