Abstract
Recent evidence reveals that observers automatically follow the direction of another’s gaze. Here we tested whether a pointing finger automatically orients spatial attention in a similar manner. We used a spatial cueing paradigm where a central pointing hand or arrow preceded a peripheral target with an SOA of 100 or 600 ms. Participants responded to the direction of the target with either a manual (Experiment 1, N = 20) or an eye-movement response (Experiment 2, N = 20) measured with a Tobii 2150 eye tracker. Whereas the manual response task requires only a covert shift of attention, the saccade response task requires an overt shift of attention. In both experiments, participants were instructed that the stimulus cues were counterpredictive of the target location on 75% of the trials. The results from Experiments 1 and 2 revealed that responses in the 100 ms SOA trials were faster when the direction of either the hand or arrow pointing stimulus was congruent with the target location. By contrast, responses in the 600 ms SOA trials were faster when the target was incongruent with the stimulus cue. An analyses of the direction of the first saccade in the eye-movement task provided converging evidence that orienting responses were automatically cued by the pointing hand and arrow. It is also noteworthy that the percent errors in Experiment 1 were below 2%, but the percent errors in Experiment 2 were considerably higher (ranging from 8% to 16%). This difference between the errors occurring in the overt and covert tasks is substantial and suggests that it is more difficult to inhibit an eye movement than a keypress activated automatically in response to a social stimulus.
Meeting abstract presented at VSS 2013