Perfusion Changes in Patients After Cardiac Surgery: Evidence from an N-Back Working Memory Task.

Todd B. Harshbarger¹, Jeff Browndyke², Allen W. Song¹, Joseph Mathews²

Patients who have undergone cardiac surgery often develop cognitive impairments. In this study, we collected perfusion data in patients pre- and post-surgery while performing a working memory task. Quantitative maps of cerebral blood flow were created, and measures of both global and local changes after surgery were made. Although the global level of perfusion does not change, localized areas in regions known to be active during the task display increased perfusion. Further research is needed to determine if these are neuronal compensatory effects or vascular changes in the brain.