Fig. 3.

“Three-arrow” (circuitry-based) model. A: model schematic. Each circle represents a neural population. Meth-sensitive populations (“Meth”-labeled arrows) are modeled as an artificial neuron with sigmoidal activation function applied to its input (see text for a detailed description). Circuitry is a compilation of data from the literature. Exc, excitatory; Inhib, inhibitory; HD, high dose; Mdl, medulla; SPN, sympathetic preganglionic (or premotor) neuron; TEMP, temperature. B: activation functions of Meth-sensitive populations. Vertical lines show half-activation concentrations. C: reconstructed activity of neuronal populations included in the model, together with comparison of reconstructed dynamics of body temperature, after various doses of Meth, with actual experimental data used in fitting procedures. All reconstructed values of body temperature were within 1 SD of actual experimental data within the time period used for fitting procedures (220 min, gray bar). au, Arbitrary units.