Figure 2.

Stability of neuron–behavior relationship. A, Change in firing rate across 1000 reaches for all neuron–direction pairs for monkeys G, H, and L between first half and last half of trials, normalized to average rate. B, Shift in preferred direction between first and last half of trials. C, Linear model performance for monkey H. ρ value indicates correlation between parameters predicted using each test epoch (abscissa) and final 5 min of behavior. Neurons are sorted by ρ value in epoch 1 on the ordinate. D, Behavioral trends for repeated reaches to one target (monkey H). Red star, Statistically significant trends. E, Error between predicted and measured hand position as a function of time between model generation and test, normalized to the value closest to test set.