NetStim

Moderator: wwlytton

Post Reply
maria.kesa
Posts: 36
Joined: Thu Nov 12, 2015 10:45 am

NetStim

Post by maria.kesa » Sat Feb 13, 2016 1:18 pm

Hello,

I need to stimulate a population of cells with a spike train for a certain time period. Would NetStim be the right solution? However, I can't find how to specify the time period for which to emit the spikes to the target cell. Do I have to instead specify the number of spikes as s.number?

Thank you,
Maria

ted
Site Admin
Posts: 5057
Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
Contact:

Re: NetStim

Post by ted » Mon Feb 15, 2016 12:35 am

maria.kesa wrote:Would NetStim be the right solution?
Yes.
I can't find how to specify the time period for which to emit the spikes to the target cell.
The Programmer's Reference documentation of the NetStim class states which parameters are available.
https://www.neuron.yale.edu/neuron/stat ... ml#NetStim
Was it difficult to find that in the index of the Programmer's Reference, or are the descriptions of the parameters unclear?

maria.kesa
Posts: 36
Joined: Thu Nov 12, 2015 10:45 am

Re: NetStim

Post by maria.kesa » Fri Feb 19, 2016 2:10 pm

Thank you, Ted!
I initially found this document on a google search http://www.neuron.yale.edu/neuron/stati ... ml#NetStim I guess the content is the same as in what you referenced.

I just couldn't understand how you set it so that the spike trains terminate at a predefined time. Because you have s.start and s.number and s.interval, but no s.stop. I guess that you coud mutliply s.number with s.interval and that would be an estimate of when the process terminates, but is there a more direct way to do that (since there's also some randomness involved)? Any help would be appreciated.

Maria

ted
Site Admin
Posts: 5057
Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
Contact:

Re: NetStim

Post by ted » Fri Feb 19, 2016 3:00 pm

maria.kesa wrote:I initially found this document on a google search http://www.neuron.yale.edu/neuron/stati ... ml#NetStim I guess the content is the same as in what you referenced.
Looks like the Google search picked up the old documentation. Most of the new documentation is the same as the old documentation, but changes or additions made since a couple of years ago will only appear in the new Programmer's Reference.
I just couldn't understand how you set it so that the spike trains terminate at a predefined time. . . . is there a more direct way to do that (since there's also some randomness involved)?
I assume you're using a NetStim and you have made its "noise" parameter be > 0. In that case, the easiest way to force the NetStim to stop generating events is to deliver an event to it that has negative weight. Using events to control a NetStim is discussed in the Programmer's Reference documentation of the NetStim class, which I quote here:
NetStim can also be be triggered by an input event. i.e serve as the target of a NetCon. If the stimulator is in the on=0 state and receives a positive weight event, then the stimulator changes to the on=1 state and goes through its burst sequence before changing to the on=0 state. During that time it ignores any positive weight events. If, in the on=1 state, the stimulator receives a negative weight event, the stimulator will change to the off state. In the off state, it will ignore negative weight events. A change to the on state immediately causes the first spike.

maria.kesa
Posts: 36
Joined: Thu Nov 12, 2015 10:45 am

Re: NetStim

Post by maria.kesa » Sat Feb 20, 2016 2:09 pm

Thanks, Ted, but what does it mean to receive a positive or negative weight event?

Maria

ted
Site Admin
Posts: 5057
Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
Contact:

Re: NetStim

Post by ted » Sun Feb 21, 2016 2:17 pm

maria.kesa wrote:what does it mean to receive a positive or negative weight event?
Refers to the sign of the weight of the NetCon that delivers the event.

Post Reply