Neural mechanism of optimal limb coordination in crustacean swimming

• DOI: 10.1073/pnas.1323208111
• Publication Date: 2014-09-09T04:38:33Z
• Authors: Calvin Zhang; Robert D. Guy; Brian Mulloney; Qinghai Zhang; Timothy J. Lewis
• Keywords: Biological neural network; Simplicity

A fundamental challenge in neuroscience is to understand how biologically salient motor behaviors emerge from properties of the underlying neural circuits. Crayfish, krill, prawns, lobsters, and other long-tailed crustaceans swim by rhythmically moving limbs called swimmerets. Over entire biological range animal size paddling frequency, movements adjacent swimmerets maintain an approximate quarter-period phase difference with more posterior leading cycle. We use a computational fluid dynamics model show that this frequency-invariant stroke pattern most effective mechanically efficient rhythm across full relevant Reynolds numbers crustacean swimming. then organization circuit swimmeret coordination provides robust mechanism for generating pattern. Specifically, wave-like limb emerges robustly combination half-center structure local central circuits (CPGs) drive each limb, asymmetric network topology connections between CPGs, response which we measure experimentally. Thus, system serves as concrete example architecture leads optimal behavior manner. Furthermore, consider all possible connection topologies CPGs natural connectivity generates biomechanically robustly. Given high metabolic cost swimming, our results suggest selection has pushed toward produces behavior.