News from CEXS-UPF
Is it possible to describe the functioning of the brain and the cell with the same mathematical laws that regulate a simple sandpile? Grain by grain, sand accumulates. Over time, the growth of the pile reaches a critical point where it is so unstable that the next grain could cause it to collapse. It is through this series of avalanches of various sizes that the sandpile - a complex system comprising millions of items - can restore its general stability. Theoretical and empirical studies suggest that biological networks when they operate on the threshold of this criticality improve their functionality in terms of information processing, robustness and evolvability.
Although some studies have attempted to explain criticality according to specific features of the system, a general theory of critical behaviour is still lacking in biological systems. In a study recently published in the journal Frontiers in Physiology, involving Sergi Valverde, visiting professor to the Department of Experimental and Health Sciences and a member of the Complex Systems Lab of the Institute of Evolutionary Biology (UPF-CSIC), and Jordi García-Ojalvo, a researcher of the Department of Experimental and Health Sciences (CEXS) at UPF, among other authors, this problem is dealt with from the perspective of complex systems, since many biological systems share the common trait that their internal organization can be described as a complex network.
In this article the authors review and discuss the recent breakthroughs published on the criticality of brain and gene networks and reflect as to the implications of the network theory in the evolutionary features of criticality.
Sergi Valverde, Sebastian Ohse, Malgorzata Turalska, Bruce J. West and Jordi García-Ojalvo (2015), "Structural Determinants of Criticality in Biological Networks", Frontiers in Physiology, doi: 10.3389/fphys.2015.00127.