Figure 1. Task design, implantation, and behavior. a, Illustration of a monkey in the experimental setup. The cues were presented on a masked monitor and reflected by a mirror such that cues appeared superimposed on the grasping handle. b, Delayed grasping task with two grip types (top, power grip; bottom, precision grip). Trials were presented in pseudorandom order in darkness and with the handle in the upright position. c, d, Plots of RT and MT against delay length for all successful trials of both monkeys. Boxes represent the median and 25th/75th percentiles for each delay bin, while whiskers mark ∼±2.7 SDs. Outliers are shown as individual points. e, f, Array locations for Monkeys S (e) and B (f). Two arrays were placed in F5 on the bank of the arcuate sulcus (AS) and two were placed in the AIP toward the lateral end of the intraparietal sulcus (IPS). In Monkey B two more arrays were placed on the bank of the central sulcus (CS). These were not used in this study. The cross shows medial (M), lateral (L), anterior (A), and posterior (P) directions. Note that Monkey S was implanted in the left hemisphere and Monkey B was implanted in the right hemisphere.