The effect of emotional valence and age of faces on adults and children’s inattentional blindness

Inattentional blindness (IB) refers to the nature of an individual being unaware of an unexpected stimulus when focusing on an attentional task. Investigation into IB provides an innovative approach for the research of attentional bias that is connected with an individual’s immediate attentional capture. This study explored the effect of emotional valence and age of faces on the IB rates of children and adults. We employed a between-subject experimental design with a 2 (age of participants: child, adult) × 2 (age of face: child face, adult face) × 2 (emotional valence: positive, negative) method and used the classic IB task of cross judgment. The participants included 79 adults (54.63 ± 8.192 years old) and 78 children (10.62 ± 2.32 years old). The results showed that: (1) The IB rates of the two groups differed significantly. Children performed better than adults in detecting the faces appearing unexpectedly. (2) The effect of emotional valence only emerged on adult participants’ IB. Adults were significantly more likely to detect the positive-emotional faces than the negative-emotional ones. (3) The age of a face was not a significant factor to predict participants’ IB. Neither children nor adults showed a preference for the faces of a specific age (e.g., their own age). These findings revealed the distinct characteristics of attentional capture of children and adults when confronting unexpected facial stimuli.