Evaluation of Perceived Impressions of Response Timing and Motion Patterns in Nodding Behavior in Response to Users’ Gaze at Character

Abstract

This study investigates how response timing and nodding motion in gaze-driven interfaces affect impression and empathetic feedback with childcare support discussed as one potential application. Two factorial experiments were conducted: Experiment 1 manipulated response timing (0ms, 300ms, 1000ms, and no response) to evaluate its impact on impressions such as familiarity, activeness, and sincerity, as well as empathy and reassurance. Experiment 2 examined how different types of nodding motions influence the perception of response timing and overall impression. Results showed that a 300ms response delay was rated highest for empathy and reassurance, while activeness was rated highest for immediate (0ms) responses. The physical characteristics of nodding motions (depth, frequency, duration) significantly affected impression ratings, with certain motions perceived as more familiar or sincere. Importantly, the results suggest that impression characteristics may mediate the effect of nodding motion on empathetic feedback, suggesting that design should prioritize the user’s perceived impression rather than simply optimizing motion parameters. These findings provide foundational knowledge for signing low-burden, empathetic nonverbal interactions, with childcare support interfaces as a representative application, emphasizing the importance of combining optimal response timing with nodding motions that evoke positive impressions.