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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 adaptive threshold.

  • Repolarizing potassium current instead of hard reset.

  • AMPA, NMDA, GABA_A, and GABA_B conductance-based synapses with beta-function (difference of exponentials) time course.

  • Voltage-dependent NMDA with instantaneous or two-stage unblocking 1, 2.

  • Intrinsic currents I_h, I_T, I_Na(p), and I_KNa.

  • Synaptic “minis” are not implemented.

For implementation details see:

For examples, see:

For an example network model using ht_neuron (based on 1), see:

Parameters

V_m

mV

Membrane potential

tau_m

ms

Membrane time constant applying to all currents except repolarizing K-current (see 1, p 1677)

t_ref

ms

Refractory time and duration of post-spike repolarizing potassium current (t_spike in 1)

tau_spike

ms

Membrane time constant for post-spike repolarizing potassium current

voltage_clamp

boolean

If true, clamp voltage to value at beginning of

simulation

(default: false, mainly for testing)

theta

mV

Threshold

theta_eq

mV

Equilibrium value

tau_theta

ms

Time constant

g_KL

nS

Conductance for potassium leak current

E_K

mV

Reversal potential for potassium leak currents

g_NaL

nS

Conductance for sodium leak currents

E_Na

mV

Reversal potential for Na leak currents

tau_D_KNa

ms

Relaxation time constant for I_KNa

receptor_types

Dictionary mapping synapse names to ports on neuron model

recordables

List of recordable quantities

{E_rev,g_peak,tau_rise,tau_decay}_{AMPA,NMDA,GABA_A,GABA_B}

Reversal potentials, peak conductances and time constants for synapses (tau_rise/tau_decay correspond to tau_1/tau_2 in the paper)

V_act_NMDA, S_act_NMDA, tau_Mg_{fast, slow}_NMDA

Parameters for voltage dependence of NMDA- conductance, see above

instant_unblock_NMDA

Instantaneous NMDA unblocking (default: false)

{E_rev,g_peak}_{h,T,NaP,KNa}

Reversal potential and peak conductance for intrinsic currents

{N}_{T,NaP}

Exponent activation term m_inf, corresponding to number of activation particles

equilibrate

If given and true, time-dependent activation and inactivation state variables (h, m) of intrinsic currents and NMDA channels are set to their equilibrium values during this SetStatus call; otherwise they retain their present values.

Note

Conductances are unitless in this model and currents are in mV.

Sends

SpikeEvent

Receives

SpikeEvent, CurrentEvent, DataLoggingRequest

References

1(1,2,3,4,5)

Hill S, Tononi G (2005). Modeling sleep and wakefulness in the thalamocortical system. Journal of Neurophysiology. 93:1671-1698. DOI: https://doi.org/10.1152/jn.00915.2004

2

Vargas-Caballero M, Robinson HPC (2003). A slow fraction of Mg2+ unblock of NMDA receptors limits their contribution to spike generation in cortical pyramidal neurons. Journal of Neurophysiology 89:2778-2783. DOI: https://doi.org/10.1152/jn.01038.2002