Martín-Arévalo, E. & Lupiáñez, J.
University of Granada, Spain
Attentional orienting is traditionally described as driven by either of two mechanisms: endogenous orienting and exogenous orienting. The cost and benefit paradigm has been used to study these two spatial attention mechanisms: to study the endogenous orienting, a central symbolic informative cue predicts the most likely location of target appearance, orienting attention voluntary. In contrast, for investigating exogenous orienting, an uninformative peripheral cue is used, which is supposed to involuntarily capture spatial attention. In the present work we have developed an adaptation of the cost and benefit paradigm to measure both types of attentional effects separatly, as indexed by “costs” and “benefits” orienting effects, and the “Inhibition of Return” (IOR) effect, respectively. Endogenous and exogenous cues were presented in each trial and their validity was manipulated across experiments to examine whether they have independent effects on detection and discrimination tasks. Results showed that both effect could be separately measured. Interestingly, IOR correlated negatively across participants with the Cost effect. Moreover, the attentional benefits at validly cued locations decreased with practice while the costs at invalidly cued locations were constant across blocks of trials, thus, showing an interesting dissociation between them. The possible mechanisms for these effects are discussed.