Thoughts from the forest floor: a review of cognition in the slime mould Physarum polycephalum

Abstract

Sensing, communication, navigation, decision-making, memory and learning are key components in a standard cognitive tool-kit that enhance an animal’s ability to successfully survive and reproduce. However, these tools are not only useful for, or accessible to, animals—they evolved long ago in simpler organisms using mechanisms which may be either unique or widely conserved across diverse taxa. In this article, I review the recent research that demonstrates these key cognitive abilities in the plasmodial slime mould Physarum polycephalum, which has emerged as a model for non-animal cognition. I discuss the benefits and limitations of comparisons drawn between neural and non-neural systems, and the implications of common mechanisms across wide taxonomic divisions. I conclude by discussing future avenues of research that will draw the most benefit from a closer integration of Physarum and animal cognition research.

An evidence-based critical review of the mind-brain identity theory

“…Plant and cellular lifeforms exhibit forms of basal cognition, with abilities including adaptation, memory, communication, learning, decision-making, and problem-solving. Notable instances include the slime mold intelligent behaviors ( Reid, 2023 ) and bacterial communities’ coordinated problem-solving abilities, demonstrating that cognition is not exclusive to organisms with brains ( Dinet et al, 2021 ).…”

“…Learning processes of habituation with anticipating conditioned behavior was shown as well ( Saigusa et al, 2008 ). For an in-depth review on slime molds see also ( Reid, 2023 ).…”

Premises for a digital twin of the Atlantic salmon in its world: Agency, robustness, subjectivity and prediction

“…Rather, we follow a more applied objective to develop algorithms that represent internal mechanisms with accuracy sufficient to predict observable performance. There are several (partly competing) perspectives on the evolution of experience and decision-making (Baars, 1988;Barrett, 2017;Barron & Klein, 2016;Chittka, 2022;Del Giudice, 2023;Feinberg & Mallatt, 2016;Ginsburg & Jablonka, 2019;Godfrey-Smith, 2017;Gygax, 2017;LeDoux, 2012;Merker, 2007;Reid, 2023;Seth, 2021;Tononi & Edelman, 1998). However, they all share the key components: agency, emotion, attention, prediction and learning (see Box 1 for definitions of terms).…”

Behavioral plasticity in aneural organisms.

“…The slime mold Physarum polycephalum has become a model for studying behavioral plasticity after a report announcing that this aneural protist could solve a complex maze (Nakagaki et al, 2000; see Reid, 2023). Physarum is a large, visible to the naked eye, single-cell, amoeboid protist containing numerous nuclei and can grow pseudopodia in any direction.…”