Cover legend: During rhythmic motor patterns, a premotor network in the spinal cord provides balanced excitation (gray traces) and inhibition (white traces) to motoneurons (stained green in image) located in the ventral horns. The membrane potential of a single recorded motoneuron is shown in the red trace and hip flexor activity is shown in the green trace. Cell nuclei, many from spinal interneurons, are stained blue (DAPI). For more information, see the article by Petersen et al. (pages 2774–2784).