Example stimuli used in the experiment.

<p>For each object pair an action sequence was constructed, consisting of 3 action snapshots (left column, middle column and right column). The correctness of the object grasped and the grip applied to the object were independently manipulated, resulting in action sequences representing an actor (1) grasping the correct object with a correct grip (upper row), (2) grasping the correct object with an incorrect grip (2^nd row), (3) grasping the incorrect object with a correct grip (3^rd row) or (4) grasping the incorrect object with an incorrect grip (bottom row).</p

ERPs relative to the onset of the 2^nd picture.

<p>ERPs relative to the onset of the 2^nd picture for a selection of central electrodes. Topographical plots represent the difference between Incorrect and Correct Objects (upper panel) and the difference between Incorrect and Correct Grips (middle panel. The lower panel reflects the t-values for the comparison between the Object Effect (Incorrect – Correct Object) and the Grip Effect (Incorrect – Correct Grip). The critical t-values are marked in red and a positive t-value reflects a stronger effect of Object than of Grip and a negative t-value reflects a stronger effect of Grip than of Object.</p

Object pairs used in the EEG experiment.

<p>The left column represents tools that had a high probability of being grasped first. The right column represents target objects towards which the tools could be moved. Object pairs marked with an asterisk were used as practice trials and were not included in the main EEG experiment.</p

Schematic overview of a trial sequence.

<p>Each trial started with a fixation cross, after which the action sequence was presented, consisting of 3 action snapshots. Following the action sequence either an object question (left side) or a grip question (right side) could be presented. Mapping of the response buttons (left/right) varied between trials and was presented below the question. After the subject responded a blank screen was presented.</p

Behavioral results.

<p>Error rates in response to object questions (left graph) or to grip questions (right graph). Bars on the left represent responses to action sequences representing grasping of the correct object, bars on the right represent responses to action sequences representing grasping of the incorrect object. Light bars represent responses to action sequences representing a correct grip, dark bars represent responses to action sequences representing an incorrect grip.</p