title: Extended Neural Metastability in an Embodied Model of Sensorimotor Coupling.
abstract: The hypothesis that brain organization is based on mechanisms of metastable synchronization in neural assemblies has been popularized during the last decades of neuroscientific research. Nevertheless, the role of body and environment for understanding the functioning of metastable assemblies is frequently dismissed. The main goal of this paper is to investigate the contribution of sensorimotor coupling to neural and behavioral metastability using a minimal computational model of plastic neural ensembles embedded in a robotic agent in a behavioral preference task. Our hypothesis is that, under some conditions, the metastability of the system is not restricted to the brain but extends to the system composed by the interaction of brain, body and environment. We test this idea, comparing an agent in continuous interaction with its environment in a task demanding behavioral flexibility with an equivalent model from the point of view of "internalist neuroscience." A statistical characterization of our model and tools from information theory allow us to show how (1) the bidirectional coupling between agent and environment brings the system closer to a regime of criticality and triggers the emergence of additional metastable states which are not found in the brain in isolation but extended to the whole system of sensorimotor interaction, (2) the synaptic plasticity of the agent is fundamental to sustain open structures in the neural controller of the agent flexibly engaging and disengaging different behavioral patterns that sustain sensorimotor metastable states, and (3) these extended metastable states emerge when the agent generates an asymmetrical circular loop of causal interaction with its environment, in which the agent responds to variability of the environment at fast timescales while acting over the environment at slow timescales, suggesting the constitution of the agent as an autonomous entity actively modulating its sensorimotor coupling with the world. We conclude with a reflection about how our results contribute in a more general way to current progress in neuroscientific research.
authors.affiliation: Department of Computer Science and Systems Engineering, University of ZaragozaZaragoza, Spain; Department of Psychology, University of the Balearic IslandsPalma de Mallorca, Spain; ISAAC Lab, Aragon Institute of Engineering Research, University of ZaragozaZaragoza, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Aguilera
authors.affiliation: Department of Computer Science and Systems Engineering, University of ZaragozaZaragoza, Spain; ISAAC Lab, Aragon Institute of Engineering Research, University of ZaragozaZaragoza, Spain.
authors.forename: Manuel G
authors.initials: MG
authors.lastname: Bedia
authors.affiliation: Department of Philosophy, University School of Social Work, University of the Basque Country (UPV/EHU)Vitoria-Gasteiz, Spain; Department of Logic and Philosophy of Science, IAS-Research Center for Life, Mind and Society, University of the Basque Country (UPV/EHU)Donostia - San Sebastián, Spain.
authors.forename: Xabier E
authors.initials: XE
authors.lastname: Barandiaran
keywords: criticality; embodied cognition; evolutionary robotics; metastability; neural assemblies; sensorimotor coupling; synaptic plasticity