Search found 5654 matches

by ted
Wed Oct 30, 2019 11:04 am
Forum: Getting started
Topic: Spike configuration at internode sections of myelinated axon
Replies: 5
Views: 299

Re: Spike configuration at internode sections of myelinated axon

Enthusiasm is good, asking good questions is good, but this thread is quickly becoming an informal short course on cellular neurophysiology plus circuit theory plus physics--all diverging from the primary aim of the NEURON Forum, which is to address questions about NEURON. Anyone else who wants to, ...
by ted
Tue Oct 29, 2019 9:30 pm
Forum: Getting started
Topic: Spike configuration at internode sections of myelinated axon
Replies: 5
Views: 299

Re: Spike configuration at internode sections of myelinated axon

The term "spike configuration" will not be understood by neuroscientists. Perhaps you mean "spike waveform"?
by ted
Mon Oct 28, 2019 2:29 pm
Forum: Getting started
Topic: construct a single myelinated axon
Replies: 10
Views: 548

Re: construct a single myelinated axon

if I want to see the spike propagation along a myelinated axon, can I refer to the work done(the effect of changing the diameter of the axon on the capacitance) by Moore using pas instead of extracellular Yes, if your intent is to see intracellular potential relative to ground. If the model uses ex...
by ted
Mon Oct 28, 2019 1:09 pm
Forum: The GUI
Topic: saving recordings automatically
Replies: 1
Views: 346

Re: saving recordings automatically

It's called programming. If you've never done it before, it's time to start learning, hire somebody to do it for you, or develop a collaboration with somebody who knows how. We strongly suggest Python for all new programming projects. Fortunately, it's easy to use GUI-built models with Python. Here'...
by ted
Mon Oct 28, 2019 12:37 pm
Forum: NEURON + Python
Topic: Parallel NMODL array assignment
Replies: 8
Views: 488

Re: Parallel NMODL array assignment

One question that may affect the answer: do the values in the array represent breakpoints in a piecewise linear approximation to a function, or are they merely a set of indexed values?
by ted
Mon Oct 28, 2019 12:20 pm
Forum: NEURON + Python
Topic: Parallel NMODL array assignment
Replies: 8
Views: 488

Re: Parallel NMODL array assignment

Thank you for clarifying your question. To me, the most direct approach would involve a POINTER and a VERBATIM block with a bit of C code that dereferences the proper value in the array. That said, I'll have to pass this on to someone else for an example implementation.
by ted
Mon Oct 28, 2019 12:10 pm
Forum: NEURON + Python
Topic: How to add synapses to an Adex model
Replies: 4
Views: 283

Re: How to add synapses to an Adex model

You want help implementing synaptic inputs to a model cell but say nothing about how you implemented the model cell--yet that is the very information required to give you a useful answer. Did you implement the model cell as an ARTIFICIAL_CELL, a POINT_PROCESS, or as a section to which NMODL-implemen...
by ted
Tue Oct 22, 2019 6:46 pm
Forum: NEURON + Python
Topic: accessing the same instantiation of a cell template from another python script
Replies: 4
Views: 411

Re: accessing the same instantiation of a cell template from another python script

Download https://www.neuron.yale.edu/ftp/ted/ineuron/extracellular_stim_and_rec.zip and examine xtra.mod. See how the GLOBAL variable called "is" is used to tell every instance of xtra the value of the current applied by the stimulating electrode. Note the use of BEFORE BREAKPOINT to ensure that all...
by ted
Tue Oct 22, 2019 9:43 am
Forum: Getting started
Topic: construct a single myelinated axon
Replies: 10
Views: 548

Re: construct a single myelinated axon

You need a good course in cellular neurophysiology. That would answer many of your questions. So if I use extracellular to construct myelinated axon(even with nodes of Ranvier), then I won't be able to see the spike along the myelinated axon at the internode sections(which I tried and the voltage re...
by ted
Mon Oct 21, 2019 11:49 pm
Forum: Reaction-diffusion in NEURON
Topic: The equilibrium between the FS and external
Replies: 20
Views: 723

Re: The equilibrium between the FS and external

Articles generally include the authors' contact information, which is typically provided near the abstract. Check the publisher's web site. If that doesn't work, do an internet search on their names or check the Society for Neuroscience member list. AFAIK, many if not most of the authors are still a...
by ted
Mon Oct 21, 2019 10:01 am
Forum: NEURON + Python
Topic: Parallel NMODL array assignment
Replies: 8
Views: 488

Re: Parallel NMODL array assignment

Use a density mechanism that has a GLOBAL variable. Insert that mechanism into all sections that you want to affect. Use the Vector class's play() method to drive that variable in a single section with the values stored in a single array. Since the variable is GLOBAL, all instances of the density me...
by ted
Mon Oct 21, 2019 9:58 am
Forum: NEURON hacks
Topic: Convert Neuron models to C
Replies: 1
Views: 705

Re: Convert Neuron models to C

Yes. It's called rewriting the model implementation from scratch. It is done by a programmer.
by ted
Mon Oct 21, 2019 9:49 am
Forum: Getting started
Topic: construct a single myelinated axon
Replies: 10
Views: 548

Re: construct a single myelinated axon

I'm constructing a single myelinated axon without any nodes, just a soma connected to myelinated axon to see how the AP propagates with the change of the diameter. Then there won't be any actual "spike propagation" along your axon, even if the axolemma is full of voltage-gated channels. Why? Becaus...
by ted
Mon Oct 21, 2019 9:43 am
Forum: NEURON + Python
Topic: Problems using VClamp
Replies: 1
Views: 203

Re: Problems using VClamp

I have a cell with multiple sections where I want to inject a specific voltage in mV, coming from a cell in NEST. Since I cannot form any synapses between them, I thought about artificially stimulating the NEURON cells with the exact value that should be sent by the NEST cells. For this matter, I c...
by ted
Sun Oct 20, 2019 11:20 pm
Forum: Getting started
Topic: construct a single myelinated axon
Replies: 10
Views: 548

Re: construct a single myelinated axon

1. If I use the pas mechanism for the biophysical part of the axon, then I'm constructing a myelinated axon? No. To build a model of myelinated axon, you have to represent the electrical effects of the myelin sheath. pas is used to represent a voltage-independent membrane conductance. 2. NEURON con...