Extracelluar stimulation with prepulse waveforms

[bchenley]

I am new to NEURON. I would like input on how to simulate: (1) extracellular stimulation (2) current prepulse waveforms

[ted]

Extracellular stimulation is discussed in the Hot tips area of the Forum http://www.neuron.yale.edu/phpBB/viewforum.php?f=28

Not sure what you mean by prepulse--unless it's just that the time course of extracellular stimulation has an extra wiggle of some sort at the beginning. If that's the case, the answer is: once you get extracellular stimulation going, you can assert any time course you like.

[bchenley]

Oh, what I meant by prepulse is that, for a given desired stimulus, there is an initial stimulus (usually of different amplitude and/or sign) right before it. Basically, I am trying to demonstrate prepulse inhibition (http://en.wikipedia.org/wiki/Prepulse_inhibition).

[ted]

Then the answer is still "yes."

[bchenley]

I have the extracellular stimulation working, but I am having trouble implementing the prepulses. I am trying to work with stim.hoc; it only gives you the option of changing the delay, duration, and amplitude for a single pulse. Is there a way in to incorporate more than one?

[ted]

I assume you're referring to the stim.hoc that is one of the files included in extracellular_stim_and_rec.zip. All the source code is there; feel free to revise it in any way you like. The original implementation is rather simple-minded--sets up a single pulse with amplitude 1, then multiplies by a scale factor. At the very least you'll want two pulses with independently adjustable durations and amplitudes, separated by an adjustable interpulse delay. This can be done with the Vector class and its methods, which are documented at http://www.neuron.yale.edu/neuron/stati ... tml#Vector. The graphical user interface to specify these parameters will have to be revised accordingly--see documentation of the "button-menu-panel" items in the Programmer's Reference http://www.neuron.yale.edu/neuron/stati ... menu-panel