TABLE A4.
Connectivity for the initial model represented in Fig. 1
| Source Population | Target Population | Synaptic Type | Minimum Conduction Time | Maximum Conduction Time | No. of Terminals | Synaptic Strength | Source Population N | Target Population N | Divergence | Mean No. of Terminals | Convergence |
|---|---|---|---|---|---|---|---|---|---|---|---|
| I-Driver | I-Dec | Ex | 0 | 4 | 100 | 0.006 | 300 | 300 | 84.99 ± 3.14 | 1.18 | 84.99 ± 7.54 |
| I-Driver | I-Aug-BS | Ex | 0 | 5 | 100 | 0.005 | 300 | 300 | 84.98 ± 3.14 | 1.18 | 84.98 ± 7.44 |
| I-Driver | I-Driver | Ex | 0 | 4 | 50 | 0.003 | 300 | 300 | 46.34 ± 1.76 | 1.08 | 46.34 ± 5.84 |
| E-Dec-P | I-Driver | Inh_2 | 0 | 5 | 100 | 0.012 | 300 | 300 | 85.20 ± 3.05 | 1.17 | 85.20 ± 9.59 |
| E-Dec-P | E-Aug-early | Inh_1 | 0 | 2 | 150 | 0.006 | 300 | 300 | 118.24 ± 4.01 | 1.27 | 118.24 ± 8.86 |
| E-Dec-P | E-Aug-late | Inh_1 | 2 | 4 | 150 | 0.02 | 300 | 300 | 118.10 ± 3.94 | 1.27 | 118.10 ± 9.61 |
| E-Dec-P | VRC IE | Inh_1 | 0 | 2 | 24 | 0.2 | 300 | 99 | 21.36 ± 1.41 | 1.12 | 64.74 ± 5.23 |
| E-Dec-P | I-Dec | Inh_1 | 0 | 0 | 100 | 0.2 | 300 | 300 | 85.07 ± 3.10 | 1.18 | 85.07 ± 7.21 |
| E-Dec-P | PRG I | Inh_2 | 0 | 1 | 100 | 0.001 | 300 | 100 | 63.24 ± 3.09 | 1.58 | 189.71 ± 8.08 |
| E-Dec-P | I-Aug-BS | Inh_1 | 0 | 2 | 50 | 0.1 | 300 | 300 | 46.19 ± 1.72 | 1.08 | 46.19 ± 5.43 |
| E-Dec-P | E-Aug-BS | Inh_1 | 0 | 5 | 125 | 0.015 | 300 | 300 | 102.22 ± 3.56 | 1.22 | 102.22 ± 9.65 |
| I-Dec | E-Aug-early | Inh_1 | 0 | 2 | 115 | 1.25 | 300 | 300 | 95.67 ± 3.39 | 1.20 | 95.67 ± 7.14 |
| I-Dec | E-Dec-P | Inh_1 | 0 | 5 | 115 | 0.3 | 300 | 300 | 95.60 ± 3.52 | 1.20 | 95.60 ± 7.69 |
| I-Dec | I-Aug-BS | Inh_2 | 0 | 1 | 210 | 0.006 | 300 | 300 | 151.59 ± 5.04 | 1.39 | 151.59 ± 8.80 |
| I-Dec | E-Aug-late | Inh_2 | 0 | 5 | 115 | 1.0 | 300 | 300 | 95.71 ± 3.51 | 1.20 | 95.71 ± 7.84 |
| I-Dec | VRC IE | Inh_1 | 0 | 4 | 100 | 0.029 | 300 | 99 | 63.21 ± 3.10 | 1.58 | 191.54 ± 7.38 |
| I-Dec | E-Dec-T | Inh_1 | 0 | 5 | 100 | 0.015 | 300 | 300 | 84.90 ± 2.96 | 1.18 | 84.90 ± 9.43 |
| I-Dec | E-Aug-BS | Inh_1 | 0 | 5 | 125 | 0.045 | 300 | 300 | 102.22 ± 3.56 | 1.22 | 102.22 ± 9.65 |
| I-Dec | PRG EI | Ex | 0 | 1 | 100 | 0.0005 | 300 | 100 | 63.47 ± 3.07 | 1.58 | 190.42 ± 9.05 |
| I-Aug-BS | I-Aug-BS | Ex | 0 | 5 | 50 | 0.02 | 300 | 300 | 45.99 ± 1.77 | 1.09 | 45.99 ± 5.31 |
| I-Aug-BS | PRG I | Ex | 0 | 1 | 100 | 0.002 | 300 | 100 | 63.43 ± 3.01 | 1.58 | 190.28 ± 11.40 |
| I-Aug-BS | Phrenic | Ex | 0 | 3 | 50 | 0.02 | 300 | 300 | 46.35 ± 1.71 | 1.08 | 46.35 ± 6.00 |
| I-Aug-BS | VRC IE | Ex | 0 | 5 | 50 | 0.004 | 300 | 99 | 39.38 ± 2.42 | 1.27 | 119.34 ± 6.86 |
