Organisms endowed with neuromechanical circuits, such as the locomotor networks described for the lamprey, continuously interact with the environment, forming circular functional loops which can be activated either by the neurons or by external physical events. Activity initiated by central neurons can initiate movements (mechanical events). Conversely, external events can activate sensory neurons which in turn activate central neurons. This sensory-motor loop is an example of a system of ‘circular causality1‘ whereby activation of the neuromechanical loop may begin at any point of the loop. Once initiated, the loops can continue as a self-generating state.
The limitation in the use of the concept of causality2 in neuroscience has been pointed out recently by Barack et al3. The concept of circular causality has been introduced by Hermann Haken the founder of the field of synergetics4. In one-way causality, an event A results in an event B. In a circular system, an event A results an event B, which in turn produces A. This is a circular system, for which there is not a single site of initiation of activity.
In ancient times, Aristotle said that living creatures are essentially self-moving and self-making entities that actively “reach out” to the world as they strive to maintain a flourishing life. Immanuel Kant was aware of this unique feature of living organisms when he stated, “an organism is both a cause and effect of itself.”5
From: https://en.wikipedia.org/wiki/Critique_of_Judgment
I will discuss further down suitable ways to portray and investigate neural loops that are subjected to circular causality.
- For example, see Raymond Noble et al (2019): Biological Relativity Requires Circular Causality but Not Symmetry of Causation: So, Where, What and When Are the Boundaries? Frontiers in Physiology 10, 827. ↩︎
- For a general discussion of causality, see: https://en.wikipedia.org/wiki/Causality ↩︎
- DL Barack et al (2022): A call for more clarity around causality in neuroscience. Trends in Neuroscience 45, P654-655. ↩︎
- Hermann Haken (1983): Synergetics: An introduction. 3rd ed. Springer Verlag.
Hermann Haken (1999): What can synergetics contribute to the understanding of brain functioning? In: Analysis of neurophysiological brain functioning. pp 7-40, Editor C Uhl, Springer-Verlag. ↩︎ - Immanuel Kant (1790): Critique of judgement. Part 2 Critique of teleological judgement. Translated by WS Pluhar, Hackett Publishing Co. ↩︎