Kinematic reconstruction: A: Flow diagram for reconstruction of the forelimb kinematics from the neural signals. B: Reconstruction of forelimb kinematics (hand x- and y-positions, elbow angle, and hand velocity) during a representative reaching trial in R1. Traces in red are the actual kinematics measured from the video images and the blue traces are the reconstructed versions obtained by linear regression. The vertical axes are the actual distances (x- and y-positions) and the elbow angle calculated from the video images. Both neural and kinematic signals are low-pass filtered with a 4th order Butterworth filter with a 12 Hz corner frequency. C: Average correlation ( R2) values for the kinematic variables reconstructed from all trials in all four animals.