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 <../model_details/HillTononiModels.ipynb>`_

For examples, see:

- :doc:`../auto_examples/intrinsic_currents_spiking`
- :doc:`../auto_examples/intrinsic_currents_subthreshold`

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

- `Multiarea Hill-Tononi thalamocortical network model
  <https://github.com/ricardomurphy/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, |  Parameters for voltage dependence of NMDA-    |
|tau_Mg_{fast, slow}_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] 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
++++++++
:doc:`Neuron <index_neuron>`, :doc:`Hill-Tononi Plasticity <index_Hill-Tononi plasticity>`