Meetings

Meeting 13

Organizational closure through neuronal signal regeneration as a possible basis for conscious awareness

Peter Cariani

Understanding of the neural basis of consciousness has been making steady progress over the last decade. We will discuss the twin problems of the necessary basis of conscious awareness, the “neural correlates of consciousness” (NCC) and the “neural correlates of the contents of consciousness” (NCCC).

Our basic philosophy is a modernized Aristotelian hylomorphism (e.g. Modrak, 1987; Graham, 1987) in which mind is the informational organization of the brain, and awareness is a necessary (but epiphenomenal) concomitant of regenerative organizations of neuronal activity. The structure of awareness supervenes on the structure of neuronal informational processes both in terms of states of consciousness and specific contents of experience (psychoneural isomorphism).

Our working hypothesis for the neuronal requisites of unified, continuous awareness is an “autopoiesis of neuronal signals.” Analogous to autocatalytic networks in the theory of life that regenerate material components and relations (autopoiesis = self-production, (Maturana & Varela, Rosen, Kauffman), we envision sets of mutually-reinforcing neuronal signals that regenerate themselves in recurrent circuits. Those mutually-compatible signal sets that exceed a threshold signal-to-background level evoke concomitant changes in awareness. Disruptions in the coherence of signal regenerations, such as through general anesthesia or seizure, would be expected to abolish awareness even as neuronal activity persists.

The framework has much in common with current ideas concerning the importance of global workspaces (Baars), ignition in recurrent/re-entrant circuits (Edelman & Tononi, Lamme, Dehaene, Pollen), a dynamic core (Tononi). However, it posits that the necessary and sufficient basis for awareness is a “circular causal”, cybernetic organizational closure of signals rather than an information-complexity threshold (Tononi’s Phi measure).

We think that the most critical barriers facing us now are lack of understanding of the central neuronal codes and computations that subserve awareness and its contents. It is much more difficult to make headway if you don’t understand exactly how information is embedded in neuronal activity (e.g. Genetics before DNA). We will discuss different possible relationships between neural activity, informational representations and operations, and phenomenal experience. How independent are mass neuronal population dynamics and informational representations? Do oscillations and/or synchronies play essential information-functional roles or are they orthogonal to the neural codes? Drawing from our own work on neural coding of auditory percepts, we will discuss what psychoneural bridge laws might look like. We will also outline speculative alternative neural timing net architectures that are based on temporal pattern spike codes, signal multiplexing and broadcast, and active regeneration of neuronal signals.