Transient visual responses reset the phase of low-frequency oscillations in the skeletomotor periphery.

Daniel K Wood, Brain and Mind Institute, University of Western Ontario, London, ON, Canada & Department of Neurobiology, Northwestern University, 2205 Tech Dr., Hogan 2-160, Evanston, IL, 60208, USA
Chao Gu, Brain and Mind Institute, University of Western Ontario, London, ON, Canada & Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada & Robarts Research Institute, London, ON, Canada
Brian D Corneil, Brain and Mind Institute, University of Western Ontario, London, ON, Canada & Robarts Research Institute, London, ON, Canada & Departments of Psychology, Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
Paul L Gribble, Brain and Mind Institute, University of Western Ontario, London, ON, Canada & Departments of Psychology, Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
Melvyn A Goodale, Brain and Mind Institute, University of Western Ontario, London, ON, Canada & Departments of Psychology, Physiology and Pharmacology, University of Western Ontario, London, ON, Canada

Abstract

We recorded muscle activity from an upper limb muscle while human subjects reached towards peripheral targets. We tested the hypothesis that the transient visual response sweeps not only through the central nervous system, but also through the peripheral nervous system. Like the transient visual response in the central nervous system, stimulus-locked muscle responses (< 100 ms) were sensitive to stimulus contrast, and were temporally and spatially dissociable from voluntary orienting activity. Also, the arrival of visual responses reduced the variability of muscle activity by resetting the phase of ongoing low-frequency oscillations. This latter finding critically extends the emerging evidence that the feedforward visual sweep reduces neural variability via phase resetting. We conclude that, when sensory information is relevant to a particular effector, detailed information about the sensorimotor transformation, even from the earliest stages, is found in the peripheral nervous system.