Synaptic plasticity includes elements of a stochastic process and elements of an orderly process.

Synaptic plasticity includes elements of a stochastic process and elements of an orderly process.

I agree to Vladimir. What affects this more is as far as I know impossible to say by now.

Thanks for support.

Beautiful question...

However I agree that it is difficult to establish which (pre or post) synaptic plasticity is more important. If both exist, both have to be important. In this context there are several forms of plasticity including those that are expresed purely in the presynapse (interesting review: Yang Y and Calakos N (2013) Presynaptic long-term plasticity. Front. Synaptic Neurosci.), postsynaptically or on both sides of the synapse, by linking pre and postsynaptic plasticity via retrograde messengers (e.g. Cerebellar-LTD induced presynaptically, expressed postsynaptically).

Regarding the stochastic nature of the plasticity, I think that you could talk about a stochastic process just considering the fact of synapse establishment/strengthening (from my point of view is more like coincidence) but at the end of the process I think there is always an input that determines which synaptic connections are going to be potentiated/depressed. What I mean is that synaptic rearrangement is always adaptative to environmental (well, afferent) fluctuations, so, from my point of view, the global process is not stochastic.

Cheers

The response contains a contradiction. Mentioned chaotic processes and their strict organization. It captures the essence of plasticity.

If you talk about something "stochastic" you might be assuming that still exist some probability in this process to happen in a given timeline, so in some way you can predict this.

I guess that your question refers to something that could be random or not random and by this I mean a process where beside all the variables that you can control, it could happen or not without the chance of make a mathematical prediction.

Cheers

Thanks to all contributors. But my thought was little simpler. Its like the simplest example, if there is a Que in which number of persons at a given time depends upon both persons leaving the Que as well as persons adding to it. Then whats more important, taking pre and post synaptic plasticity comparable to persons leaving and adding to the que?

Any thought makes look at familiar from a different perspective.

Given the example, I still think that both are equally important... In fact both are necessarily equally important for the overall process.

A nice paper regarding this ( Wang DJ, Su LD, Wang YN, Yang D, Sun CL, Zhou L, Wang XX, Shen Y. Long-term potentiation at cerebellar parallel fiber-purkinje cell synapses requires presynaptic and postsynaptic signaling cascades. J Neurosci. 2014 Feb 5;34(6):2355-64)

you should go to a biochimical level (not my field). there is a variety of neurotransmitters (http://en.wikipedia.org/wiki/Synaptic_plasticity).

The plasticity depends on a variety of factors, and those unaccounted for make the process "stochastic". I guess the variability regards booth pre- and post-synaptic side.

Here I share an article that explain why is not easy to find patterns: http://journal.frontiersin.org/Journal/10.3389/fnsyn.2014.00003/full

Thank you J. Ramirez Franco for the article, really good and thanks to all contributors because it is a very interesting debate.

Very interesting, too, is the role of the astroglia (astrocytes), which are rarely considered, but have an important role to the structuring of the neurotransmitter propagation. sample review: http://www.hindawi.com/journals/np/2013/185463/

Synaptic plasticity is inherently stochastic in nature ... but I would not model it as a single stochastic process but as a joint probability of sorts taking into account presynaptic and postsynaptic changes. In such a case I would expect no side (pre or post) to be the preferred major contributor to change ... The site of maximal change will have to depend on the current molecular state of the system and the stimulation. I hope this is of use.

Does anyone of you know a publication which presents a mathematical model of the process? In theory I could imagine a data driven structure equation model which you could extend to predict likelihood of synaptogenesis given specific input parameters, but I am neither a statistician nor expert in physiology.

I think You can begin with a review suggested by Alma Dzib Goodin http://journal.frontiersin.org/Journal/10.3389/fnsyn.2014.00003/full

and for physiological approach I think a review by Yang and Calakos titled Presynaptic Long Term Plasticity will help you to begin with.

Hope this helps

Hi all,

concerning "modeling + biophysical models + LTP/LTD" I would to pin-point the following:

Migliore M, Lansky P. Biol Cybern. 1999 Oct;81(4):291-8. Computational model of the effects of stochastic conditioning on the induction of long-term potentiation and depression.

Dear Satya! I believe that you have your own opinion formed on the basis of advices many scientists. Good luck in the knowledge of synaptic and brain plasticity.

Thank you so much for your concern and interest, Sir. I am now working more and more on statistical approaches and most probability based modelling. Although, I am very new to the field and you can take me as curiosity driven stranger, but Your as well as other contributors' inputs really made this discussion very productive. Thank you so much. I hope others also getting involved. Science is all about inclusion.

Although most biological systems can accommodate a degree of stochasticity, synaptic plasticity, at least in the CA1 region of the hippocampus, seems to be very deterministic.

You may find this helpful:

https://www.researchgate.net/publication/50194883_Synaptic_plasticity_a_unifying_model_to_address_some_persisting_questions?ev=prf_pub

Article Synaptic Plasticity: A Unifying Model to Address Some Persis...