Neurobiology: consciousness and intelligence revealed in plants

Plant Intelligence, Neurobiology and Consciousnessneurobiology plant consciousness intelligence secret life

John McKenna, writing in The Irish Times, says, “A video [of Prof Mancuso’s work] and an article in The New Yorker about bean plants entitled ‘The intelligent plant’ made my mind boggle.” Having read the article and seen the video in the New Yorker, my mind boggled also! It revealed that living organisms (I include elements as they contain a reactivity unique to life) carry something more than just the physical. In the first video below you can see that pea plants have some form of knowledge, perceptivity which genes alone cannot explain. After all, dead pea plants contain the same genes as when they were living but can’t do what these living plants do, so living entities have something extra, beyond the physical. They’ve a metaphysical quality that informs their existence. This metaphysical quality is a self-preserving quality. (Watch the video here: Do Bean Plants Show Intelligence?)

A few quotes from the accompanying article by Michael Pollan below are worth commenting on,

… in a controversial 2006 article in Trends in Plant Science proposing a new field of inquiry that the authors, perhaps somewhat recklessly, elected to call “plant neurobiology.” The six authors—among them Eric D. Brenner, an American plant molecular biologist; Stefano Mancuso, an Italian plant physiologist; František Baluška, a Slovak cell biologist; and Elizabeth Van Volkenburgh, an American plant biologist—argued that the sophisticated behaviors observed in plants cannot at present be completely explained by familiar genetic and biochemical mechanisms…

They would challenge contemporary biology’s reductive focus on cells and genes and return our attention to the organism and its behavior in the environment…

In a recent experiment, Heidi Appel, a chemical ecologist at the University of Missouri, found that, when she played a recording of a caterpillar chomping a leaf for a plant that hadn’t been touched, the sound primed the plant’s genetic machinery to produce defense chemicals. Another experiment, done in Mancuso’s lab and not yet published, found that plant roots would seek out a buried pipe through which water was flowing even if the exterior of the pipe was dry, which suggested that plants somehow “hear” the sound of flowing water.

Gagliano reported that she retested her plants after a week and found that they continued to disregard the drop stimulus, indicating that they “remembered” what they had learned. Even after twenty-eight days, the lesson had not been forgotten. She reminded her colleagues that, in similar experiments with bees, the insects forgot what they had learned after just forty-eight hours. Gagliano concluded by suggesting that “brains and neurons are a sophisticated solution but not a necessary requirement for learning,” and that there is “some unifying mechanism across living systems that can process information and learn.”

While talking with Mancuso, I kept thinking about words like “will,” “choice,” and “intention,” which he seemed to attribute to plants rather casually, almost as if they were acting consciously. At one point, he told me about the dodder vine, Cuscuta europaea, a parasitic white vine that winds itself around the stalk of another plant and sucks nourishment from it. A dodder vine will “choose” among several potential hosts, assessing, by scent, which offers the best potential nourishment. Having selected a target, the vine then performs a kind of cost-benefit calculation before deciding exactly how many coils it should invest—the more nutrients in the victim, the more coils it deploys. I asked Mancuso whether he was being literal or metaphorical in attributing intention to plants.

Perhaps the most troublesome and troubling word of all in thinking about plants is “consciousness.” If consciousness is defined as inward awareness of oneself experiencing reality—“the feeling of what happens,” in the words of the neuroscientist Antonio Damasio—then we can (probably) safely conclude that plants don’t possess it. But if we define the term simply as the state of being awake and aware of one’s environment—“online,” as the neuroscientists say—then plants may qualify as conscious beings, at least according to Mancuso and Baluška. “The bean knows exactly what is in the environment around it,” Mancuso said. “We don’t know how. But this is one of the features of consciousness: You know your position in the world. A stone does not.”

The ideas of neurobiology are controversial but meet with venom from many biologists who are not at all open. In his interview with Marcuso, Vikas Shah, in Thought Economics, January 2011, says:

Everywhere we look, in the ways that plants react to problems, we can see actions that are not just automatic responses. Every plant has to endlessly sense and monitor a number of environmental parameters; and is constantly called upon to make decisions. This is not the place to list numerous cases of intelligence behaviour in plants, a huge volume of such examples can be found in scientific literature and, anyone who has spent only a few hours observing how plants react to environmental changes will have a clear idea about their acute senses and prompt responses.

Vikas Shah says of biologist Anthony Trewavas, who expands on this thinking, in his paper “Aspects of Plant Intelligence” (Published in the Annals of Botany 92: 1‐20, 2003):

His views highlight one of the most important flaws in our scientific technique‐ that being our philosophy of reductionism‐ where science tries to understand the nature of complex things by reducing and averaging rather than understanding the phenomenon as a whole.

