Abstract
Inhibition of Return (IOR) refers to a phenomenon that reaction times are slowed to a target that appears at a previously attended location. To investigate whether the mechanism of IOR is modulated by emotional contents of stimuli, the current study examined IOR to angry, happy and neutral faces. The speed-accuracy trade-off (SAT) function was measured to assess IOR in terms of sensitivity and processing time related to targets. Participants were required to discriminate gender of faces presenting on the cued or uncued locations under various response speeds controlled by experimenter. We have three findings: Firstly IOR to neutral faces was associated with shifts in response criterion, in line with our previous findings (Zhao et al. 2011). Secondly, IOR to emotional (angry and happy) faces was evident only at an early stage of target processing. Moreover, it was eliminated at a later stage of target processing and was reversed into a facilitation effect. According to the evolutional view, the arousal state decreased the response criterion to emotional faces which are interesting and important to us. Finally, perceptual sensitivity of gender discrimination was decreased to angry compared to neutral faces and the levels of decrement were significantly correlated to participants’ state-trait anxiety. Negative stimuli may increase the attentional demand as they might threat our chance of survival. This may lead to less attentional resource available for the discrimination task and in turn performance was impaired. In conclusion, the findings extended the evidence of IOR reflecting a criterion shift from low-level signal (e.g. ‘+’ or ‘x’) to high-level socially relevant stimuli such as neutral faces. Furthermore, it suggests that the arousing dimension of emotion interacted IOR in the response level while the valence dimension of emotion affected discrimination in the attentional level.
Meeting abstract presented at VSS 2013