The interference of negative emotional stimuli on semantic vigilance performance in a dual-task setting.

A large body of previous research has shown that emotional stimuli have an advantage in a wide variety of cognitive processes. This was mainly observed in visual search and working memory tasks. Emotionally charged objects draw and hold attention, are remembered better, and interfere more with the completion of the primary task than neutral ones. Therefore, it seems reasonable to assume that emotional stimuli also greatly affect sustained attention and vigilance decrement. In the present research, we investigated whether emotional stimuli demand more attentional resources than neutral ones in a dual-task paradigm. We adopted the abbreviated semantic discrimination vigilance task and measured participants' (N = 49) performance in a single-task and two dual-task settings. In the dual-task conditions, the visual semantic vigilance paradigm was combined with an auditory word recall task (with neutral or emotional stimuli). We found reduced vigilance and improved word recall performance in the emotional dual-task condition compared to the neutral dual-task and single-task conditions. The reduced performance was apparent throughout the task, while in the neutral conditions, participants' performance first increased and then dropped as time progressed. To conclude, our results indicate that emotional stimuli not only have an advantage in cognitive processing but also demand more attentional resources continuously while it is present compared to neutral stimuli. These results are consistent with the emotionality effect theory and evolutionary accounts of the neural circuits underlying motivated behaviors associated with critical survival needs.