The impact of facial expressions on space- and object-based attention by gaze cues.

Previous studies have shown that social cues, such as gaze direction, typically direct space-based attention rather than object-based attention in the two-rectangle paradigm. However, the inherent connection between eye gaze and facial expressions leaves unresolved questions about whether and how facial expressions influence gaze-driven selective attention. The present study aimed to explore the effects of facial expressions on both space- and object-based attention triggered by gaze cues. We used a modified two-rectangle paradigm incorporating gaze information from negative, neutral, and positive facial expressions while manipulating cue-target stimulus onset asynchrony (SOA) at 150 ms, 300 ms, and 600 ms. The results revealed that facial expressions did not modulate space-based attention; however, distinct patterns emerged for object-based attention. Specifically, negative facial expressions did not induce object-based attention, while positive facial expressions produced a stronger object-based attentional effect compared to neutral expressions at 150 ms and 300 ms SOA conditions. These findings suggest that facial expressions in gaze cues elicit object-based attention, with positive expressions guiding attention to the entire object. This study provides new empirical evidence for investigating of social cognition and selective attention.