FIGURE 4.

Effect of anisomycin injection in M1 on the performance of internally generated sequential movements. (A) Sequence 1-2-4 of the repeating task. (B) Intracortical stimulation map of a Cebus monkey. Letters indicate the movements evoked at each site. S, shoulder; E, elbow; W, wrist; D, digit. Injections were done at sites in which intracortical stimulation evoked shoulder or elbow movements (i.e., arm representation). (C) Reaching end points of trials from target 2 to target 4 before and after anisomycin injection. Left: pre-injection; right: post-injection. Top: random task; bottom: repeating task. The monkey was performing sequence 1-2-4 during the repeating task. E_A: accuracy errors, a reach performed in the correct direction (e.g., to the right), but to an end point outside of the correct target; E_D: direction errors, a reach performed in the direction opposite to the correct target. Gray dots: correct response; black dots: error response. The percentages of trials ending in each target are given below the targets. *p < 0.05. (D) Averaged error rates of six injection sessions in the random task (left) and the repeating task (right). After anisomycin injection, the number of errors increased dramatically in the repeating task, but not in the random task (modified from Ohbayashi, 2020).