The article by Knoblich and Flach examines the correlation between perception and action, claiming that the two activities depend on each other. The initial hypothesis is based on previous academic research on the “motor theory of speech perception, the common-coding theory, and the theory of intentional schemas” (Knoblich & Flach, 2001, p. 467). The experimental design of the study focuses on the differences in the cognitive system of self-recognition and other-recognition of actions. The authors asked 104 participants to throw a dart during the first session. One week later, they asked the participants to watch the videos of the throwing motion and predict where the dart landed without showing the actual trajectory of the projectile. Participants demonstrated higher prediction accuracy of their own actions compared to throws of other people.
In this design, the independent variable is the throwing motion which participants analyze in the videos. The dependent variable is the outcome of the throw – whether the dart hit the upper, middle, or lower third of the board. The primary confounding variables included the distinctions in perception in the throwing motion and the concept of self-difference. The authors mitigated them by separating the participants into three groups during the second session. They judged either the display of a full body/face, only a body, or only an arm during the throwing motion.
The results demonstrated higher accuracy predictions for self-generated actions among participants. Hence, the authors concluded that this outcome confirmed the direct correlation between action and perception. All participants knew whether they were judging their own throws or the actions of other people, being more accurate in the judgments of self-generated actions. Moreover, the predictions were more accurate when participants could see the full faces and bodies of the people throwing darts.
Reflection and Alternative Explanation
Personally, I believe that it is a sound theory that perception and action are directly connected, but I think that the authors omitted several significant details. Knoblich and Flach primarily explain the conclusion based on the intentional schema theory, but they ignore the notion of memory. As far as I understand, participants could have matched the displays of themselves throwing a dart to past memories. In my opinion, one week is not a sufficient period between two sessions, and participants’ decision-making could have been affected by their memories of the first session instead of self-recognition bias.
Reference
Knoblich, G., & Flach, R. (2001). Predicting the effects of actions: Interaction of perception and action. Psychological Science, 12(6), 467-472.