Date of Award
Master of Science
Dr. Kevin Shoemaker
Objective: This study tested whether the medial prefrontal cortex (MPFC) is differentially involved in human cardiovagal control in normotensive (NT) versus hypertensive (HT) subjects.
Design: Functional magnetic resonance imaging was combined with measures of heart rate (HR) and baroreflex sensitivity (BRS) during a 30-sec static handgrip (HG; 30% maximal strength) task.
Results: Baseline HR was higher in HT (68±3 bpm) versus NT (59±2 bpm). Cardiovagal baroreflex sensitivity was lower in HT (6.8±1.7 msec/mniHg) versus NT (16.4±2.2 msec/mmHg). During HG, HR increased similarly in HT (2±1 bpm) and NT (4±1 bpm). In NT, the HR response was associated with deactivation in the MPFC. MPFC activity did not change in HT. In 11 of the total 23 subjects, HR increased > 3 bpm and MPFC deactivation was correlated with the HR time course.
Conclusions: Overall, hypertension appears to be equivalent to normotension in terms of the HR response to HG and the MPFC-HR association
Norton, Katelyn, "Cortical Autonomic Alterations with Hypertension" (2010). Digitized Theses. 3725.