Grasping a Chestnut Burr

This work aimed to assess the role of manual laterality in action coding strategies and, subsequently, in environmental features relevant for each hand's action. Relying on Eder and Hommel's (2013) proposal, we distinguished stimulus-related and end state-related consequences in a Simon paradigm where right-handed participants were divided into two groups, one responding with gloves and one without. Two objects were presented pictorially: one for which sensory consequences of grasping were negatively valenced (a chestnut burr), and one for which they were positively valenced (an apricot). By these means, stimulus and end-state effects could be assessed separately, along with the relevance of each feature of the experimental settings. Results showed that the use of one's dominant or non dominant hand gives rise to different repercussions of stimulus-related and end state-related effects on response: Responses made with the right (dominant) hand were based on an elaborated coding (representing features of stimulus-related and end state-related consequences of action). In contrast, responses made with the left (non dominant) hand seemed to be based on a less elaborated coding (not taking into account end-state consequences of an action).