Fig. 7
Comparison of model threshold currents for A (red), B (blue), and C (yellow) fibers with the rectangular biphasic pulse currents delivered in preclinical and clinical studies of VNS. Each panel shows the cuff geometry modeled to match the experimental setup and the lowest threshold in each nerve for each fiber type (colored x’s; legend in panel F). The experimental stimulation amplitudes are included in each panel (gray dashed lines). A (Dawson et al. 2021) delivered 0.8 mA in all patients. B (Koopman et al. 2016) delivered 1 mA in all patients in the TNF production study. C (Premchand et al. 2014) delivered 1.5–3 mA in patients (as marked) with a 2.0 ± 0.6 mA (mean ± SD). D (Baylor Research Institute 2023) delivered 0.8 mA in all patients. E (Genovese et al. 2020) delivered 0.45–2.5 mA in patients (as marked) with a 1.52 ± 0.55 mA (mean ± SD). G (Porter et al. 2012) delivered 0.8 mA in all animals. H (Kin et al. 2021) delivered different stimulation amplitudes (0.1, 0.25, 0.5, 1 mA) to each cohort of animals; 0.25 and 0.5 mA produced an anti-inflammatory effect, but 0.1 and 1 mA did not. I (Li et al. 2019) delivered 0.1–0.13 mA (as marked) in all animals