Turing instabilities in biology, culture, and consciousness? On the enactive origins of symbolic material culture

Abstract

It has been argued that the worldwide prevalence of certain types of geometric visual patterns found in prehistoric art can be best explained by the common experience of these patterns as geometric hallucinations during altered states of consciousness induced by shamanic ritual practices. And in turn the worldwide prevalence of these types of hallucinations has been explained by appealing to humanity's shared neurobiological embodiment. Moreover, it has been proposed that neural network activity can exhibit similar types of spatiotemporal patterns, especially those caused by Turing instabilities under disinhibited, non-ordinary conditions. Altered states of consciousness thus provide a suitable pivot point from which to investigate the complex relationships between symbolic material culture, first-person experience, and neurobiology. We critique prominent theories of these relationships. Drawing inspiration from neurophenomenology, we sketch the beginnings of an alternative, enactive approach centered on the concepts of sense-making, value, and sensorimotor decoupling.

A Bidirectional Link between Brain Oscillations and Geometric Patterns

“…One might even imagine that the abovementioned pattern formation mechanisms in V1 might be frequency independent but instrumental in providing, through feedback circuits, the missing shape input to frequencyselective higher brain regions (Billock andTsou, 2007, 2010). This idea is compatible with recent experimental and theoretical observations suggesting that geometric hallucinations could originate, at least in part, in higher visual brain regions (Ffytche, 2008;Kometer et al, 2011Kometer et al, , 2013Froese et al, 2013). It is also consistent with the topography of the EEG effects (Fig.…”

Neural coordination can be enhanced by occasional interruption of normal firing patterns: A self-optimizing spiking neural network model

“…We hypothesize that this ritualized mind-alteration could serve as a global neural reset. For example, certain altered states involve self-sustaining neural processes that partially decouple normal activity from environmental influence (Froese et al, 2013). More specifically, Carhart et al (2014) applied an entropy measure to neural states and found that the psychedelic state (here induced by psilocybin) is one of elevated entropy over the normal waking state.…”

The dynamically extended mind

“…The real challenge facing the DSH, therefore, is not to explain how cognition sometimes becomes extended, but rather how our relatively stable sense of self is maintained even in the face of continous sensorimotor and social extension. Accordingly, the nervous system's endogeneous activity deserves a closer look, in particular in terms of those processes that allow a temporary decoupling from ongoing interactions [63].…”