Sequential Effects in Spatial Exogenous Cueing: Theoretical and Methodological Issues. XXVII

Spatial cueing is a largely used experimental paradigm to study exogenous attention orienting, both in behavioural and neurological research. In such a paradigm participants are presented a sequence of trials that are assumed to be independent from each other. In each trial a peripheral spatial cue is presented, followed by a target peripheral stimulus; subjects are required to respond as fast as possible to targets, attempting to ignore cues. In such experiments RTs are mainly dependent to trial type (valid vs invalid) and to Cuetarget intervals (short vs long). The present study aims at investigating the hypothesis that facilitation and inhibition effects, observed in cueing experiments, can be considered analogous to sequential effects, usually observed in twochoice tasks, and then that all these effects can be explained by the very same cognitive mechanisms. Results from two cueing experiments support this theoretical explanation and highlight the relevance of taking into account sequential effects