The emotional S1-S2 paradigm for exploring brain mechanisms underlying affective modulation of expectancy
From the past decade to date, research on the interactive brain mechanisms between attention and emotion studied through event-related potentials (ERPs) has increasingly grown. This brain signal reflects fast and swift cognitive processing due to its excellent temporal resolution and it has become a suitable tool in order to study several issues concerning cognitive processing. In this chapter we present a detailed description of an `emotional variant¿ of the S1 (cue)-S2 (target) task that has been typically used to explore vigilance-related attention. The application of the emotional S1-S2 paradigm elicits an affective modulation effect on a brainwave that has been related to expectancy, the early Contingent Negative Variation (eCNV). In this chapter we will present several issues concerning different methodological aspects to take into account when applying this paradigm and some details related to the procedures of quantification and analysis of the ERP data. Finally, some findings obtained through the use of the emotional S1-S2 protocol are summarized and some of its different application possibilities (e.g., clinical samples) are proposed.