Consciousness seeks simplicity: repetitions trigger illusory awareness in implicit statistical learning

Implicit statistical learning (ISL) is a fundamental cognitive process through which we extract regularities from environmental stimuli. While ISL has several characteristics of unconscious processing (e.g., it operates unintentionally, produces subjectively unconscious knowledge), participants in ISL experiments always report some fragmentary conscious knowledge. Thus, the notion that ISL is truly an unconscious process has been the subject of perpetual debates. In the present study, we challenge the assumption that these conscious reports reflect direct access to the acquired knowledge. Building on predictions from key theories of consciousness and suggestive evidence in the literature, we tested the hypothesis that participants’ conscious reports in ISL reflect a post hoc conscious model of their non-conscious knowledge. Across two artificial grammar learning experiments, participants were exposed to sequences of stimuli (letters, faces, or body movements in VR) generated by different artificial grammars. In a subsequent test, they decided whether novel strings were grammatical or not and reported their subjective awareness trial-by-trial. In both experiments, we found extreme Bayesian evidence that repetitions embedded in the testing strings made participants more aware of the knowledge driving their grammaticality decisions, above and beyond their influence on responses or accuracy. This suggests that, lacking access to the true basis of their decisions, participants attributed their responses to the most salient feature available—the repetitions. Thus, we find evidence that our conscious experience can misrepresent not only the external world but also our own unconsciously learned representations.