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:

• HillTononi_model

For examples, see:

• Intrinsic currents spiking

• Intrinsic currents subthreshold

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

• Multiarea Hill-Tononi thalamocortical network model

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

See also

Neuron, Hill-Tononi Plasticity