Modify existing cell type

This function modifies parameters of an existing cell type in the current session. Parameters can be updated selectively. If a parameter is not specified (or is specified as NULL), the existing value will be kept.

Usage

modify.cell.type(
  type_name,
  valence = NULL,
  tau_fast = NULL,
  tau_slow = NULL,
  tau_Vs = NULL,
  I_slow = NULL,
  U_Vs = NULL,
  max_spike_rate = NULL,
  transmission_velocity = NULL,
  spine_density = NULL,
  axon_target = NULL,
  I_spike = NULL,
  spike_potential = NULL,
  resting_potential = NULL,
  threshold = NULL,
  leak_conductance = NULL,
  axon_branch_count = NULL,
  dendrite_branch_count = NULL,
  branch_independence = NULL,
  branch_spread = NULL,
  apical_target_layer = NULL
)

Arguments

type_name

Character string giving name of the cell type, e.g. "pyramidal", "PV", "SST", etc.

valence

Valence of each neuron type, +1 for excitatory, -1 for inhibitory.

tau_fast

Time constant (ms) of the fast sodium (Na+) current (positive current, time to flow in).

tau_slow

Time constant (ms) of the slow calcium (Ca2+) current (negative current, time to pump out).

tau_Vs

Time constant (ms) for restoring presynaptic vesicles, i.e., recovery from short-term depression (STD).

I_slow

Slow-current molecule (e.g., Ca2+) influx as concentration per spike (concentration/spike).

U_Vs

Utilization ratio (concentration/spike) of vesicles per spike.

max_spike_rate

Constant (spikes/ms) controlling estimation of spike rate and its maximum value.

transmission_velocity

Transmission velocity (in microns/ms) along axon, for each neuron type.

spine_density

Scale controlling percentage of dendrite nodes with spines: zero means none, one means all.

axon_target

Character string giving target of axon projections, one of: "spine", "dendrite_shaft", "soma", or "axon_shaft".

I_spike

Spike current, in pA; absolute value plus a little bit used as dHdv_bound.

spike_potential

Peak potential during a spike, in mV.

resting_potential

Resting potential, in mV; absolute value plus a little bit used as v_bound.

threshold

Spike threshold, in mV.

leak_conductance

Conductance controlling the leak current, I_leak = leak_conductance * (resting_potential - v), in nS.

axon_branch_count

Expected number of axon branches.

dendrite_branch_count

Expected number of dendrite branches.

branch_independence

Scale between 0 and 1; 0 = all branches connect to soma from single segment, 1 = all branches connect directly to soma.

branch_spread

Scale between 0 and 1; 0 = no tendency to extend away from soma, 1 = straight line away from soma.

apical_target_layer

Character string giving target layer for apical dendrites.

Value

Nothing.