The role of selective attention in short-term memory and goal-directed behavior

Selective attention enables the prioritization of goal-relevant aspects of our sensory environment in order to guide our actions, or to store goal-relevant information in short-term memory. Yet, it remains largely unclear how attention prioritizes goal-relevant information. For example, selective attention may enhance processing of goal-relevant information, suppress processing of distracting information, or both. The research presented in this dissertation examined the neurophysiological mechanisms through which selective attention supports visual short-term memory and action selection using electroencephalography, focusing on the role of brain oscillations and modulations of sensory activity. A first question concerned if selective attention predominantly modulates sensory processing during perception, or may also support maintenance of stored representations to optimize behavior. A second question concerned whether attentional modulation of anticipated and unanticipated irrelevant information rely on similar neurophysiological mechanisms. Thirdly, we addressed whether these mechanisms generalize across different sensory dimensions during action selection.
Results provided supporting evidence for an important role of selective attention in action selection, and during both short-term memory encoding and maintenance. However, they also revealed that attentional selection is often imperfect, especially when irrelevant information cannot be anticipated. Whereas interregional modulation of alpha oscillations was associated with filtering of anticipated irrelevant information, filtering of unanticipated distraction relied, at least partly, on representation-specific sensory modulations. Furthermore, individuals differed markedly in the degree to which they exhibited attentional modulation of irrelevant information for different sources of interference, demonstrating the importance of an individual differences approach to increase our understanding of the neural mechanisms that enable selective processing of goal-relevant information.