Fig. 6: Stimulation of the motor thalamus amplifies motor outputs after CST lesions.

a Top panels: T2-weighted post-mortem MRI of IC lesion and VLL location (axial plane). (Cu: Caudate Nucleus, IC: Internal Capsule, Pt: Putamen). Bottom panels: HDFT of the CST in intact and lesioned hemispheres. Volume of cumulative CST (mean ± SE over animals) for both hemispheres normalized over the volume of the intact hemisphere. b Left panels: Example of post-lesion MEPs of one arm muscle (n = 40, BIC: Biceps, MK-JC), one hand muscle (n = 40, ECR: Extensor Communis Radialis, MK-JC), and one finger muscle (n = 40, FDM: Flexor Digitorum Minimi, MK-JC) with IC stim alone and then paired with VLL stimulation at 50 and 80 Hz. Right panels: percentage of increase of arm, hand, and finger MEPs post-lesion between IC stimulation alone and paired with VLL stimulation at 50 and 80 Hz. For each monkey, the percentage of increase was calculated over the medians and averaged over all the muscles. See Supplementary Fig. 5 for boxplots for single muscles. (***), (**), or (*) was placed if muscles in each group showed a significant increase (respective to p-values 0.001, 0.01, and 0.05). c Left panel: Example of force traces (n = 20). Right panel: boxplot of AUC pre- and post-lesion for IC alone, and IC with VLL 50 Hz and VLL 80 Hz. For all boxplots, the whiskers extend to the maximum spread not considering outliers. Central, top, and bottom lines represent median, 25th, and 75th percentile, respectively. For all (a–c), statistical significance was assessed with two-tail bootstrapping with Bonferroni correction: p < 0.05 (*), p < 0.01 (**), p < 0.001(***). Source data for (a–c) are provided as a Source Data file.