Abstract

From the time of Cajal, histologists, have attempted to understand how neurons encode memory. Cajal identified synaptic connections between neurons which Hebb conceptualized as “synaptic plasticity”, processes related to recall. But aside from synaptic connectivity, they did not consider the “meaning” of the neuron’s extended shape.

The neuron has a very large surface area with branching dendrites exposing surface spines that permit intimate exposure to the surroundings. Golgi perceived a perineural net (PNN) around the neuron, which Cajal dismissed as a “staining artifact”. Subsequent work established the presence of a web of glycosamino-glycans and proteins around the neurons, termed extracellular matrix (nECM).

Recognizing that neural morphology and its interactions with its surroundings have functional relevance, we have proposed a tripartite mechanism of neural memory. It involves the chemical encoding of cognitive units of information (cuin fo), based on the interactions of three physiologic compartments, namely: 

• Neurons – cells with large surface area, extended arborized shape with many dendrites.
• Extracellular matrix (nECM)- a static hydrogel, surrounding neurons.
• Dopants (trace metal cations and neurotransmitters (NTs)) – diffusible molecules which form metal-centered complexes within the nECM. The NTs are the molecular correlates of emotive states.

Thus, the nECM is not irrelevant but critical to the functioning of the arborized neuron. In conjunction with morphologic considerations, the tripartite mechanism permits one to construct a physiologically credible account for the encoding of neural memory. 

Keywords: Neural Shape; Dendrites; Neurotransmitters; Neural Code; Trace Metals

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Citation

Citation: Chaim Gilon. “Interpreting Neural Morphology". Relationship Between Both Values”. Acta Scientific Neurology 3.3 (2020): 05-08.

Copyright

Copyright: © 2020 Chaim Gilon. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.