Search found 6387 matches

by ted
Fri May 23, 2025 5:36 pm
Forum: Other questions
Topic: tACS
Replies: 1
Views: 17

Re: tACS

I will assume that you are using the code in https://www.neuron.yale.edu/ftp/ted/neuron/extracellular_stim_and_rec.zip . The amplitude and time course of the extracellular stimulus is calculated by the procedure stim_waveform() in the file stim.hoc. The functionality of that procedure is very limite...
by ted
Fri May 23, 2025 1:50 pm
Forum: NEURON hacks
Topic: AlphaSynapse dynamics
Replies: 1
Views: 45

Re: AlphaSynapse dynamics

Hello NEURON community: This post talks about the underlying equation of AlphaSynapse. https://www.sas.upenn.edu/LabManuals/BBB251/NIA/NEUROLAB/HELP/alphasyn.htm I am wondering if the "v", postsynaptic voltage, is constant (and set as resting voltage) or should change during current injec...
by ted
Tue May 13, 2025 11:49 am
Forum: Modeling networks
Topic: Simulation fails when adding 3D location to cell
Replies: 1
Views: 1230

Re: Simulation fails when adding 3D location to cell

I seem to have misplaced my scrying stone, and without that it is difficult to diagnose the unseen. Perhaps you could share what you mean by "add the 3D location" e.g. by providing code examples of what you did that worked, and what you did that didn't work.
by ted
Mon May 12, 2025 1:30 pm
Forum: NEURON + Python
Topic: Changing parameters in NMODL files from within a Python script?
Replies: 2
Views: 32489

Re: Changing parameters in NMODL files from within a Python script?

Good Python suggestion, urid. Here are some NEURON-specific comments: First, just to make sure that everyone who reads this thread knows what we're writing about-- 1. NMODL's global variables. An NMODL-specified mechanism's PARAMETERs are global by default (have the same value in all segments in whi...
by ted
Sun Apr 27, 2025 3:01 pm
Forum: UNIX/Linux
Topic: Windows 7.2 NEURON on Linux?
Replies: 3
Views: 11047

Re: Windows 7.2 NEURON on Linux?

You're quite welcome, Shaina. Glad to help!
by ted
Tue Mar 25, 2025 7:35 pm
Forum: Modeling networks
Topic: Adding extracellular stimulus to network of neurons
Replies: 9
Views: 49962

Re: Adding extracellular stimulus to network of neurons

I've never seen this msg signify a discontinuity. It's usually caused by NMODL code with rate constants that involve exponential functions. Typically the exp is in a denominator where limiting the value returned by exp(x) to exp(700) will do no harm. Nothing will blow up numerically, and your simula...
by ted
Tue Mar 25, 2025 7:30 pm
Forum: UNIX/Linux
Topic: Windows 7.2 NEURON on Linux?
Replies: 3
Views: 11047

Re: Windows 7.2 NEURON on Linux?

Hi, Shaina. Sorry about the delay, but I've been traveling a bit after the course we did at ASU week before last. Open a terminal and cd into the the folder that holds your code. If there is a file called nrnmech.dll, delete it. Or if you see a folder called x86_64, delete that and all its contents....
by ted
Thu Mar 13, 2025 1:24 am
Forum: Other questions
Topic: How is point process current added into the equation solved by NEURON
Replies: 2
Views: 21241

Re: How is point process current added into the equation solved by NEURON

The ODE for each segment is of the form transmembrane capacitive current + transmembrane ionic current = sum of all currents arriving in the segment from adjacent segments + sum of all currents that enter the segment from all point processes that generate currents Notice that current in these equati...
by ted
Tue Feb 25, 2025 8:43 am
Forum: NEURON + Python
Topic: Coreneuron CPU and multisplit
Replies: 1
Views: 12229

Re: Coreneuron CPU and multisplit

The primary utility of multisplit is to achieve load balance in network simulations, and that is useful only when the network contains a very few model cells that are very large. Otherwise the performance boost will not be worth the programmer's effort required to restructure your model. Few single ...
by ted
Wed Feb 19, 2025 2:42 pm
Forum: Other questions
Topic: Factors Influencing NEURON Simulation Run Time Beyond Total Compartment Count?
Replies: 1
Views: 14149

Re: Factors Influencing NEURON Simulation Run Time Beyond Total Compartment Count?

Runtime depends on model complexity. A crude but effective measure of complexity is the total number of ODEs. For every segment there is one ODE for the cable equation, plus one ODE for each state variable of every mechanism associated with that segment that requires numerical integration. This incl...
by ted
Wed Feb 19, 2025 2:15 pm
Forum: Other questions
Topic: error
Replies: 1
Views: 13090

Re: error

About this Forum: If you need to paste code, be sure to surround it with the proper markup (that's what the < / > formatting button is for). Otherwise things like leftsquarebracket i rightsquarebracket will be treated as formatting instructions (interpreted as "italic"). Here's how to fix ...
by ted
Mon Feb 17, 2025 10:11 am
Forum: Modeling networks
Topic: Adding extracellular stimulus to network of neurons
Replies: 9
Views: 49962

Re: Adding extracellular stimulus to network of neurons

I asked because DBS protocols use biphasic, charge-balanced waveforms. Vector play works for arbitrary waveforms. If the conductive medium is nondispersive ("purely resistive"), then the time course of extracelluar potential vx(x,y,z) will be of the form A(x,y,z)*f(t) where f is a function...
by ted
Fri Feb 14, 2025 12:00 am
Forum: Modeling networks
Topic: Adding extracellular stimulus to network of neurons
Replies: 9
Views: 49962

Re: Adding extracellular stimulus to network of neurons

Haven't been much help yet--you've done all the work so far. Implementing stimulation will be easy if you only need a single rectangular pulse--the IClamp class will do for that. But what if your stimulus current should have a more complex time course, e.g. two or more monophasic rectangular pulses,...
by ted
Thu Feb 06, 2025 12:58 pm
Forum: NEURON + Python
Topic: kernel dying in unusual circumstances
Replies: 1
Views: 17627

Re: kernel dying in unusual circumstances

To provide specific advice, I will have to know what you're trying to do. All that is clear from the example code is that 1. it assumes that soma2 and dend2 have the same nseg value. This is unlikely to be true. 2. it assumes that this nseg value changes on every pass through the "for seg in se...
by ted
Wed Feb 05, 2025 5:35 pm
Forum: Adding new mechanisms and functions to NEURON
Topic: Boltzmann and elementary charge values
Replies: 6
Views: 46847

Re: Boltzmann and elementary charge values

To give specific advice, I'll have to reproduce the error for myself. Can you email the mod file in question to ted dot carnevale at yale dot edu?