Time course of recovery of finger dexterity and brain activity.
(A) Reach and grasp. (B) The time course of precision grip success rate in monkey R. Black arrowheads indicate the days corresponding to the recordings shown in (D). The black area in the inset indicates the site of the spinal cord lesion. The percentage value beside the spinal cord illustration shows the proportion of the tissue that was lesioned. (C) Schematic drawing of simultaneous recording of SMC-ECoG and NAc-LFP. (D) Time-frequencygram of M1 (upper panels) and NAc (lower panels) activities in monkey R. Time 0, grasp onset; green arrowheads, reach onset; red arrowheads, grasp end. Each panel is the average of 30 trials. (E) Population data of mean power change compared with baseline period (–1.5 to –1.0 s from grasp onset) in M1 while the monkeys were grasping (0 to 0.5 s from grasp onset). n: The number of simultaneous recording sessions consisted of 30 trials across two monkeys (T and R) at each stage. Shading indicates the standard error of the mean (SEM). Blue points at the top of the graph: P < 0.05, one-way analysis of variance. See the methods. (F) Same as (E) but in the NAc.