| E-Aug-early | E-Dec-P | Inh_1 | 0 | 2 | 110 | 0.014 | 300 | 300 | 91.85 ± 3.43 | 1.20 | 91.85 ± 8.07 |
| E-Aug-early | I-Dec | Inh_1 | 0 | 5 | 100 | 0.05 | 300 | 300 | 85.13 ± 2.98 | 1.17 | 85.13 ± 7.70 |
| E-Aug-early | I-Aug-BS | Inh_1 | 0 | 2 | 150 | 0.06 | 300 | 300 | 118.48 ± 4.08 | 1.27 | 118.48 ± 8.37 |
| E-Aug-early | VRC IE | Inh_1 | 0 | 2 | 24 | 0.02 | 300 | 99 | 21.46 ± 1.29 | 1.12 | 65.02 ± 6.96 |
| E-Aug-early | Phrenic | Inh_1 | 0 | 2 | 150 | 0.1 | 300 | 300 | 118.31 ± 4.21 | 1.27 | 118.31 ± 7.57 |
| E-Aug-early | E-Dec-T | Inh_1 | 0 | 2 | 100 | 0.006 | 300 | 300 | 85.13 ± 2.94 | 1.17 | 85.13 ± 9.11 |
| E-Aug-early | E-Aug-late | Inh_1 | 0 | 2 | 50 | 0.001 | 300 | 300 | 46.01 ± 1.81 | 1.09 | 46.01 ± 6.57 |
| E-Aug-late | E-Aug-early | Inh_1 | 0 | 2 | 50 | 0.004 | 300 | 300 | 46.23 ± 1.78 | 1.08 | 46.23 ± 9.43 |
| E-Aug-late | I-Dec | Inh_1 | 0 | 4 | 55 | 0.01 | 300 | 300 | 50.33 ± 1.87 | 1.09 | 50.33 ± 6.68 |
| E-Aug-late | I-Aug-BS | Inh_1 | 0 | 2 | 150 | 0.06 | 300 | 300 | 118.09 ± 3.79 | 1.27 | 118.09 ± 7.65 |
| E-Aug-late | E-Dec-P | Inh_1 | 0 | 2 | 115 | 0.014 | 300 | 300 | 95.57 ± 3.26 | 1.20 | 95.57 ± 9.85 |
| E-Aug-late | Phrenic | Inh_1 | 0 | 2 | 150 | 0.12 | 300 | 300 | 118.14 ± 4.18 | 1.27 | 118.14 ± 8.44 |
| E-Aug-late | VRC IE | Inh_1 | 0 | 2 | 24 | 0.02 | 300 | 99 | 21.32 ± 1.39 | 1.13 | 64.62 ± 7.03 |
| E-Aug-late | E-Dec-T | Inh_1 | 0 | 2 | 100 | 0.015 | 300 | 300 | 85.18 ± 3.01 | 1.17 | 85.18 ± 6.53 |
| E-Aug-late | E-Aug-BS | Inh_1 | 0 | 5 | 100 | 0.01 | 300 | 300 | 85.20 ± 3.05 | 1.17 | 85.20 ± 9.59 |
| E-Aug-late | PRG E | Ex | 0 | 1 | 100 | 0.005 | 300 | 100 | 63.34 ± 3.11 | 1.58 | 190.03 ± 8.09 |
| VRC IE | I-Dec | Inh_2 | 0 | 4 | 200 | 0.05 | 99 | 300 | 146.65 ± 4.99 | 1.36 | 48.39 ± 5.40 |
| VRC IE | I-Aug-BS | Inh_2 | 0 | 5 | 200 | 0.02 | 99 | 300 | 146.07 ± 4.45 | 1.37 | 48.20 ± 4.92 |
| VRC IE | E-Aug-BS | Inh_1 | 0 | 5 | 100 | 0.03 | 99 | 300 | 84.91 ± 3.06 | 1.18 | 28.02 ± 4.41 |
| Phrenic | PSR | Ex | 0 | 3 | 50 | 0.03 | 300 | 300 | 45.92 ± 1.84 | 1.09 | 45.92 ± 6.62 |
| VRC NRM | PRG cIE | Inh_1 | 0 | 2 | 100 | 0.001 | 300 | 100 | 63.28 ± 3.18 | 1.58 | 189.84 ± 7.52 |
| VRC NRM | PRG I | Ex | 0 | 1 | 100 | 0.002 | 300 | 100 | 63.25 ± 3.00 | 1.58 | 189.74 ± 8.31 |
| VRC NRM | PRG rIE | Inh_2 | 0 | 1 | 100 | 0.002 | 300 | 100 | 63.41 ± 3.22 | 1.58 | 190.23 ± 7.92 |
| PRG cIE | I-Driver | Ex | 0 | 5 | 100 | 0.03 | 100 | 300 | 85.68 ± 2.78 | 1.17 | 28.56 ± 4.45 |
| PSR | Pump+ | Ex | 0 | 3 | 50 | 0.015 | 300 | 300 | 46.11 ± 1.76 | 1.08 | 46.11 ± 6.15 |
| PSR | Pump− | Ex | 0 | 3 | 50 | 0.015 | 300 | 300 | 46.23 ± 1.78 | 1.08 | 46.23 ± 9.43 |
| PRG EI | PRG cIE | Inh_1 | 0 | 1 | 100 | 0.05 | 100 | 100 | 63.17 ± 2.78 | 1.58 | 63.17 ± 5.11 |
