Relationship between autistic traits and letter-recognition under attention to face-likeness: study using a henohenomoheji-type compound stimulus

This study aimed to clarify the relationship between autistic traits and letter information processing, specifically, the components of faces when attention is paid to face-like information. We created a new “henohenomoheji-type compound stimulus,” in which letters are placed in positions in such a way as to resemble a face. In Experiment 1, we examined the relationship between autistic traits and the participants’ performance in a letter-recognition task in which a henohenomoheji-type compound stimulus was used. The results showed a significant moderate negative correlation between Autism-Spectrum Quotient-Japanese Version (AQ-J) scores and letter-recognition sensitivity when the compound stimuli were arranged like a face. The letter-detection task was employed in Experiment 2 to examine how autistic traits affect tasks' performance with a lower cognitive load than in Experiment 1. We found no correlation between AQ-J scores and letter-detection sensitivity with or without face-like features. These results suggest that paying attention to faces reduces the participants’ performance in letter recognition, which represents a higher cognitive load in individuals with higher autistic traits. A major implication of this study is that the henohenomoheji-type compound stimuli can be applied to several cognitive tasks, such as cognitive processing in individuals with autistic traits.