Bottom-up and top-down information determinants of naturalistic trait impression updating

Understanding others’ personality traits plays an important role in guiding social interactions. In daily life, people update their impressions of others’ traits dynamically based on short encounters. Here, across four studies (N = 1,296), we used naturalistic experimental paradigms and novel computational methods to characterize how targets’ multimodal behavior and perceivers’ own characteristics shaped dynamic trait impression updating during naturalistic video viewing. By examining a comprehensive set of 38 traits, we found that people updated face-based first impressions of many traits after viewing autobiographical audiovisual narratives told by targets (Study 1). By experimentally removing verbal, visual, and vocal cues from the videos, we found that the dynamics of impression updating were predicted by the unique information in what the target said, how they moved, and how they sounded, as well as the shared information among these cues (Study 2). By computationally quantifying multimodal cues as they naturally co-evolved in unedited videos, we confirmed the unique roles of these cues and their sub-features (e.g., facial muscle movements, head movements, accumulated narrative content, energy structure of a voice) in driving the dynamic process of trait impression updating (Studies 3 and 4). We also found that perceivers’ own affect, attitudes, and personality predicted the dynamics of trait impression updating. These findings move beyond prior literature on one-shot impressions and the magnitude of impression changes by comprehensively characterizing the informational drivers and their unique roles for how trait impressions dynamically unfold in naturalistic contexts.