A new look on S–R associations: How S and R link

• We investigate the perceptual specificity of the stimulus in S–R priming.
• S–R priming effects were found between the stimulus, the semantic task and the action.
• But they did not depend of the maintenance of the perceptual features of the stimulus.
• S–R priming involves a perceptually non-specific stimulus representation.

Humans can learn associations between stimuli and responses which allow for faster, more efficient behavior when the same response is required to the same stimulus in the future. This is called stimulus–response (S–R) priming. Perceptual representations are known to be modular and hierarchical, i.e. different brain areas represent different perceptual features and higher brain areas represent increasingly abstract properties of the stimulus. In this study we investigated how perceptually specific the stimulus in S–R priming is. In particular we wanted to test whether basic visual features play a role in the S–R associations. We used a novel stimulus: images of objects built from basic visual features. Participants performed a classification task on the objects. We found no significant effect on reaction times of switching vs. repeating perceptual features between presentations of the same object. This suggests that S–R associations involve a perceptually non-specific stimulus representation.