Giving subjects the eye and showing them the finger: socio-biological cues and saccade generation in the anti-saccade task.
Pointing with the eyes or the finger occurs frequently in social interaction to indicate direction of attention and one's intentions. Research with a voluntary saccade task (where saccade direction is instructed by the colour of a fixation point) suggested that gaze cues automatically activate the oculomotor system, but non-biological cues, like arrows, do not. However, other work has failed to support the claim that gaze cues are special. In the current research we introduced biological and non-biological cues into the anti-saccade task, using a range of stimulus onset asynchronies (SOAs). The anti-saccade task recruits both top-down and bottom-up attentional mechanisms, as occurs in naturalistic saccadic behaviour. In experiment 1 gaze, but not arrows, facilitated saccadic reaction times (SRTs) in the opposite direction to the cues over all SOAs, whereas in experiment 2 directional word cues had no effect on saccades. In experiment 3 finger pointing cues caused reduced SRTs in the opposite direction to the cues at short SOAs. These findings suggest that biological cues automatically recruit the oculomotor system whereas non-biological cues do not. Furthermore, the anti-saccade task set appears to facilitate saccadic responses in the opposite direction to the cues.
Washington Singer Laboratories, Psychology, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QG, UK.
Nicola J
NJ
Gregory
Timothy L
TL
Hodgson
D000293:Adolescent; D000328:Adult; D001288:Attention; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D009949:Orientation; D010364:Pattern Recognition, Visual; D011930:Reaction Time; D012438:Saccades; D012660:Semantics; D057190:Stroop Test; D055815:Young Adult