Case Study: The application of DSI-like metrics to cardiac and physiological networks*

Sometimes, discoveries or insights in one field of study can have considerable potential impact in other apparently unrelated domains. An example of this is a paper published by the Oxford physiologist Professor Denis Noble in 2017, “Evolution viewed from physics, physiology and medicine” (Royal Society Interface Focus, 7(5), 20160159). 

This article, situated at the intersection of evolutionary theory, systems physiology and physics, articulates a view of living processes in which stochasticity is not a defect to be averaged away but a fundamental resource to be organised and harnessed by multi‑level biological networks. 

Independently of this work, Benedict Rattigan had been developing dynamic symmetry theory. The subsequent encounter between Noble and Rattigan suggested that these two lines of thought might be mutually illuminating, especially for understanding physiological regulation and cardiac dynamics.

Their meeting in 2019 arose not through a planned collaboration but through a convergence of interests around complexity, purpose and biological organisation. At the time, Rattigan was formulating dynamic symmetry theory as a general framework for thinking about how systems negotiate polarities and sustain adaptability, without detailed awareness of Noble’s 2017 Royal Society paper on evolution and stochasticity. 

The encounter revealed striking parallels between Noble’s emphasis on downward causation, multi‑scale feedback and the harnessing of stochasticity, and Rattigan’s focus on dynamic symmetry as the structural–dynamical balance that underpins resilience and innovation. 

The paper below (currently awaiting peer-review) explores those parallels in depth, with a particular focus on the heart as a paradigmatic physiological network in which constraint and variability must be continuously balanced.

*Note: “Case study” here refers to a worked conceptual and methodological application rather than a completed data‑driven study.

Further reading: The Interdependence of Order and Disorder: How complexity arises in the living and the inanimate universe, by Denis Noble

Dynamic Symmetry and the Harnessing of Stochasticity: A Synthesis of Denis Noble’s Biological Relativity, by Benedict Rattigan