Can conscious experience affect neural states via “downward causation”?

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My students have been asking questions about how the chemical processes in the brain are related to emotions.

This is forcing me to really think about how neurophenomenology should relate to dualism, monism, panpsychism, reductionism, elimitivism, and other stances regarding conscious states and neural states.

In a broad sense I favor Merleau-Ponty’s notion of la corporeal, which conceives of that physiological body that is observed by science as in some fundamental sense the same as my body, my flesh, embodied me, the foundation of my experience.

What about the specific, in principle falsifiable question of whether conscious experience can affect neural states via “downward causation”? I found a few resources to address this question.

I first encountered this idea in an Omni interview with the eminent neuroscientist Roger Sperry:

“In wrestling with the split-brain problem, I realized that this kind of interaction with objects requires that consciousness have a causal impact on brain activity. Consciousness can be viewed as a higher emergent entity that supercedes the sum of it’s right and left brain awareness”

Once you have an interesting idea like that to ponder, you are primed for more! For what’s it worth, Dave Demaris, coming from a neurodynamics, computational neuroscience and systems engineering background, tells me he finds nothing controversial about downward causation from mind to brain. I suspect Francisco Varela was ahead of all of us on this, I am still very slowly working my way through his massive output. Someone needs to get Walter Freeman to get his views on this documented (for what’s it worth, Walter told me in 2001 his general views on mind and brain are closer to Varela’s than people seem to think).

I found thoughtful, provocative writing from the clinical psychologist Brian Kohler at http://www.isps-us.org/koehler/neurophenomenology.htm:

“Neurophenomenology relies on two key concepts: emergence and embodiment. Emergence extends and enriches the notion of natural causation, without violating the supposed causal closure of physics. Emergence entails both upwards and downwards causation. Embodiment provides the tools for criss-crossing the ‘explanatory gap’ between first-person phenomenology and third-person neuroscience. This is not closing the gap via reductionism, rather it is a way of moving productively from the one domain to the other by way of a third mediating domain, ie, dynamical systems.Varela and Thompson (2003) noted:“Given that the coupled dynamics of brain, body, and environment exhibit self-organization and emergent properties at multiple levels, and that emergence involves both upwards and downwards causation, it seems legitimate to infer that downwards causation may occur at multiple levels in these systems, including that of…cognitive acts in relation to local neural activity” (p.276).

These authors cited the idea of J. A. S. Kelso who wrote: “Mind itself is a spatiotemporal pattern that molds the metastable dynamic patterns of the brain.” Walter Freeman described consciousness as an order parameter and state-variable operator in the brain that mediates relations among various neurons. According to Freeman, mind is not epiphenomena, rather, it plays a crucial role in intentional behavior-it is the task of the neurodynamicist to define and measure what that role is. Another good example, and clinically useful, of ‘downward causation,’ is recent research on human epileptic activity. There is evidence that subjects can voluntarily affect the conditions leading to the initiation and course of seizure activity ( see Francisco Varela & Evan Thompson’s “Neural synchrony and the unity of mind: a neurophenomenological perspective” in Axel Cleermans’ edited volume “The Unity of Consciousness: Binding, Integration, and Dissociation” published in 2003 by Oxford University Press).

Epileptogenic zones are embedded in a complex network of other neural regions that actively participate in mental life. These networks are multiple and distributed over a large scale. The global level of integration ( the result of ‘upwards causation’ ) may produce ‘downwards’ effects, acting eventually upon the local level of the epileptogenic zones. Recent studies by Varela and colleagues have demonstrated that there are deterministic temporal patterns within the apparent random fluctuations of human epileptic activity, and that these patterns can be modified during cognitive tasks (Le Van Quyen et al 1997). Varela and Thompson (2003) concluded: “ …the act of perception on the part of the patient contributes in a highly specific manner, via the phase synchrony of its associated neural assembly…to pulling the epileptic activities towards particular unstable periodic orbits. Thus downwards causation need be no metaphysical will-o’-the wisp, but can be an empirically tangible issue” (p. 277). “

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