The Electrome of a Parasitic Plant in a Putative State of Attention Increases the Energy of Low Band Frequency Waves: A Comparative Study with Neural Systems.

Selective attention is an important cognitive phenomenon that allows organisms to flexibly engage with certain environmental cues or activities while ignoring others, permitting optimal behaviour. It has been proposed that selective attention can be present in many different animal species and, more recently, in plants. The phenomenon of attention in plants would be reflected in its electrophysiological activity, possibly being observable through electrophytographic (EPG) techniques. Former EPG time series obtained from the parasitic plant Cuscuta racemosa in a putative state of attention towards two different potential hosts, the suitable bean (Phaseolus vulgaris) and the unsuitable wheat (Triticum aestivum), were revisited. Here, we investigated the potential existence of different band frequencies (including low, delta, theta, mu, alpha, beta, and gamma waves) using a protocol adapted from neuroscientific research. Average band power (ABP) was used to analyse the energy distribution of each band frequency in the EPG signals, and time dispersion analysis of features (TDAF) was used to explore the variations in the energy of each band. Our findings indicated that most band waves were centred in the lower frequencies. We also observed that C. racemosa invested more energy in these low-frequency waves when suitable hosts were present. However, we also noted peaks of energy investment in all the band frequencies, which may be linked to extremely low oscillatory electrical signals in the entire tissue. Overall, the presence of suitable hosts induced a higher energy power, which supports the hypothesis of attention in plants. We further discuss and compare our results with generic neural systems.

Plants as electromic plastic interfaces: A mesological approach.

In this manuscript, we propose that plants are eco-plastic and electromic interfaces that can drive emergent intelligent behaviours from synchronized electrical networks. Behind the semantic and anthropocentric problems related by many authors to the extensive use of the terms cognition, intelligence or even 'consciousness' for plants, we suggest a more pragmatic perspective, considering the vegetal world to be a complex biosystemic entity that is able to co-build the world or a form of the world or of significant reality via a set of reciprocal, emerging and confluent interactions. Speaking of adaptive sensory modalities involving perceptual binding or a global state of receptivity nonlinearly leading to cognitive functions, learning capabilities and intelligent behaviours of plants seem to be the more realistic and operational model to describe how plants perceive and treat environmental data. In this study, we strongly suggest that the electrome, which mainly involves constant spontaneous emission of low voltage potentials, is an early marker and a unifying factor of whole plant reactivity in a constantly changing environment and is therefore the key to understanding the cognitive nature of plants. This dynamic coupling enables plants to be knowledge-accumulating systems that are used by evolution to progress and survive, while mesological plasticity is a unique means for plants to interact as subjects with their milieu (umwelt) or natural habitat and to co-signify a possible world.

Dynamic protoneural networks in plants: a new approach of spontaneous extracellular potential variations.

Taking as a basis of discussion Kalanchoe's spontaneous and evoked extracellular activities recorded at the whole plant level, we put the challenging questions: do these low-voltage variations, together with endocellular events, reflect integrative properties and complex behavior in plants? Does it reflect common perceptive systems in animal and plant species? Is the ability of plants to treat short-term variations and information transfer without nervous system relevant? Is a protoneural construction of the world by lower organisms possible? More generally, the aim of this paper is to reevaluate the probably underestimated role of plant surface potentials in the plant relation life, carefully comparing the biogenesis of both animal and plant organisms in the era of plant neurobiology. Knowing that surface potentials participate at least to morphogenesis, cell to cell coupling, long distance transmission and transduction of stimuli, some hypothesis are given indicating that plants have to be studied as environmental biosensors and non linear dynamic systems able to detect transitional states between perception and response to stimuli. This study is conducted in the frame of the "plasticity paradigm," which gives a theoretical model of evolutionary processes and suggests some hypothesis about the nature of complexity, information and behavior.

9-Carboxymethyl-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazin-4-one-2-carbocylic acid (RPR117824): selective anticonvulsive and neuroprotective AMPA antagonist.

Excessive release of glutamate, a potent excitatory neurotransmitter, is thought to play an important role in a variety of acute and chronic neurological disorders, suggesting that excitatory amino acid antagonists may have broad therapeutic potential in neurology. Here, we describe the synthesis, pharmacological properties and neuroprotective activity of 9-carboxymethyl-imidazo-[1-2a]indeno[1-2e]pyrazin-4-one-2-carboxylic acid (RPR117824), an original selective AMPA antagonist. RPR117824 can be obtained through a six-step synthesis starting from (1-oxo-indan-4-yl) acetic acid, which has been validated on a gram-scale with an overall yield of 25%. Monosodium or disodium salts of the compound exhibit excellent solubility in saline (> or = 10 g/L), enabling intravenous administration. RPR117824 displays nanomolar affinity (IC(50)=18 nM) for AMPA receptors and competitive inhibition of electrophysiological responses mediated by AMPA receptors heterologously expressed in Xenopus oocytes (K(B)=5 nM) and native receptors in rat brain slices (IC(50)=0.36 microM). In in vivo testing, RPR117824 behaves as a powerful blocker of convulsions induced in mice or rats by supramaximal electroshock or chemoconvulsive agents such as pentylenetetrazole, bicuculline, isoniazide, strychnine, 4-aminopyridine and harmaline with half maximal effective doses ranging from 1.5 to 10 mg/kg following subcutaneous or intraperitoneal administration. In disease models in rats and gerbils, RPR117824 possesses significant neuroprotective activity in global and focal cerebral ischemia, and brain and spinal cord trauma.