Life and what it possesses might never fit in with a scientific materialist and reductivist mindset and least of all be seen as a law. We will remain at a loss without a working definition of Life, not made easy by the many issues, as Shah continues:

Even defining life itself suffers from scientific and philosophical debate. Ruiz‐Mirazo et. al in a 2004 paper entitled “A Universal Definition of Life” state, “Definitions of life are highly controversial. And it is not just a question of lack of consensus among the different proposals formulated so far. Some authors are very sceptical about the actual possibility of grasping ‘in any scientifically relevant language’ such a complex and multifarious phenomenon. Others think that we have to wait until biological theory(ies) become more rigorous, more encompassing and meaningful. And some others consider that it is not worth undertaking the challenge since, even if we could obtain a proper definition of life, it would still be a rather conventional one and would probably have little influence on the development of specific research programs in biology. The living phenomenology shows, indeed, many different sides (that appear at various levels of organization) and it is not easy to capture all of them in a single conceptual scheme. This is made even more difficult by life’s ability to diversify and explore its own limits (always producing border‐line cases, exceptions to the rule, …). Last century’s impressive advances in molecular biology have revealed a great underlying biochemical unity of all living forms, but it is not clear to what extent this is the result of contingency or of real necessity: i.e., whether that unity can serve to extract general biological principles or just derives from having a universal common ancestor of all terrestrial life. In addition, since the problem of the origin of life is also far from being solved, it is not at all obvious how those ‘biological principles’ would relate to the general laws of physics and chemistry, i.e., if they would be subject to an eventual reduction to the latter, or should have their own ‘status’ (with their own explanatory power, degree of abstraction, etc.) as scientific laws.”

The need for a holistic approach to biology is still a long way off if Agutter and Wheatley are correct in their book (see below; pages 104ff). They say that in this current “third anti-materialist stance” differences between “living and non-living matter” (can’t get away from “matter” even when describing non-matter!) are described in physical terms: living consist mostly of carbon, hydrogen, nitrogen and oxygen while non-living like clay consist mostly of silicon and aluminium; living molecules are bigger and more complicated and finally, biological molecules have very specific shapes. The authors do acknowledge that these differences are insufficient to show a radical distinction between living and non-living, as vitalism would require. Wondering if Aristotle would accept this distinction and if it would satisfy Aristotle’s entelechy, (Entelechy; in philosophy, the realization of potential; the supposed vital principle that guides the development and functioning of an organism or other system or organization: such self-organization required a special biological force—entelechy. C.f. Oxford Dictionary online.), they suggest he would have accepted that entelechy resides not in matter itself but in the way in which matter is organised. To me, this subordinates the vital living principle to matter and so is not satisfactory since what is matter without life/energy?

But is there a difference between the energy in non-living matter, like the elements, which have an ability to react, and the energy in the living? Prof Brian Cox presented a tv show last year in which he set out to reveal what energy is. He didn’t. All he did was show how energy moves. He still couldn’t show it, explain why we have it or from where it originated, just like a builder may show us the effects of a leak on my ceiling but not show where it originated or why it originated, he only shows us what is on the surface.

As I write, a professor emeritus of psychology at Trinity College, Dublin responds in a letter to the The Irish Times to a neuroscientist who suggests mind is dependent upon the physical brain. Prof Greene takes issue with this stance and explains there is more to mind than the brain. Her comments are worth considering:

Sir, – With reference to Joe Humphreys’s column (Arts & Ideas, January 10th) on the unthinkable great idea that “the mind arises solely from the activity of the brain”, may I suggest this “great” idea is “unthinkable” because it is wrong.

Dr Kevin Mitchell, the interviewee who promotes this great idea, suffers from the narrow vision that seems typical of many brain scientists.

He reminds me of the unfortunate scientist, Dr Hfuhruhurr, played by Steve Martin in the film The Man with Two Brains, who falls in love with a female brain kept “alive” in a jar. The film is labelled as a science fiction comedy, for of course we all appreciate that a brain cannot function in isolation from a living body. Yet Dr Mitchell says “mental states arise from brain states” and that “we don’t actually need anything else in our overall theory of how they emerge except brain states”.

He cites the reality that when the brain dies or is damaged the mind dies or is damaged. This is incontrovertible, but what it tells us is that the brain is necessary to the functioning of the mind, or the processes we call the mind. The brain is necessary but it is not sufficient, many more factors come into play. The mind, and its qualities such as the sense of self and consciousness, emerges from complex interactions of the brain with the body, the material world and the socio-cultural world of relationships and meanings.

