Abstract
The action specific perception approach claims that ability to act on a given task changes perception of task relevant stimuli. Critics of this claim argue that a response bias occurs, not perceptual changes. The current experiments minimized response bias by giving trial by trial feedback on speed judgments. Participants were trained on two anchor speeds, a fast ball and a slow ball, then played a computer-based game of tennis. The ball moved across the screen at various speeds between the two anchor speeds. Ability to act was manipulated by having either a large paddle or a small paddle with which to block the ball. After each attempt to block the ball, participants performed a speed judgment task. Participants typically perceive the ball to move faster when using a small paddle than when they use a big paddle. We examined if this effect of paddle size on perceived speed would diminish or even be eliminated in the presence of feedback on speed judgments. In Experiment 1, participants completed pre-feedback, feedback, and post-feedback blocks with interleaved paddles size. Paddle size had a significant effect on speed judgments for all three blocks and did not diminish when feedback was given. Perhaps there was not enough feedback to alter responses, so in Experiment 2, participants received feedback during the entire experiment. Again, feedback did not diminish the effect of paddle size on speed judgments. These results support the claim that change in action ability affects perception, not response bias.
Meeting abstract presented at VSS 2015