| PRG EI | E-Dec-T | Ex | 0 | 5 | 100 | 0.04 | 100 | 300 | 85.12 ± 2.95 | 1.17 | 28.37 ± 4.38 |
| PRG EI | VRC IE | Ex | 0 | 1 | 50 | 0.001 | 100 | 99 | 39.21 ± 2.16 | 1.28 | 39.61 ± 3.92 |
| PRG E | PRG EI | Ex | 0 | 1 | 100 | 0.008 | 100 | 100 | 63.09 ± 2.87 | 1.59 | 63.09 ± 4.46 |
| PRG E | I-Dec | Inh_1 | 0 | 1 | 100 | 0.005 | 100 | 300 | 84.70 ± 3.14 | 1.18 | 28.23 ± 4.52 |
| PRG E | PRG rIE | Inh_1 | 0 | 1 | 100 | 0.011 | 100 | 100 | 62.86 ± 3.19 | 1.59 | 62.86 ± 5.92 |
| PRG rIE | E-Dec-P | Ex | 0 | 5 | 100 | 0.025 | 100 | 300 | 85.48 ± 2.95 | 1.17 | 28.49 ± 4.34 |
| PRG rIE | VRC IE | Ex | 0 | 1 | 100 | 0.001 | 100 | 99 | 63.13 ± 3.05 | 1.58 | 63.77 ± 5.20 |
| Pump− | PRG E | Pre | 0 | 1 | 100 | 0.95 | 300 | 100 | 63.46 ± 3.14 | 1.58 | 190.39 ± 7.82 |
| Pump− | I-Dec | Inh_1 | 0 | 2 | 25 | 0.0035 | 300 | 300 | 23.98 ± 0.90 | 1.04 | 23.98 ± 5.97 |
| Pump− | PRG I | Pre | 0 | 1 | 100 | 0.95 | 300 | 100 | 63.14 ± 3.05 | 1.58 | 189.43 ± 8.77 |
| Pump− | PRG I | Pre | 0 | 1 | 100 | 0.95 | 300 | 100 | 63.12 ± 3.16 | 1.58 | 189.37 ± 8.97 |
| Pump− | PRG rIE | Pre | 0 | 1 | 100 | 0.95 | 300 | 100 | 63.37 ± 3.06 | 1.58 | 190.12 ± 9.62 |
| Pump− | PRG rIE | Pre | 0 | 1 | 100 | 0.95 | 300 | 100 | 63.43 ± 3.01 | 1.58 | 190.28 ± 11.40 |
| Pump+ | E-Dec-P | Ex | 0 | 2 | 100 | 0.002 | 300 | 300 | 85.47 ± 2.95 | 1.17 | 85.47 ± 8.14 |
| Pump+ | VRC IE | Ex | 0 | 2 | 25 | 0.004 | 300 | 99 | 22.17 ± 1.41 | 1.13 | 67.17 ± 17.13 |
| Pump+ | I-Aug-BS | Ex | 0 | 2 | 25 | 0.002 | 300 | 300 | 24.07 ± 0.91 | 1.04 | 24.07 ± 4.15 |
| Pump+ | E-Dec-T | Ex | 0 | 2 | 100 | 0.002 | 300 | 300 | 85.12 ± 3.16 | 1.17 | 85.12 ± 6.94 |
| E-Aug-BS | Exp Motor | Ex | 0 | 5 | 200 | 0.01 | 300 | 300 | 146.21 ± 4.65 | 1.37 | 146.21 ± 9.31 |
| PRG E-Other | PRG cIE | Inh_1 | 0 | 1 | 100 | 0.001 | 100 | 100 | 63.91 ± 3.34 | 1.56 | 63.91 ± 4.69 |
| PRG I | PRG E-Other | Inh_1 | 0 | 1 | 100 | 0.05 | 100 | 100 | 63.91 ± 3.34 | 1.56 | 63.91 ± 4.69 |
| PRG I | PRG rIE | Inh_1 | 0 | 1 | 100 | 0.02 | 100 | 100 | 62.86 ± 3.19 | 1.59 | 62.86 ± 5.92 |
| PRG I | I-Aug-BS | Ex | 0 | 4 | 50 | 0.005 | 100 | 300 | 46.36 ± 1.83 | 1.08 | 15.45 ± 3.58 |
| PRG I | VRC IE | Ex | 0 | 5 | 50 | 0.007 | 100 | 99 | 39.58 ± 2.66 | 1.26 | 39.98 ± 6.47 |
| PRG NRM+ | E-Dec-P | Ex | 0 | 1 | 100 | 0.01 | 100 | 300 | 84.98 ± 3.08 | 1.18 | 28.33 ± 4.71 |
| PRG NRM+ | E-Dec-T | Ex | 0 | 1 | 100 | 0.01 | 100 | 300 | 84.86 ± 2.53 | 1.18 | 28.29 ± 4.38 |
| PRG NRM+ | I-Aug-BS | Ex | 0 | 1 | 100 | 0.01 | 100 | 300 | 84.79 ± 2.94 | 1.18 | 28.26 ± 4.55 |
| PRG NRM+ | VRC IE | Ex | 0 | 1 | 100 | 0.01 | 100 | 99 | 63.07 ± 3.05 | 1.59 | 63.71 ± 4.82 |
