Brain Mechanisms of Spontaneous and Learned Attentional Flexibility

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Project Summary Individuals regularly fluctuate over time in their readiness to shift spatial attention, referred to as attentional flexibility. Although researchers have historically attributed the control of attention to a combination of stimulus salience and behavioral goals, a growing body of work has suggested that learning plays an important role in determining the focus of attention. Learning also modulates moment-by-moment fluctuations in attentional flexibility such that individuals learn to adjust their readiness to shift attention according to the likelihood of needing to make a shift in their current environment. Adapting attentional flexibility is an important component of goal-directed behavior. Although the dysfunction of attentional flexibility learning may be a key cognitive deficit in a variety of psychiatric disorders, such as anxiety disorders, attention deficit hyperactivity disorder, schizophrenia, and substance abuse, the neural bases of learned fluctuations in flexibility remain unknown. This project will integrate existing theories on fluctuations in sustained attention, states of learned attentional flexibility, and stimulus-driven attentional orienting to ask: how do individuals anticipate task demands and adapt their readiness to shift attention accordingly? This project proposes a novel neuropsychological model to account for multiple sources of within-subject variation in shift readiness. Ongoing changes in sustained attention and attentional flexibility have been independently linked to spontaneous changes in activity within the brain’s default mode network, while attentional flexibility learning has been associated with the dorsal and ventral attentional control networks. However, the ways in which spontaneous and learned brain states interact to determine attentional flexibility, as well as the representational format of shift predictions, are unknown. Specific Aim 1 is to characterize the interaction of spontaneous fluctuations in default mode network activity and task-evoked prediction error signals in the dorsal and ventral attention networks. Specific Aim 2 is to probe the location-independence of attention shift expectation neural representations. Specific Aim 3 is to identify the mechanisms responsible for impaired attentional flexibility in individuals with high anxiety. To conduct these studies, undergraduate and master’s-level students will employ innovative techniques in cognitive neuroscience, including inverted encoding models of fMRI data and event-related potentials measured through electroencephalography. The goals of this project are to: (1) investigate the neural bases of within-subject variation in attentional flexibility and (2) to significantly strengthen the research environment at Wake Forest by including undergraduate and early graduate scientists in cutting-edge research on attentional control.