• artificial grammar;
  • complex;
  • implicit learning;
  • serial reaction test;
  • word association test

Abstract:  A century ago, Jung looked into the unconscious through complexes by using word association tests. Jung wrote, ‘modern psychology with its investigation of complexes has opened up a psychic taboo area riddled with hopes and fears’, and complexes remain an unexplored taboo area of research. In the present study, we have investigated the influence of complexes on unconscious cognitive processing, in particular on implicit learning. We have found that complexes shown to disturb conscious cognitive processing in fact enhanced the attention of the subjects and their performance on an implicit learning task. These results suggest that complexes are not just abstractions, but have various actual influences on both conscious and unconscious processing.