The holobiont mind: A bridge between 4E-cognition and the microbiome

Abstract

All life on earth is intrinsically linked. At the very foundation of everyevolutionary interaction are microorganisms; integral components in thecomposition of both organisms and ecosystems. This perspectivechallenges the traditional conception of monogenetic biologicalindividuals, suggesting living beings are actually composite multi-speciescomplexes; holobionts. In the present article, we introduce the conceptof the holobiont mind; a biogenic conception of cognition. Wefurthermore expand on the idea of the mind as the emerging product ofmulti-genomic morphology of a composite agent, in ever changinginteraction with its ecological niche. We briefly review recent evidence onthe Brain-Gut-Microbiome axis and the Microbiome of the BuiltEnvironment in order to provide a bridge between the Holobiont Mindand the 4E approach to Cognition, two complementary lines of evidencethat have not been linked before, opening novel venues for research withdirect impact on health and disease.

The 4E approach to the human microbiome: Nested interactions between the gut‐brain/body system within natural and built environments

“…Here, we recognize and hypothesize that microbiome research not only supports the 4E perspective to cognition but also is interlinked with it, as mental processes are highly dependent on microbial influences delimited by similar dimensions of the 4E perspective. Thus, the 4E approach to the human microbiome (Figure 1) considers the global sets of microbial ecosystem networks that i) are part of an individual's body (i.e., commensal bacteria) forming a composite organism [ 23 ] ; ii) are encountered by a person across their lifetime, namely the external living environment (i.e., workplace, transport, habitational space, ecological niche); and iii) are dependent on behavioral activities developing on people's lifestyles (i.e., diet, physical activity). These complex microbial networks have an ever‐evolving circular causal relation to a person's cognition, changing, and being changed by their history.…”

“…Recent developments within the field of human‐microbial ecology suggest a new understanding of humans and other macro‐organisms as holobionts comprising all the cells belonging to each individual, as well as the collection of viral, fungal, bacterial, and other commensal organisms inhabiting them. [ 23,92 ] In addition, both host and microbiota genomes constitute the hologenome . [ 93 ] Both holobiont and hologenome concepts entail a radical departure from traditional monogenetic perspectives, suggesting that individuality must be reframed (or at least, seriously discussed).…”

“…Thus, the ontological, epistemological, and ethical aspects of the 4E perspective offer a virtuous interaction with modern scientific advancements when measuring and analyzing neurobehavioral states, ushering in a new frontier for basic and translational research. [ 6,21–23 ] Adopting a holistic and integrative view of cognition, its components, and its functional dynamics is ethically necessary 1 in current times. [ 20,24,25 ] These ideas positively impact health sciences by i) decreasing the gap between basic and translational science through the integration of cross‐species, cross‐method research and therapeutics [ 26 ] and ii) providing a framework where unbalanced (neuro)physiological states, altered subjective experiences, uncoupled behavioral states, and disturbed interpersonal interactions fit together, depending on each other.…”

Do not burn these gentle bridges: an empirical framework based on the 4E perspective is necessary, pertinent, and timely

“…This body of evidence suggests that, perhaps, it is better to think of living beings as composite multi-species complexes (Gilbert et al, 2012;Zilber-Rosenberg & Rosenberg, 2008). Considering these aspects, Palacios-García & Parada García & Parada (2021), briefly refers to the Enactive approach (p.1-2) and mentions the existence of research on the gut-brain axis (p.2). After this, the authors misread the definition of the holobiont mind concept, explicitly suggesting that a new "theory of mind" was being proposed (p.2).…”

“…Then, how can we thus understand the Holobiont mind? Palacios-García & suggest the generation of empirical research programs based on the 4E perspective may hold the answer.Furthermore, no indications, suggestions, or intent to create a "new theory [...] which seeks to emphasize one factor in which the body affects cognition over the rest" (Molero-Ramírez & Carro-Godoy, 2022 p.2) can be found inPalacios-García & Parada (2021). This claim, based on a misreading and misunderstanding from the commentators, clearly opposes the sole concept of cognitive agents as composite multi-species complexes, and is far from the ideas encompassed in the target article.…”