Externalized memory in slime mould and the extended (non-neuronal) mind

The hypothesis of extended cognition (HEC) claims that the cognitive processes that materially realise thinking are sometimes partially constituted by entities that are located external to an agent’s body in its local environment. We show how proponents of HEC need not claim that an agent must have a central nervous system, or physically instantiate processes organised in such a way as to play a causal role equivalent to that of the brain if that agent is to be capable of cognition. Focusing on the case of spatial memory, we make our argument by taking a close look at the striking example of Physarum Polycephalum plasmodium (i.e., slime mould) which uses self-produced non-living extracellular slime trails to navigate its environment. We will argue that the use of externalized spatial memory by basal organisms like Physarum is an example of extended cognition. Moreover, it is a possible evolutionary precursor to the use of internal spatial memory and recall in animals thus demonstrating how extended cognition may have emerged early in evolutionary history.     

Social cognition,artefacts, and stigmergy revisited: Concepts of coordination

A number of different coordination concepts have been developed to explain how individual activities are coordinated on a social level, and the variety of concepts shows there is an interest in many domains to find such explanations. Stigmergy being one of them, has come to be increasingly applied on various kinds of human activities. In other domains we find other concepts for explaining how environmental resources contribute to work activities or how people use them to structure their work. This paper discusses different coordination concepts, including stigmergy, articulation work, coordination mechanisms, triggers, placeholders, and entry points. The first three concepts are explicitly concerned with coordination among several agents, while the last three instead concern individual activities, but arguably they can be extended to the social level. They also bring an explicitly cognitive dimension to coordination, which is not as salient in the former concepts. The concepts discussed here do have some similarities, but also important differences. They may not be interchangeable, but they could complement each other, or contribute to further elaboration of existing concepts. The stigmergic sign, e.g., could usefully be developed to recognise qualitative differences in its role as a coordination mechanism.     

Human stigmergy: Theoretical developments and new applications

This paper contextualizes and introduces this special issue.     

Social cognition, artefacts, and stigmergy: A comparative analysis of theoretical frameworks for the understanding of artefact-mediated collaborative activity

Collective behaviour is often characterised by the so-called ‘coordination paradox’: looking at individual ants, for example, they do not seem to cooperate or communicate explicitly, but nevertheless at the social level cooperative behaviour, such as nest building, emerges, apparently without any central coordination. In the case of social insects such emergent coordination has been explained by the theory of stigmergy, which describes how individuals can effect the behaviour of others (and their own) through artefacts, i.e., the product of their own activity (e.g., building material in the ants’ case). Artefacts clearly also play a strong role in human collective behaviour, which has been emphasised, for example, by proponents of activity theory and distributed cognition. However, the relation between theories of situated/social cognition and theories of social insect behaviour has so far received relatively little attention in the cognitive science literature. This paper aims to take a step in this direction by comparing three theoretical frameworks for the study of cognition in the context of agent–environment interaction (activity theory, situated action, and distributed cognition) to each other and to the theory of stigmergy as a possible minimal common ground. The comparison focuses on what each of the four theories has to say about the role/nature of (a) the agents involved in collective behaviour, (b) their environment, (c) the collective activities addressed, and (d) the role that artefacts play in the interaction between agents and their environments, and in particular in the coordination of cooperation.