RT Book, Section A1 Kandel, Eric R. A1 Koester, John D. A1 Mack, Sarah H. A1 Siegelbaum, Steven A. SR Print(0) ID 1180643350 T1 Locomotion T2 Principles of Neural Science, 6e YR 2021 FD 2021 PB McGraw Hill PP New York, NY SN 9781259642234 LK neurology.mhmedical.com/content.aspx?aid=1180643350 RD 2024/03/29 AB LOCOMOTION IS ONE OF THE MOST FUNDAMENTAL of animal behaviors and is common to all members of the animal kingdom. As one might expect of such an essential behavior, the neural mechanisms responsible for the basic alternating rhythmicity that underlies locomotion are highly conserved throughout the animal kingdom, from invertebrates to vertebrates, and from the early vertebrates to primates. However, while the basic locomotor-generating circuits have been conserved, the evolution of limbs, and then of ever more complex patterns of behavior, has resulted in the development of progressively more complex spinal and supraspinal circuits (Figure 33–1).