Extracting Network Connectivity for Artificial Cells

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tseredynski

Extracting Network Connectivity for Artificial Cells

Post by tseredynski »

I have a question very similar to that covered in the topic "Extracting Network Connectivity." Your final solution to plot the pre-cell information for a poison cell was the following:
ted wrote:My mistake. The first line of the definition of myprecell() was supposed to be
obfunc myprecell() { localobj nil

If your code works with
obfunc myprecell() {
i.e. after deleting the declaration that nil is a localobj,
then there must have been a
localobj nil
statement somewhere else in your code at the top level, i.e. outside of any object.

For future readers of this thread: the corrected procedure is

Code: Select all

// argument is a NetCon
obfunc myprecell() { local nil
  // nil points to NULLobject
  if ($o1.precell() == nil) {
    return $o1.pre()
  } else {
    return $o1.precell()
  }
}
My question regards getting similar information from integrate-and-fire cells. From what I've read in the other topic it sounds like there was a variable defined in the cell class called "pre." I browsed the intfire1.mod file and cannot find any reference to such a variable. Is it possible to extract pre-cell data from netcons involving intfire cells? If so, where can I look in the future to find out such things on my own, and by what means can I get this data?

Thank you.
ted
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Re: Extracting Network Connectivity for Artificial Cells

Post by ted »

First place I look for this kind of information is in the documentation of the NetCon class. NetCon.pre() and NetCon.precell() report the presynaptic cell, NetCon.syn() and NetCon.postcell() report the target cell. Given a List that contains all the NetCons in a model, one can iterate over all elements of that list and use these basic functions to discover the network architecture. Also useful are precell(), precelllist(), postcell, postcelllist(), synlist(), preloc(), and postloc(). Finally, if one has a cell (synaptic mechanism) but doesn't know what NetCons use the cell (synapse) as a source (target), one can always attach a new NetCon to it and then use that NetCon as a "hook" for getting a List that contains the other NetCons for which it is a source (target).
tseredynski

Re: Extracting Network Connectivity for Artificial Cells

Post by tseredynski »

Thank you. So what I've understood from the documentation is that pre and syn are used for artificial cells, and precell and postcell are meant for "real" cells?
ted
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Re: Extracting Network Connectivity for Artificial Cells

Post by ted »

Those methods can be used with any NetCon, regardless of the nature (or existence) of the spike source ("presynaptic element") or target ("postsynaptic element"). It's up to the programmer to write code that takes the proper action depending on the value returned by any of those methods.
tseredynski

Re: Extracting Network Connectivity for Artificial Cells

Post by tseredynski »

Alright, thank you.
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