Structure-Function Relationships behind the Phenomenon of Cognitive Resilience in Neurology: Insights for Neuroscience and Medicine
Abstraction of function from structure. (a) The relationships of connectivity among the nodes of a network can reside at, at least, two levels, structural and functional levels. Modifications at the structural level (black squares and lines representing damage) can be compensated by reassigning nodes and nodes’ relationships to keep invariant (or similar) the map of the process of information transfer at the level of the functional map. Left. The structural and functional map over the network are identical. Center. After damage, the structural map is modified. Degeneracy in the structure is used to compensate for the lost node (black) and another available node in the structure is allocated (green). Topologically, the functional network is equivalent to the original structural network. Right. Pluripotency is used to compensate for the lost node, while another node, but already used in the structure is allocated (red). This nevertheless maximally preserves network’s topology. (b) Illustration of the notion of degrees of freedom in structure-function relationships in the brain, and of their role in resilience.