Search found 56 matches

by lb5999
Mon May 23, 2011 5:08 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Anomalous Spike in A-conductance
Replies: 3
Views: 2092

Anomalous Spike in A-conductance

Hi NEURON Forum, I am using a .mod file called borgka.mod, which is a model of the A-current membrane mechanism. This transient outward potassium current activates during the rising phase of an afterhyperpolarisation, and consequently prolonges the AHP.. delaying the return to resting potential/incr...
by lb5999
Wed May 18, 2011 6:21 am
Forum: Other questions
Topic: determining length of AHP for recorded membrane pot vector
Replies: 1
Views: 1463

determining length of AHP for recorded membrane pot vector

Hi NEURON forum, I have a dataset of 3 recorded vectors - vrec[0], vrec[1] and vrec[2] and a timestep vector vdt. The recorded vectors show the response of my cell to a brief depolarising pulse, causing a single action potential, and have been truncated using vrec.remove() to leave only the trough a...
by lb5999
Tue May 10, 2011 3:35 am
Forum: Other questions
Topic: Matrix of recorded vectors error; matrix .dat file truncated
Replies: 1
Views: 1328

Matrix of recorded vectors error; matrix .dat file truncated

Hi NEURON Forum, I have a matrix, which has first column which is the timestep, and last 3 columns which consist of the recordings from a simulation from 3 different sections of my cell. When I write the matrix to a data file, and open the .dat datafile for viewing (and opening in MATLAB), it trunca...
by lb5999
Tue Apr 19, 2011 4:14 am
Forum: Other questions
Topic: Determining and changing the resting membrane potential
Replies: 11
Views: 5757

Re: Determining and changing the resting membrane potential

He Ted, I did everything you said (apart from 5. - I am not sure at which stage to do this) and when I run init.hoc I only have one graph window for Graph[0]. I then run batchrun and it tells me: oc>batchrun(10, 100, -0.1, 0.02, 10) nrniv: Object ID doesn't exist: Graph[1] near line 144 batchrun(10,...
by lb5999
Sun Apr 10, 2011 3:57 pm
Forum: Other questions
Topic: Determining and changing the resting membrane potential
Replies: 11
Views: 5757

Re: Determining and changing the resting membrane potential

Hi, I would like to implement this piece of code to a model cell I have created in the hoc command prompt. I have a folder containing my own membrane mechanisms and some code which describes the build up of the cell. How would I apply this code to my cell? Would I simply move all the files into the ...
by lb5999
Thu Apr 07, 2011 4:09 pm
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

Yup you are right, the distribution I am picking from isn't ideal.. I'll change this!

Thanks for your pointers, I'll have a good think and stab at B & C and let you know how I get on,

lb5999
by lb5999
Thu Apr 07, 2011 5:14 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

So I found out that with && I could write the following piece of syntax which did what I wanted... objectref r r=new Random() r.norma(0,1) func rand() { x=r.repick() if (x<1.1 && x>0.9) {return x} else {return rand()} for i=0,20 print rand() Can you help me with the next phase please? This involves ...
by lb5999
Wed Mar 30, 2011 6:27 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

Hi Ted, Thanks for your message. I have attempted to truncate the desired returned values, to be assigned to the weight of the NetCon, with an upper and lower bound of 1 and -1 respectively (see below). These values aren't probably what I will go for, but presumably I can easily alter them at a late...
by lb5999
Tue Mar 29, 2011 12:49 pm
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

I think the membrane potential responds how I would expect in both the simple soma cell, and when this code is implemented on my model.. what do you think Ted?
by lb5999
Mon Mar 28, 2011 9:06 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

Also, I presume I write something like the following, to set the weight of the NetCon 'nc' to some randomly generated value (from a distibution I choose):

Code: Select all

proc setweight() {
nc.weight = rand()
}
Thanks,

Linford
by lb5999
Mon Mar 28, 2011 7:19 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

One more thing, don't worry about addressing my question regarding object references within func and proc commands; I already knew the following (again, I quote The NEURON Book: The objref keyword can appear within a compound statement, but the names must originally have been declared outside any fu...
by lb5999
Mon Mar 28, 2011 6:40 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

OK.. So I think I found something that paves the way to clearing up one of my problems. As is written in The NEURON Book (page 366, Chapter 13): As mention in Chapter 12, objref arguments are passed using call by reference. This has two consequences: the called func or proc can change which object t...
by lb5999
Mon Mar 28, 2011 6:24 am
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Re: Playing EPSPs into cell with random distribution of amp

Hi Ted, Thank you for your reply. I understand how you have tackled this problem, although I think I may need a few more hints. So far I have create soma insert hh insert pas objectvar ns, nc, syn ns = new NetStim(0.5) syn = new ExpSyn(0.5) nc = new NetCon(ns, syn, -40, 0, 0.5) tstop=1000 trainstart...
by lb5999
Sat Mar 26, 2011 4:56 pm
Forum: Adding new mechanisms and functions to NEURON
Topic: Playing EPSPs into cell with random distribution of amp
Replies: 14
Views: 4923

Playing EPSPs into cell with random distribution of amp

Hi NEURON Forum users,

I need to write a piece of code that plays into a cell a series of EPSP's that have fixed frequency and heights of random amplitude (distributed normally, say, around approximately 12mV positive to resting membrane potential). If anyone has any hints that would be great.

L
by lb5999
Fri Mar 25, 2011 6:03 am
Forum: Other questions
Topic: Displaying Injected current pulses from an IClamp
Replies: 2
Views: 1599

Re: Displaying Injected current pulses from an IClamp

Perfect! Thank you Ted.. I have another question, I'll post it as a new thread.

L