“…The details of synaptic connectivity responsible for this phenomenon have been substantially explored in the lamprey (Wallén and Grillner, 1987; Grillner et al, 2001; Grillner, 2006) and the Xenopus embryo (Dale and Roberts, 1984, 1985). More recently, work in higher vertebrates (Masino et al, 2012) has emphasized how well conserved this network motif is throughout the vertebrate subphylum including lampreys, fishes, amphibians, chelonids and mammals (Dale and Roberts, 1984; Sigvardt et al, 1985; Kudo and Yamada, 1987; Hernandez et al, 1991; Guertin and Hounsgaard, 1998; Gabriel et al, 2009; Masino et al, 2012). After complete spinal transection (Cohen and Wallén, 1980; Brodin et al, 1985), the lamprey swimming network can still generate the electrophysiological correlates of swimming.…”