When we are moving, motor circuits in the spinal cord are constantly being barraged by information from sensory receptors in the skin and muscles, telling these circuits what our limbs are doing or what the ground underfoot feels like.
Cells in the dorsal spinal cord (the back) receive sensory information from the body and then pass it on to neurons in the ventral part of the spinal cord (the front) that generate coordinated movement.
“I think what’s really exciting about this project is that we managed to isolate and describe this very local and very specific circuit, which is only active during stepping,” says Stephanie Koch, a Salk research associate and first author of the paper.
Salk Institute scientists have solved a longstanding mystery about how our spinal cord knows when to pay attention to certain pieces of information, and when to ignore it as distracting from the task at hand.
The work, appearing in the journal Neuron on December 7, 2017, reveals that specific neurons called RORbeta (RORβ) interneurons inhibit transmission of potentially disruptive sensory information during walking in order to promote a fluid gait. The research illustrates a high level of sophistication in spinal cord information processing.