A functionalist criterion for arbitrating between theories of consciousness is not theory-neutral because it focuses on functional equivalence between systems. Empirical theories of consciousness are mechanistic rather than functionalist, so such criteria are not helpful for arbitration.
Conservative criterion placement in subjective awareness judgments inflates neural effect sizes for both conscious and unconscious processing, while liberal placement reduces them. Simulations and two EEG studies show that the commonly used Perceptual Awareness Scale does not protect against this confound. The findings indicate that response criterion placement threatens the construct validity of neural measures of consciousness.