Priming of mental operations by masked stimuli.

Motor responses can be affected by visual stimuli that have been made invisible by masking. Can masked visual stimuli also affect nonmotor operations that are necessary to perform the task? Here, I report priming effects of masked stimuli on operations that were cued by masking stimuli. Cues informed participants about operations that had to be executed with a forthcoming target stimulus. In five experiments, cues indicated (1) the required response, (2) part of the motor response, (3) the stimulus modality of the target stimulus, or (4) the task to be performed on a multidimensional stimulus. Motor and nonmotor priming effects followed comparable time courses, which differed from those of prime recognition. Experiment 5 demonstrated nonmotor priming without prime awareness. Results suggest that motor and nonmotor operations are similarly affected by masked stimuli.