Engaging the motor system with masked orthographic primes: A kinematic analysis

We report two experiments in which participants categorized target words (e.g., BLOOD or CUCUMBER) according to their canonical colour of red or green by pointing to a red square on the left or a green square on the right. Unbeknownst to the participants, the target words were preceded by the prime words ‘‘red’’ or ‘‘green’’. We found that the curvature of participants’ pointing trajectories was greater following incongruent primes (green BLOOD) than it was following congruent primes, indicating that individuals initiated a response on the basis of the prime and then corrected that response mid-flight. This finding establishes that the processing of masked orthographic stimuli extends down to include the formulation of an overt manual response.