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Journal of Integrative Neuroscience  2019, Vol. 18 Issue (2): 181-185    DOI: 10.31083/j.jin.2019.02.6101
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The tripartite mechanism as the basis for a biochemical memory engram
Gerard Marx1, Chaim Gilon2, *()
1 MX Biotech Ltd., Jerusalem 95744, Israel
2 Institute of Chemistry, Hebrew University, Jerusalem 91904, Israel
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In this paper, we address the enigma of the memory engram, the physical trace of memory in terms of its composition, processes, and location. A neurochemical approach assumes that neural processes hinge on the same terms used to describe the biochemical functioning of other biological tissues and organs. We define a biochemical process, a tripartite mechanism involving the interactions of neurons with their neural extracellular matrix, trace metals, and neurotransmitters as the basis of a biochemical memory engram. The latter inextricably link physiological responses, including sensations with affective states, such as emotions.

Key words:  Cognitive information      affective biochemistry      trace metals      neurotransmitters      extracellular matrix      memory engram      emotive memory     
Submitted:  11 January 2019      Accepted:  10 June 2019      Published:  30 June 2019     
*Corresponding Author(s):  Chaim Gilon     E-mail:

Cite this article: 

Gerard Marx, Chaim Gilon. The tripartite mechanism as the basis for a biochemical memory engram. Journal of Integrative Neuroscience, 2019, 18(2): 181-185.

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Table 1  Kinetics of various neural processes.
Process Time scale
Protein chain synthesis 10-1 sec per amino acid
RNA elongation 10-2 sec per base
DNA elongation 10-3 sec per base
Neural firing rate 10-2 sec
Neuro-electric impulse 1-100 m/sec
Neural GPCR receptor diffusion 10-1 to 10-3 μm2 sec-1
Ca+2 diffusion in nECM 2.3 × 10-6 cm2/s
Molecular binding events 10-7 sec
Protein turnover (replacement) 3 months
Mosaic diffusion over neural surface 10-1 to 10-3 μm2/sec
Ionic memory chip byte encoding 10-7 sec
Figure 1.  Chemo-graphic representations of the reaction of an nECM binding site for a metal cation, an "address". The binding of a NTs to the metal-centered cuinfo confers an emotive context (Adapted from Marx and Gilon, 2016).

Figure 2.  The neuron is surrounded by nECM(GAG lattice not shown) which serves as a neurochemical "library" wherein units of encoded memories are stored as cuinfo. The colored boxes representing the individual cuinfo described in Figure1, arenottoscale, astheyareof molecular dimension (i.e. 10 nm) compared to the 10-100 μm scale of the neuron and its parts. The different colors indicate complexes with different combinations of NTs and metal cations.

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