Fig 5. Computational modeling of the time course of PAS₁ and PAS₂ effects.

MEP amplitudes as a function of time modeled from the experimental MEP raw data independently for PAS₁ and PAS₂ at all IPIs. PAS₁ and PAS₂ model functions, i.e. the time course of MEP amplitude changes after PAS₁ vs. those after PAS₂, were significantly different at all IPIs (P < 0.0001 each). In addition, PAS₂ effects at IPI₁₀ and IPI₃₀ were significantly different from PAS₂ effects at IPI₆₀ and IPI₁₈₀ (P < 0.0001), and PAS₂ effects at IPI₁₀ from PAS₂ effects at IPI₃₀ (P = 0.033), but not PAS₂ effects at IPI₆₀ from those at IPI₁₈₀ (P > 0.5). Experimental data are shown as mean ± SEM. Note that data for PAS₂ at time points 60min and 180min post PAS₂ are from six subjects only, whereas all other data are from twelve subjects (see Material and Methods). Y-axis, logarithmic scaling.