How different is Action Recognition across Cultures? Visual Adaptation to Social Actions in Germany vs. Korea

The way social actions are used in everyday life to interact with other people differs across various cultures. Can this cultural specificity of social interactions be already observed in perceptual processes underlying the visual recognition of actions? We investigated whether there were any differences in action recognition between Western and East Asian cultures by testing German and Korean participants using questionnaires and a visual adaptation paradigm. First, both German and Korean participants had to recognize and describe four different social actions (handshake, punch, wave, fistbump) presented as brief movies of point-light-stimuli in an action naming task. Then, they had to rate similarities of actions in terms of their motion and meaning for all possible action pairs. Finally, we examined the underlying representations for each action using an action adaptation paradigm. Participants were repeatedly exposed to different action stimuli in separate experimental blocks. After being adapted in each experimental block, participants had to categorize ambiguous test stimuli in a 2-Alternatives-Forced-Choice (2AFC) task. The test stimuli were created by linearly combining the kinematic patterns of two actions such as a punch and a handshake. We measured the degree to which each of the four adaptors biased the perception of the subsequent ambiguous test stimulus for German and Korean participants. In the action naming task, the actions handshake, punch and wave were correctly recognized by both Germans and Koreans, but most Koreans failed to recognize the correct meaning of a fistbump. In the similarity rating task, both German and Korean participants showed highly consistent ratings. Also in the adaptation task, Germans and Koreans also showed remarkable similarities regarding the relative perceptual aftereffects induced by the adaptation to different action stimuli. In sum, our results imply a surprising consistency and robustness of action recognition processes across different cultures. Our methodology is suitable for further mapping different human actions in the brain, and these results may have also implications for the development of automated action recognition technologies for the field of social robotics and machine learning