Command: tsodyks2_synapse

NEST HelpDesk Command Index NEST Quick Reference

Name:
 tsodyks2_synapse - Synapse type with short term plasticity.

Description:
   This synapse model implements synaptic short-term depression and short-term facilitation
   according to [1] and [2]. It solves Eq (2) from [1] and modulates U according to eq. (2) of [2].

   This connection merely scales the synaptic weight, based on the spike history and the 
   parameters of the kinetic model. Thus, it is suitable for all types of synaptic dynamics,
   that is current or conductance based.

   The parameter A_se from the publications is represented by the
   synaptic weight. The variable x in the synapse properties is the
   factor that scales the synaptic weight.

Parameters:
 
     The following parameters can be set in the status dictionary:
     U          double - probability of release increment (U1) [0,1], default=0.5
     u          double - Maximum probability of release (U_se) [0,1], default=0.5
     x          double - current scaling factor of the weight, default=U 
     tau_rec    double - time constant for depression in ms, default=800 ms
     tau_rec    double - time constant for facilitation in ms, default=0 (off)

  Notes:

     Under identical conditions, the tsodyks2_synapse produces
     slightly lower peak amplitudes than the tsodyks_synapse. However,
     the qualitative behavior is identical. The script
     test_tsodyks2_synapse.py in the examples compares the two synapse
     models.


References:
   [1] Tsodyks, M. V., & Markram, H. (1997). The neural code between neocortical pyramidal neurons 
       depends on neurotransmitter release probability. PNAS, 94(2), 719-23.
   [2] Fuhrmann, G., Segev, I., Markram, H., & Tsodyks, M. V. (2002). Coding of temporal 
       information by activity-dependent synapses. Journal of neurophysiology, 87(1), 140-8.
   [3] Maass, W., & Markram, H. (2002). Synapses as dynamic memory buffers. Neural networks, 15(2), 155–61.

Transmits:
 SpikeEvent
       
FirstVersion:
 October 2011
Author:
 Marc-Oliver Gewaltig, based on tsodyks_synapse by Moritz Helias
SeeAlso:tsodyks_synapse synapsedict stdp_synapse static_synapse
Source:
 /home/abuild/rpmbuild/BUILD/nest-2.4.1/models/tsodyks2_connection.h

NEST HelpDesk Command Index NEST Quick Reference

© 2000-2010 The NEST Initiative