Reflexive social attention is mapped according to effector-specific reference systems

Studies exploring reflexive joint attention report that attention is more powerfully captured by interfering social signals (such as others' gaze or hand orientation) than by non-biological directional cues (such as an arrow). However, what remains unknown is whether these effects are mapped in purely spatial or in body-part specific reference frames. Changes of a central, black fixation point into blue or orange were the imperative instruction signal for the experimental subjects to make a leftward or a rightward movement (saccades in Study 1 and hand pointing in Study 2) while ignoring distracting stimuli (leftward or rightward oriented gaze, hand pointing or arrow). Gaze and pointing hand distracters that were directionally incongruent with the instruction cue impaired the goal-driven saccadic and pointing performance, respectively. This pattern of results indicates that reflexive social attention is mapped not only in spatial but also in body-part specific reference frames.