Extended Data Fig. 3: Neuronal population trajectories in PC-space have lower tangling than the corresponding motor nerve trajectories.
From: Movement is governed by rotational neural dynamics in spinal motor networks
a, Illustration that during rotational dynamics the points in the trajectory that move in opposite direction are also far apart, i.e. they have low tangling (left), whereas during alternation the points of the trajectory that move in opposite direction are also close, i.e. have high tangling (right). b, The ratio of tangling metric of the PC trajectory of the nerves (Qnerve) to that of the network (Qnetwork). This ratio is close to 100%, which indicates most trials and animals had a larger tangling of the motor nerves than the network. (N = 11, data set 1; N = 10, data set 2; N = 10, data set 3; N = 4, data set 4; N = 3, data set 5). c–g, Sample trials from 5 different data sets. Left is shown the phase sorted firing rate activity (top) and the associated nerves (bottom). The nerves were rectified and low-pass filtered (red) on temporal scale matching the firing rates. The PCs of network (middle left) and nerves (middle right, green). Scales of PCs are variance normalized. The tangling metric (Q) for the nerve PCs (in 3 dimensions) is calculated as a function of time (t) through the trial and plotted versus that for the network. The ratio of points below the x = y–line (pale blue) is indicated in percent and form one point in panel (b). Note that the nerve trajectories more resemble "alternation" whereas the network more resembles "rotation"-scheme of (a).
