This study examined the effect that correlational attributes that promote concept formation gives to mere expsure effect for prototypes. Using the mere exposure (e.g., Zajonc, 1968) and the concept formation paradigms (e.g., Barsalou et al., 1999), Matsuda and Kusumi (2002, 2003) elucidated three points concerning. First, it was found out that concept formation with repeated exposure builds a p...