Unconscious Grouping of Chinese Characters: Evidence from Object-based Attention *

To show that, in reading, a fundamental and unconscious perceptual process occurs beyond the current fixation, we examined whether peripherally presented characters of Chinese words in such extreme viewing conditions could be grouped when some characters were rendered invisible while others were visible. We presented a pair of two-character Chinese words and indexed whether the visible and invisible characters that formed a word could be grouped together by the effect of same-object advantage—an index used to indicate the formation of perceptual grouping and the basis for attentional selection (i.e. object-based attention). Results revealed a difference in the judgments of prior entry that would otherwise be equivalent between two concurrent targets in a cued temporal-order judgment task: the target that appeared in the cued word was judged to appear first more frequently than the other target that appeared in the uncued word. The results suggest that a perceptual grouping was formed for two-character words between visible and invisible constituent characters. While grouping within two-character words occurred, the invisible characters remained invisible in most of the trials, suggesting that this grouping occurred unconsciously. This implies that, in reading, characters presented in the peripheral region can be grouped into words even without the readers’ awareness of all the constituent characters, and such unconscious grouping can facilitate fluent reading by aggregating the texts into fewer meaningful units and thus reduce the number of fixations needed.