Until neuroscientists such as Dr Mitchell realise this and broaden their perspective they will make no progress whatsoever in understanding the mind and they will soon come to a full stop in their understanding of the brain. Much remains to be discovered. The alternative to Dr Mitchell’s brand of neuroscience is not religion or poetry, as the article suggests, but better science. – Yours, etc,

Sheila Greene,
Professor Emeritus,
School of Psychology,
Trinity College,
Dublin 2

In the same vein, Prof Willie Reville, writing his regular column in The Irish Times, explains the problem regarding scientism, materialistic philosophy and the supernatural as follows,

It is reasonable to be a materialist. But, since materialism is unproven, materialists must accept that, no matter how improbable it seems to them, there is a possibility they might be wrong and a supernatural dimension might exist. Materialists are therefore obliged to respect the position of religious people who believe in the supernatural but accept all that science has and will discover. Of course, religious people have an equivalent obligation towards materialists.

So the materialists are in a glasshouse throwing stones. Another author, philosopher Gareth Southwell in his book 50 Philosophy of Science Ideas You Really Need to Know is one of the few philosophers to discuss vitalism. Although he says vitalism has religious origins it doesn’t have to be dependent upon a religious mindset. He says Darwin’s theory of evolution is mechanistic but surely not when, for natural selection to take place, a dynamism is required for an organism to react to its environment. This action and reaction to a situation is dependent upon dynamism and therefore vitalism. Southwell doesn’t appreciate this but what I do accept of his commentary is his response to philosophers like Daniel Dennett in his book Kinds of Minds when Dennett claims naively that, “Vitalism has been relegated to the trash heap of history – unless you are prepared to declare that the world is flat.” By whom? I ask because the main author on vitalism was Hans Driesch who concluded that vitalism has never been disproved, it just went out of fashion. That may have been a century ago but as Southwell concludes, “The debate goes on, albeit in a one-sided way, but the continuing enigma of consciousness, for instance, which Dennett himself struggles with, suggests that the traditional scientific view still arguably fails to account for the very things that vitalism claims to explain: how material things can have purpose, consciousness and sentience (pp.88-91).

“Dynamic” is fundamental to biology, the natural sciences, medicine and philosophy because it is only found in the living, vital entities (including elements which have an inbuilt template to react in each element’s individual way). It is in this vitality/vital force that our identity is found, not only in the genetic matter. A dead body is not a person as is a living person (as long as there is life/vital force there is the uniqueness of that organism, bound up in their consciousness – hence an argument against abortion since consciousness is there at conception). In homeopathy we see our patients suffering from “incurable genetic diseases” improve because disease is not physical but a vital dynamic reaction as Hahnemann showed in his Organon. There is more to us than genes.

By the process of dilution and succusion, which Hahnemann discovered (and Koch and Pasteur copied to make their vaccines), homeopathic medicines liberate that unique consciousness of each vital substance and the blueprint, the template of that vital matter is attenuated and stored in our medicines. This is how, even “inert” elements like vegetable carbon (charcoal) and inert plants like Lycopodium, using this liberated metaphysical blueprint/template of that substance, can act with great dynamism.

It is in theory and practise that Hahnemann has shown that each has a unique identity contained in their consciousness and is part of one whole constitution, rather than splitting the vital and physical into a duality, since that vital force pervades every cell. And when that vital force is in me and every part of me, how can I say I am different from my body? that my big toe is different from my shoulder?

Does it matter which comes first, matter or vital life force/consciousness? It’s a chicken and egg.

References and bibliography 
1. The New Yorker article “The Intelligent Plant” by Michael Pollan is available here

2. Another video by Prof Stefano Mancuso, his Ted talk is available at his LINV website here

3. An interview titled “Our Understanding of Life” with Prof Mancuso is available here 

4. Thinking about Life: The History and Philosophy of Biology and Other Sciences by Paul Agutter and Denys N. Wheatley.

5. 50 Philosophy of  Science Ideas You Really Need to Know  by Gareth Southwell.

6. The Theory and History of Vitalism by Hans Driesch. 

7. Organon of Medicine by Samuel Hahnemann.

8. The Secret Life of Plants by Tompkins and Bird

Further Information
The difference between plants and animal kingdoms – a wonderful article by Prof Reville in The Irish Times

Do animals have consciousness? How do swarms know where to move and when? Watch this video Then watch this

The Magic of Consciousness; Royal Institution video with Prof Nicholas Humphrey

New book: What the Great Philosophers Say About Consciousness

Consciousness survives death according to scientific study at Southampton University: First hint of ‘life after death’ in biggest ever scientific study

We are finally waking up to the secret life of trees, says Richard Mabey in the

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