Adding learning degrees of freedom in biological tissues

Simple vertex models capture successfully many aspects of mechanical behavior of biological tissues, such as rigidity transitions. These cell-based models contain parameters such as preferred cell perimeters that govern the mechanics and dynamics of the system. Here, we allow these parameters to vary as new learning degrees of freedom to explore the mechanical rigidity of tissues. These additional degrees of freedom—on top of the physical degrees of freedom, namely the vertex positions—alter the energy landscape. We find that the rigidity transition can be shifted by introducing the preferred cell perimeters as transient degrees of freedom. Adding perimeter or area stiffnesses or preferred cell areas as new degrees of freedom, on the other hand, does not change the rigidity transition of tissues.