https://www.theguardian.com/science/2022/apr/06/fungi-electrical-impulses-human-language-study
Mushrooms communicate with each other using up to 50 ‘words’, scientist claims
Linda Geddes Science correspondent
Wed 6 Apr 2022 00.01 BST
Last modified on Wed 6 Apr 2022 10.02 BST
Buried in forest litter or sprouting from trees, fungi might give the impression of being silent and relatively self-contained organisms, but a new study suggests they may be champignon communicators.
Mathematical analysis of the electrical signals fungi seemingly send to one another has identified patterns that bear a striking structural similarity to human speech.
Previous research has suggested that fungi conduct electrical impulses through long, underground filamentous structures called hyphae – similar to how nerve cells transmit information in humans.
It has even shown that the firing rate of these impulses increases when the hyphae of wood-digesting fungi come into contact with wooden blocks, raising the possibility that fungi use this electrical “language” to share information about food or injury with distant parts of themselves, or with hyphae-connected partners such as trees.
But do these trains of electrical activity have anything in common with human language?
To investigate, Prof Andrew Adamatzky at the University of the West of England’s unconventional computing laboratory in Bristol analysed the patterns of electrical spikes generated by four species of fungi – enoki, split gill, ghost and caterpillar fungi.
He did this by inserting tiny microelectrodes into substrates colonised by their patchwork of hyphae threads, their mycelia.
“We do not know if there is a direct relationship between spiking patterns in fungi and human speech. Possibly not,” Adamatzky said. “On the other hand, there are many similarities in information processing in living substrates of different classes, families and species. I was just curious to compare.”
The research, published in Royal Society Open Science, found that these spikes often clustered into trains of activity, resembling vocabularies of up to 50 words, and that the distribution of these “fungal word lengths” closely matched those of human languages.
Split gills – which grow on decaying wood, and whose fruiting bodies resemble undulating waves of tightly packed coral – generated the most complex “sentences” of all.
The most likely reasons for these waves of electrical activity are to maintain the fungi’s integrity – analogous to wolves howling to maintain the integrity of the pack – or to report newly discovered sources of attractants and repellants to other parts of their mycelia, Adamtzky suggested.
“There is also another option – they are saying nothing,” he said. “Propagating mycelium tips are electrically charged, and, therefore, when the charged tips pass in a pair of differential electrodes, a spike in the potential difference is recorded.”
Whatever these “spiking events” represent, they do not appear to be random, he added.
Even so, other scientists would like to see more evidence before they are willing to accept them as a form of language. Other types of pulsing behaviour have previously been recorded in fungal networks, such as pulsing nutrient transport – possibly caused by rhythmic growth as fungi forage for food.
“This new paper detects rhythmic patterns in electric signals, of a similar frequency as the nutrient pulses we found,” said Dan Bebber, an associate professor of biosciences at the University of Exeter, and a member of the British Mycological Society’s fungal biology research committee.
“Though interesting, the interpretation as language seems somewhat overenthusiastic, and would require far more research and testing of critical hypotheses before we see ‘Fungus’ on Google Translate.”
Much more at the link:
https://royalsocietypublishing.org/doi/10.1098/rsos.211926
Language of fungi derived from their electrical spiking activity
Andrew Adamatzky
Published:06 April 2022https://doi.org/10.1098/rsos.211926
Review history
Abstract
Fungi exhibit oscillations of extracellular electrical potential recorded via differential electrodes inserted into a substrate colonized by mycelium or directly into sporocarps. We analysed electrical activity of ghost fungi (Omphalotus nidiformis), Enoki fungi (Flammulina velutipes), split gill fungi (Schizophyllum commune) and caterpillar fungi (Cordyceps militaris). The spiking characteristics are species specific: a spike duration varies from 1 to 21 h and an amplitude from 0.03 to 2.1 mV. We found that spikes are often clustered into trains. Assuming that spikes of electrical activity are used by fungi to communicate and process information in mycelium networks, we group spikes into words and provide a linguistic and information complexity analysis of the fungal spiking activity. We demonstrate that distributions of fungal word lengths match that of human languages. We also construct algorithmic and Liz-Zempel complexity hierarchies of fungal sentences and show that species S. commune generate the most complex sentences.
1. Introduction
Spikes of electrical potential are typically considered to be key attributes of neurons, and neuronal spiking activity is interpreted as a language of a nervous system [1–3]. However, almost all creatures without nervous system produce spikes of electrical potential—Protozoa [4–6], Hydrozoa [7], slime moulds [8,9] and plants [10–12]. Fungi also exhibit trains of action-potential-like spikes, detectable by intracellular and extracellular recordings [13–15]. In experiments with recording of electrical potential of oyster fungi Pleurotus djamor, we discovered two types of spiking activity: high-frequency (period 2.6 min) and low-frequency (period 14 min) [13]. While studying another species of fungus, Ganoderma resinaceum, we found that the most common width of an electrical potential spike is 5–8 min [16]. In both species of fungi, we observed bursts of spiking in the trains of the spike similar to that observed in the central nervous system [17,18]. While the similarity could be just phenomenological, this indicates a possibility that mycelium networks transform information via interaction of spikes and trains of spikes in manner homologous to neurons. First evidence has been obtained that indeed fungi respond to mechanical, chemical and optical stimulation by changing pattern of its electrically activity and, in many cases, modifying characteristics of their spike trains [19,20]. There is also evidence of electrical current participation in the interactions between mycelium and plant roots during formation of mycorrhiza [21]. In [22], we compared complexity measures of the fungal spiking train and sample text in European languages and found that the ‘fungal language’ exceeds the European languages in morphological complexity.
In our venture to decode the language of fungi, we first uncover if all species of fungi exhibit similar characteristics of electrical spiking activity. Then we characterize the proposed language of fungi by distributions of word length and complexity of sentences.
There is an emerging body of studies on language of creatures without a nervous system and invertebrates. Biocommunication in ciliates [23] include intracellular signalling, chemotaxis as expression of communication, signals for vesicle trafficking, hormonal communication and pheromones. Plants communication processes are seen as primarily sign-mediated interactions and not simply an exchange of information [24,25]. Evidences of different kinds of chemical ‘words’ in plants are discussed in [26,27]. Moreover, a modified conception of language of plants is considered to be a pathway towards ‘the de-objectification of plants and the recognition of their subjectivity and inherent worth and dignity’ [28]. A field of the language of insects has been developed by Karl von Frisch and resulted in his Nobel Prize for detection and investigation of bee languages and dialects [29,30]. An issue of the language of ants, and how species hosted by ants can communicate the ants language, was firstly promoted in 1971 [31]. In the early 1980s, analysis of the ants’ language using information theory approaches was proposed [32]. The approach largely succeeded in analysis of ants’ cognitive capacities [33–36].
We recorded and analysed, as detailed in §2, electrical activity of ghost fungi (Omphalotus nidiformis), Enoki fungi (Flammulina velutipes), split gill fungi (Schizophyllum commune) and caterpillar fungi (Cordyceps militaris). The phenomenological characteristic of the spiking behaviour discovered are presented in §3. Linguistic analysis and information and algorithmic complexity estimates of the spiking patterns are given in §4.
