Synopsis "Movement as a Window to the Mind (in English)"
Did you know you are a mindreader? Most of us have a fundamental curiosity aboutpeople and are in fact engaging in the process of mindreading every day, as wenavigate our social worlds. For instance, we often think about what other people arethinking. On a more basic level, we even predict others' goals based on their actions, such as when they reach for and grasp objects in their environment. This thesisaimed to test and validate a classic action observation paradigm. In order to do so, three experiments were conducted to investigate action observation for goal-directedmovements. In Experiment 1, adults' eye gaze was tracked as they viewed reach-tograspmovements. Contrary to standard predictions, results did not replicate gazeproactivity according to a motor matching account. Rather, adults' eyes latched on totargets that were larger and/or nearer to the agent's hand. A motor matching accountwould have predicted that grasp type (pincer grasp or whole-hand prehension)should cue gaze proactivity to the congruent target (i.e., small object or large object, respectively). In Experiment 2, adults' reaction times were measured as they viewedthe same stimuli, but presented in static rather than dynamic format. Similarly toExperiment 1, adults' response times were faster to detect a target when it appearedover an object closer to the reaching hand, rather than an object farther away fromthe hand. Again, this was not in line with a motor matching account. Finally, inExperiment 3, adults' explicit probability judgements were solicited for still framestaken from the original video stimuli. Yet again, a distance effect prevailed, wherebyadults explicitly predicted that the agent's hand would contact the closer of twoobjects, even when the hand was at rest (in the absence of any motor cue). Overall, these results imply that adults are applying non-motor heuristics during actionobservation. As such, the stimuli tested in these classical studies may not be fit forpurpose, that is, they do not reliably show a motor matching effect during actionobservation in adults. The implications of these findings for future research andtheorising are also discussed.
