Command: ht_neuron

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Name:
 ht_neuron - Neuron model after Hill & Tononi (2005).

Description:
 
   This model neuron implements a slightly modified version of the
   neuron model described in [1]. The most important properties are:

   - Integrate-and-fire with threshold that is increased on spiking
     and decays back to an equilibrium value.
   - No hard reset, but repolarizing potassium current.
   - AMPA, NMDA, GABA_A, and GABA_B conductance-based synapses with
     beta-function (difference of two exponentials) time course.
   - Intrinsic currents I_h (pacemaker), I_T (low-threshold calcium),
     I_Na(p) (persistent sodium), and I_KNa (depolarization-activated
     potassium).

   In comparison to the model described in the paper, the following
   modifications were mare:

   - NMDA conductance is given by g(t) = g_peak * m(V), where

       m(V) = 1 / ( 1 + exp( - ( V - NMDA_Vact ) / NMDA_Sact ) ) 

     This is an approximation to the NMDA model used in [2].

   - Several apparent typographical errors in the descriptions of 
     the intrinsic currents were fixed, hopefully in a meaningful
     way.

   I'd like to thank Sean Hill for giving me access to his 
   simulator source code.
   
   See examples/hilltononi for usage examples.

   Warning:
   THIS MODEL NEURON HAS NOT BEEN TESTED EXTENSIVELY!

Parameters:
 
   V_m  -  membrane potential
   spike_duration - duration of re-polarizing potassium current
   Tau_m - membrane time constant applying to all currents but repolarizing K-current
           (see [1, p 1677])
   Tau_spike - membrane time constant applying to repolarizing K-current
   Theta, Theta_eq, Tau_theta - Threshold, equilibrium value, time constant
   g_KL, E_K, g_NaL, E_Na - conductances and reversal potentials for K and Na leak currents

   {AMPA,NMDA,GABA_A,GABA_B}_{E_rev,g_peak,Tau_1,Tau_2} 
   - reversal potentials, peak conductances and time constants for synapses
     (Tau_1: rise time, Tau_2: decay time, Tau_1 < Tau_2)

   NMDA_Sact, NMDA_Vact - Parameters for voltage dependence of NMDA-synapse, see eq. above

   {h,T,NaP,KNa}_{E_rev,g_peak} - reversal potential and peak conductance for intrinsic currents

   receptor_types - dictionary mapping synapse names to ports on neuron model
   recordables - list of recordable quantities.

Author:
 Hans Ekkehard Plesser

Sends:
 SpikeEvent
   
Receives:
 SpikeEvent, CurrentEvent, DataLoggingRequest
   
FirstVersion:
 October 2009

References:
   [1] S Hill and G Tononi (2005). J Neurophysiol 93:1671-1698.
   [2] ED Lumer, GM Edelman, and G Tononi (1997). Cereb Cortex 7:207-227.

SeeAlso:ht_synapse
Source:
 /home/abuild/rpmbuild/BUILD/nest-2.4.1/models/ht_neuron.h

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