Examining Sleep as a Moderator of Physiological Response to Stress Among Migraineurs

Stress and sleep disturbance are among the most frequently reported triggers of migraine. Several studies have found migraineurs have heightened physiological response and decreased rates of habituation to stressors compared to those without headache. A smaller body of literature suggests that poor sleep and high stress can interact to influence migraine, though a larger literature across chronic pain populations and the general population also supports an interactive effect between stress and sleep. No study to date has examined the extent to which sleep disturbance moderates physiological response to stress among migraineurs, the findings of which may help to inform understanding of migraine mechanisms and treatment development strategies. The present study sought to experimentally examine the effect of sleep quantity and quality on cardiovascular reactivity to a repeated stressor (i.e., speech task) and to determine if an observed stress-sleep relationship varies as a function of headache diagnosis (i.e., migraine vs. non-headache). Results indicated that participants with migraine and those without headache had different systolic blood pressure in response to stress between timepoints depending on their quantity of sleep (F(2, 130) = 4.742, p = .010, R-squared change = .068), indicating a significant interaction effect. However, the nature of the interaction was different from expected, as there was an inverse relationship between sleep quantity and SBP during the initial stressor task among participants without headache, while no such relationship existed for migraineurs. Rather, migraineurs’ SBP during the initial stressor task was similar regardless of their sleep quantity. Interactive effects were not found for other physiological measures or for sleep quality. Results suggest that sleep may not be a protective factor against heightened stress response among migraineurs. Future studies are needed to further examine relationships between these factors and possible mechanisms behind any interaction effects

Development of a vehicle road load model for ECU broadcast power verification in on-road emissions testing

West Virginia University (WVU) has become an industry leader in heavy-duty emissions testing and is continuously improving and updating their testing goals, procedures, and quality. As emissions testing is conducted at WVU in a real-world, on-road environment, engine parameter values are read through the test vehicle\u27s electronic control unit (ECU) and recorded for use in data reductions. One significant value that is recorded by the WVU emissions measurement system is the ECU engine power output. Theses values are recorded and used to report vehicle\u27s brake specific emissions values over a prescribed open-road test route. Because of the fact that the engine power output values reported by the vehicle\u27s ECU are difficult to accurately measure elsewhere, they are assumed to be accurate and used in the data reduction process. This presented the need for a study to develop a model to validate the ECU power output data. The objective of this work was to develop such a model that accurately produces values for the test vehicle\u27s road load while in use. By developing this model, the quality of the results of the on-road emissions testing performed by WVU could be monitored and confirmed.;By measuring three parameters of a vehicle test, this model was developed and produced accurate results. (Abstract shortened by UMI.)