Thalamic interneuron multicompartment model (Zhu et al. 1999)

 Download zip file   Auto-launch 
Help downloading and running models
Accession:116862
This is an attempt to recreate a set of simulations originally performed in 1994 under NEURON version 3 and last tested in 1999. When I ran it now it did not behave exactly the same as previously which I suspect is due to some minor mod file changes on my side rather than due to any differences among versions. After playing around with the parameters a little bit I was able to get something that looks generally like a physiological trace in J Neurophysiol, 81:702--711, 1999, fig. 8b top trace. This sad preface is simply offered in order to encourage anyone who is interested in this model to make and post fixes. I'm happy to help out. Simulation by JJ Zhu To run nrnivmodl nrngui.hoc
References:
1 . Zhu JJ, Uhlrich DJ, Lytton WW (1999) Burst firing in identified rat geniculate interneurons. Neuroscience 91:1445-60 [PubMed]
2 . Zhu JJ, Lytton WW, Xue JT, Uhlrich DJ (1999) An intrinsic oscillation in interneurons of the rat lateral geniculate nucleus. J Neurophysiol 81:702-11 [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Neuron or other electrically excitable cell;
Brain Region(s)/Organism: Thalamus;
Cell Type(s):
Channel(s): I Na,t; I L high threshold; I T low threshold; I K,leak; I h; I K,Ca; I CAN;
Gap Junctions:
Receptor(s):
Gene(s):
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Bursting; Oscillations;
Implementer(s): Zhu, J. Julius [jjzhu at virginia.edu];
Search NeuronDB for information about:  I Na,t; I L high threshold; I T low threshold; I K,leak; I h; I K,Ca; I CAN;
/
b09jan13
readme.html
AMPA.mod
cadecay.mod
clampex.mod *
cp.mod *
cp2.mod *
GABAA.mod
GABAB.mod
HH2.mod *
Iahp.mod *
Ican.mod *
Ih.mod *
IL.mod
IL3.mod *
IT.mod *
IT2.mod *
kdr2.mod *
kleak.mod *
kmbg.mod
naf2.mod *
nap.mod *
NMDA.mod
nthh.mod *
ntIh.mod *
ntleak.mod
ntt.mod *
pregencv.mod
vecst.mod
batch_.hoc
bg_cvode.inc
misc.h
mosinit.hoc *
netcon.inc
screenshot.jpg
                            
: $Id: pregencv.mod,v 1.1 1998/08/13 16:44:00 billl Exp $
: Id: pregen.mod,v 1.1 1998/07/01 21:11:23 hines Exp 
: comments at end

INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)}

NEURON	{ 
  POINT_PROCESS SpikeGenerator
  RANGE x, spk, lastspk
  RANGE fast_invl, slow_invl, burst_len, start, end
  RANGE noise
  GLOBAL dummy : prevent vectorization for use with CVODE
}

PARAMETER {
	fast_invl	= 1		: time between spikes in a burst (msec)
	slow_invl	= 50		: burst period (msec)
: actually, above is interburst period in conformity with original version
: see
	burst_len	= 10		: burst length (# spikes)
	start		= 50		: start of first interburst interval
	end		= 1e10		: time to stop bursting
	noise		= 0		: amount of randomness (0.0 - 1.0)
}

ASSIGNED {
	x
	burst
	event
	burst_off
	burst_on
	toff
	dummy
}

PROCEDURE seed(x) {
	set_seed(x)
}

INITIAL {
	toff = 1e9
	x = -90
	burst = 0
	event = start
	event_time()
	generate()
}	

BREAKPOINT {
	SOLVE generate METHOD cvode_t
}

FUNCTION interval(mean (ms)) (ms) {
	if (mean <= 0.) {
		mean = .01 : I would worry if it were 0.
	}
	if (noise == 0) {
		interval = mean
	}else{
		interval = (1. - noise)*mean + noise*exprand(mean)
	}
}

PROCEDURE event_time() {
	if (burst != 0.) {
		event = event + interval(fast_invl)
		if (event > burst_on + burst_off) {
			burst = 0.
		}
	}else{
		burst = 1.
: if slow_invl from beginning of burst to beginning of burst
:		event = event + interval(slow_invl - (burst_len-1)*fast_invl)
: use following if slow_invl is interburst interval
		event = event + interval(slow_invl)
		burst_on = event
		burst_off = interval((burst_len - 1)*fast_invl)-1e-6
	}
	if (event > end) {
		event = -1e5
	}
}

PROCEDURE generate() {
	if (at_time(event)) {
		x = 20
		toff = event + .1
		event_time()
	}
	if (at_time(toff)) {
		x = -90
	}
}

COMMENT
Presynaptic spike generator
---------------------------

This mechanism has been written to be able to use synapses in a single
neuron receiving various types of presynaptic trains.  This is a "fake"
presynaptic compartment containing a fast spike generator.  The trains
of spikes can be either periodic or noisy (Poisson-distributed), and 
either tonic or bursting.

Parameters;
   noise: 	between 0 (no noise-periodic) and 1 (fully noisy)
   fast_invl: 	fast interval, mean time between spikes (ms)
   slow_invl:	slow interval, mean burst silent period (ms), 0=tonic train
   burst_len: 	mean burst length (nb. spikes)

Written by Z. Mainen, modified by A. Destexhe, The Salk Institute

Modified by Michael Hines for use with CVode

ENDCOMMENT


Loading data, please wait...