Biological & Soft Matter Seminar: Facial Blood Flow Under Muscle Regulation as a Percolation Problem

Abstarct:

Percolation theory is widely applied to various physical, biological and social phenomena typified by a network structure and critical behavior. The facial vascular network is a fascinating system with a possible role in emotional regulation, a field with massive implications in various scientific domains, which has eluded scientists for decades. We experimentally studied whether the interplay between facial muscles and blood vessels can be expressed in percolation terms to better understand this network's function. To this aim we constructed a simple model, based on the Cayley tree, with modifications designed to mimic the properties of facial blood vessels, and we investigated its percolating behavior. Experimentally we used a new wearable approach to map and study the behavior of facial muscles and changes in blood flow in the superficial temporal artery. We were able to demonstrate for the first time blood pulsation and detect changes in blood flow during muscle activation.  Changes in blood flow in response to muscle activation are clearly evident, exhibiting conspicuously complex responses suggesting a possible critical nature.