Speaker:
Matt McGinley, Assistant Professor, Baylor College of Medicine (Houston, Texas)

Title:
Towards a mechanistic understanding of arousal and attention

Abstract:
Extensive work in the past decade in humans and animal models has demonstrated that global fluctuations in arousal, tracked by pupil size, have profound effects on brain and behavior. Mechanistic work in mice has elucidated the neural correlates in the neocortex and hippocampus, and potential causative roles of neuromodulatory systems in the reticular activating system, of coordinated fluctuations in global arousal state. A three-state model of wakefulness has emerged from this work, wherein small pupil size (low arousal) is associated with physiological signatures of drowsiness and internally generated activity patterns, mid-sized pupil (moderate arousal) is associated with behavioral task-engagement and optimal neural sensory processing, and large pupil (high arousal) is associated with task-disengaged, exploratory states. The first half of the talk will review work from the McGinley lab and colleagues, which has established a mechanistic foundation for the three-state model of wakeful states.  
From titrating coffee consumption, posture, and walking breaks, our daily experience tells us that optimizing our own arousal state is critical to successfully performing cognitive tasks. A poignant example is what happens in a classroom setting with the instructor says ‘this next section will be on the final exam;’ most students will ‘turn up’ their attention. Although familiar in our experience, there is surprisingly little work on the adaptive regulation of attentional intensity, including the role of arousal self-regulation therein. The second half of the talk will present recent work from the lab developing a challenging auditory feature-based attention task in mice designed to understand the role of arousal self-regulation in mediating motivated shifts in attentional intensity. They find that mice can exhibit >5 attention shifts, which are tightly time-locked to transitions in reward expectancy. As seen previously in simpler behaviors, a moderate arousal level was optimal for feature-based auditory attention. Critically, mice stabilized their arousal closer to the optimal arousal level during periods of high task utility, despite the potentially activating effect of large rewards. Ongoing work in the lab is focused on determining the neuromodulatory and sensory-frontal neural circuit mechanisms underlying these behavioral and pupillary patterns.  
Taken together, our results demonstrate that pupil size is a sensitive measure of global arousal state, revealing the efficacy of a 3-state model of wakefulness in accounting for spontaneous and self-regulated changes in arousal state. Further ongoing work seeks to translate this new mechanistic understanding to therapies for disorders of arousal and attention, such as Autism and ADHD.

Host: Nelson Totah, FIMM.

Zoom details:
https://helsinki.zoom.us/j/67849912706?pwd=WS9QTlExbnhSTkVoRUNWUjFTVzk5dz09

Meeting ID: 678 4991 2706
Passcode: 266069