TY - JOUR T1 - The Critical Role of Locomotion Mechanics in Decoding Sensory Systems JF - The Journal of Neuroscience JO - J. Neurosci. SP - 1123 LP - 1128 DO - 10.1523/JNEUROSCI.4198-06.2007 VL - 27 IS - 5 AU - Noah J. Cowan AU - Eric S. Fortune Y1 - 2007/01/31 UR - http://www.jneurosci.org/content/27/5/1123.abstract N2 - How do neural systems process sensory information to control locomotion? The weakly electric knifefish Eigenmannia, an ideal model for studying sensorimotor control, swims to stabilize the sensory image of a sinusoidally moving refuge. Tracking performance is best at stimulus frequencies less than ∼1 Hz. Kinematic analysis, which is widely used in the study of neural control of movement, predicts commensurately low-pass sensory processing for control. The inclusion of Newtonian mechanics in the analysis of the behavior, however, categorically shifts the prediction: this analysis predicts that sensory processing is high pass. The counterintuitive prediction that a low-pass behavior is controlled by a high-pass neural filter nevertheless matches previously reported but poorly understood high-pass filtering seen in electrosensory afferents and downstream neurons. Furthermore, a model incorporating the high-pass controller matches animal behavior, whereas the model with the low-pass controller does not and is unstable. Because locomotor mechanics are similar in a wide array of animals, these data suggest that such high-pass sensory filters may be a general mechanism used for task-level locomotion control. Furthermore, these data highlight the critical role of mechanical analyses in addition to widely used kinematic analyses in the study of neural control systems. ER -