Kinematic priming of action predictions

• Published in: Current biology 2023-07, Vol.33 (13), p.2717-2727.e6
• Main Authors: Scaliti, Eugenio, Pullar, Kiri, Borghini, Giulia, Cavallo, Andrea, Panzeri, Stefano, Becchio, Cristina
• Format: Article
• Language: English
• Subjects: Biomechanical Phenomena; Humans; Intention; kinematic encoding; kinematic priming; kinematic readout; Movement; prospective information; Prospective Studies; Reaction Time
• ISSN: 0960-9822; 1879-0445
• DOI: 10.1016/j.cub.2023.05.055

The ability to anticipate what others will do next is crucial for navigating social, interactive environments. Here, we develop an experimental and analytical framework to measure the implicit readout of prospective intention information from movement kinematics. Using a primed action categorization task, we first demonstrate implicit access to intention information by establishing a novel form of priming, which we term kinematic priming: subtle differences in movement kinematics prime action prediction. Next, using data collected from the same participants in a forced-choice intention discrimination task 1 h later, we quantify single-trial intention readout—the amount of intention information read by individual perceivers in individual kinematic primes—and assess whether it can be used to predict the amount of kinematic priming. We demonstrate that the amount of kinematic priming, as indexed by both response times (RTs) and initial fixations to a given probe, is directly proportional to the amount of intention information read by the individual perceiver at the single-trial level. These results demonstrate that human perceivers have rapid, implicit access to intention information encoded in movement kinematics and highlight the potential of our approach to reveal the computations that permit the readout of this information with single-subject, single-trial resolution. •Novel kinematic priming reveals rapid, implicit access to intention information•Intention information in movement kinematic primes action prediction•Single-trial intention readout predicts the amount of kinematic priming To navigate the social environment, we often need to predict the goals and intentions of others. Scaliti et al. demonstrate that movement kinematics provides human perceivers with rapid, implicit access to intention information.