* simulation from: Lytton WW; Contreras D; Destexhe A; Steriade M. Dynamic interactions determine partial thalamic quiescence in a computer network model of spike-and-wave seizures. J Neurophysiol, 77:1679-1696, 1997. Fig 7 on p 1688 (jnphys77:1679.pdf) Simulation of figure 7 may take several minutes. fig7.gif shows the output of the simulation. A phase plane analysis of a two cell interaction between a thalamocortical neuron (TC) and a thalamic reticularis neuron (RE). Figure legend : Analysis of spontaneous transition from mutual to quiescent mode with bursting viewed in the RE T-channel m/h plane. A. RE neuron voltage trace (A1) and TC voltage trace (A2) shows 8 bursts of mutual activity followed by switch into the quiescent state. Color for each cycle give the key for the phase planes below. Interburst intervals are depicted in panel Ba. Alternating bursts are shown in panels Bb and Bc. Initial oscillation appears to be approximately period-2 with burst alternating with an interburst depolarization. B. Apparent approximate period-2 oscillation illustrated to be period-4: four cycles occur before the cycle repeats. In each phase plane, abscissa gives the value of mT (T channel activation), ordinate the value of hT (T channel inactivation). Trajectories run counterclockwise. Interbursts alternated between large cycles (solid line type) and small cycles (dashed line type) Burst Bb showed a progression of gradually increasing hT, while burst Bc was more coherent and showed no regular shift. The inner loop in Ba gradually collapsed to terminate the oscillation. The subsequent interburst (grey dashed) was similar in extent to large cycle. C. Inner and outer interburst cycles seen in the voltage-calcium plane corresponded to Ba-inner and Ba-outer respectively. The collapse of the inner cycle is not as clear as in Ba, however. Trajectories run clockwise. * COMPILE and RUN: nrnivmodl RUN: $CPU/special init.hoc - RE-RUN: simsim() allows you to simulate a simulation by graphing out the saved data slowly so that you can see the phase planes unfold in time (can be slowed down by setting disp_delay to a large number) * notes 1) graphics box comes up with graphs set to "New View" to allow closer inspection of phase planes 2) use 'vecpanel()' call to bring up interactive tool for generating other graphics 3) original figure only showed data from about t=600 rather than from beginning * hoc list: from ~/nrniv/tcre2 geom.hoc v5, network.hoc v39, params.hoc v108 run.hoc v105 init.hoc master hoc file geom.hoc defines single compartment cells and column network.hoc creates cells, connectivity and stimulation params.hoc sets parameters run.hoc additional initialization routines, graphing boxes.hoc make large arrays of graphs. not used here due to specialized layout declist.hoc list handling routines decvec.hoc vector handling routines default.hoc flags and values grvec.hoc main vector graphic routines local.hoc additional initialization routines nrnoc.hoc main initialization routines simctrl.hoc simulation control package using RCS * mod list HH_traub.mod SUFFIX hh2 IAHP_destexhe.mod: SUFFIX iahp ICAN_destexhe.mod: SUFFIX ican IT2_huguenard.mod: SUFFIX it2 IT_wang.mod SUFFIX it Ih_old.mod: SUFFIX iar calciumpump_destexhe.mod SUFFIX cad gen.mod: POINT_PROCESS gen nmda.mod: POINT_PROCESS NMDA passiv.mod: SUFFIX Pass presyn.mod: POINT_PROCESS PRESYN pulse.mod: POINT_PROCESS PULSE AMPA.mod POINT_PROCESS AMPA NMDA.mod POINT_PROCESS NMDA GABAB1.mod POINT_PROCESS GABAB1 GABALOW.mo POINT_PROCESS GABALOW rand.mod: SUFFIX nothing * mechanisms and processes used Pass leak current hh2 Hodgin-Huxley INa and IK it TC IT current iar Ih current it2 reticular IT current iahp slow IAHP ican slow ICAN cad calcium pump gen random spike generator AMPA NMDA IClamp Changelog --------- 2022-05: Updated MOD files to contain valid C++ and be compatible with the upcoming versions 8.2 and 9.0 of NEURON.