Sigmoidal fitting of recruitment curves of motor evoked potentials (MEP). Upper panels: Ab Ctrl, middle panels: Ab CA, lower panels: Ab SPS. Left panels: Ringer's. Right panels: BFA. Amplitudes are expressed in mV. Dash: 95% prediction band, dotted: 95% confidence band, p < 0.01 for each side. R2 value > 0.970 (p < 0.005).