| PRG NRM+ | I-Driver | Ex | 0 | 5 | 100 | 0.11 | 100 | 300 | 84.79 ± 2.94 | 1.18 | 28.26 ± 4.55 |
| PRG NRM+ | E-Aug-late | Ex | 0 | 4 | 50 | 0.003 | 100 | 300 | 46.36 ± 1.83 | 1.08 | 15.45 ± 3.58 |
| PRG NRM+ | E-Aug-early | Ex | 0 | 4 | 50 | 0.003 | 100 | 300 | 46.36 ± 1.83 | 1.08 | 15.45 ± 3.58 |
| PRG NRM+ | PRG rIE | Ex | 0 | 1 | 100 | 0.015 | 100 | 100 | 62.86 ± 3.19 | 1.59 | 62.86 ± 5.92 |
| PRG NRM− | VRC NRM | Inh_1 | 0 | 1 | 100 | 0.001 | 100 | 300 | 84.68 ± 2.67 | 1.18 | 28.23 ± 4.60 |
Connections between individual neurons were made according to a sequence of pseudorandom numbers calculated from a unique seed number for each source-to-target connection. Targets were chosen with replacement. This table includes the means ± SD of the number of neurons in each target population innervated by each source neuron in each population. Corresponding values are also shown for source neurons that innervated each target neuron in each population. These data indicate the extent of divergence and convergence, respectively. Most neurons in each source population made a single terminal connection with each target neuron. Mean No. of Terminals, the mean number of terminals from each source neuron innervating each target neuron. The efficacy of connections between populations of neurons was influenced by the change in conductance associated with each action potential at a synapse (Synaptic Strength) and the number of terminals for each axon. Synaptic types were distinguished by their equilibrium potentials and time constants. The time constant of some synapses was slightly longer than others because troughs in cross-correlograms from which the particular synaptic connections were inferred tended to have longer durations. Four types of synapses were used in the first series of simulations: excitatory (Ex, equilibrium potential of 115.0 mV; time constant, 1.5 ms); type 1 inhibitory (Inh_1, equilibrium potential, − 25.0 mV; time constant, 1.5 ms); type 2 inhibitory (Inh_2, equilibrium potential, −25.0 mV; time constant, 2.0 ms); pre-synaptic modulation (Pre, time constant, 1.5 ms). If the value of the pre-synaptic modulatory strength parameter (Synaptic Strength) was <1.0, the strength of the connection it modulates was reduced to the product of the presynaptic Synaptic Strength parameter and target synapse conductance. If the presynaptic Synaptic Strength parameter was >1.0, the amount by which it was greater than 1 is added to its target synapse's conductance. Minimum and maximum conduction times, are expressed in 0.5-ms simulation clock ticks for each source-to-target axon population. No. of Terminals, number of terminals from source neuron.