Non-linear Hemodynamics of Mental Workload and Workload Transitions

Ryan McKendrick

Advisor: James C Thompson, PhD, Department of Psychology

Committee Members: Patrick McKnight, Tyler Shaw

David J. King Hall, #1024
April 22, 2016, 12:30 PM to 09:30 AM


This thesis describes the non-linear relationships between mental workload and activity dependent brain metabolism. It also describes how these relationships can be used to differentiate cognitive states, and test the consequences of transitions between different cognitive states as a result of changes in task demands and mental workload. Two studies were preformed, the first used functional near infrared spectroscopy to monitor prefrontal hemodynamics as mental workload was parametrically manipulated. The second study used the non-linear relationships observed in study one to classify task demands that would elicit different cognitive workload states for individuals in study two. Individuals transitioned between these states; changes in performance and activity dependent brain metabolisms were assessed. This thesis is aimed at providing a means to objectively classify workload states, and the effects of dynamic mental workload for those looking to maximize human cognitive performance.