Since we rarely view our own body movements in our dailylives, understanding the recognition of self-body movementcan shed light on the core of self-awareness and on therepresentation of actions. We first recorded nine simple andnine complex actions performed by individual participants,who also subsequently observed nine videos displayed on thescreen and imitated these actions. After a delay period of 35-40 days, participants were asked to identify their self- bodymovements presented as point-light displays amongst threeother actors who performed the same actions. Participants wereable to recognize themselves solely based on kinematics inpoint-light displays. However, self-recognition accuracyvaried according to the complexity of performed actions, withmore accurate self-recognition for complex than simpleactions. The ability of self-recognition with simple actionsshowed a significant relation with autistic traits (negativerelation: poorer self-recognition accuracy with more autistictraits), schizophrenic traits (quadratic non-linear relation,participants with the median degree of schizophrenia traitsperformed better than participants at the extremes), and withimitation actions and motor imagery traits (linear relation:increased self-recognition accuracy with greater motorimagery). We also found that participants did not recognizeactions that only required visual experience but could identifytheir self-generated actions that required motor experience,underscoring the importance of motor experience to therepresentation of self-body movements.

Although humans can recognize their body movements in point-light displays, self-recognition ability varies substantially across action types and participants. Are these variations primarily due to an awareness of visually distinct movement patterns, or to underlying factors related to motoric planning and/or individual differences? To address this question, we conducted a large-scale study in self-action recognition (N = 101). We motion captured whole-body movements of participants who performed 27 different actions across action goals and degree of motor planning. After a long delay period (~ 1 month), participants were tested in a self-recognition task: identifying their point-light action amongst three other point-light actors performing identical actions. We report a self-advantage effect from point-light actions, consistent with prior work in self-action recognition. Further, we found that self-recognition was modulated by the action complexity (associated with the degree of motor planning in performed actions) and individual differences linked to motor imagery and subclinical autism and schizotypy. Using dynamic time warping, we found sparse evidence in support of visual distinctiveness as a primary contributor to self-recognition, though speed distinctiveness negatively influenced self-recognition performance. Together, our results reveal that self-action recognition involves more than an awareness of visually distinct movements, with important implications for how the motor system may be involved.