To position his feet correctly on the wire, tightrope walker needs precise sensory feedback. This skilled motor behaviour requires the rapid integration of external sensory input to achieve accuracy in foot placement while keeping the balance. Neurones in contact with the cerebrospinal fluid (CSF-cNs), localized around the medullo-spinal central canal in all vertebrates, are GABAergic and selectively express PKD2L1 channel (Polycystin Kidney Disease 2-like1), a member of TRP superfamily, with chemo/mechanosensitive properties. In zebrafish, CSF-cNs respond to spinal cord bending and modulate swimming behaviour, that’s why it is suggested they might represent a novel population of sensory neurones within the central nervous system. Our recent study demonstrated for the first time in mammals their involvement in the modulation of fine movements and our objective is to elucidate their contribution in shaping this motor behaviour. Using ChannelRhodopsin Assisted Circuit Mapping approach, we assessed their functional connectivity with motor interneurons, recorded with the whole-cell patch-clamp technique in lumbar spinal cord slices from PKD2L1-Cre::ChR2 mice. Their identity was then determined with the single-cell RT-PCR strategy and we finally studied the modulation by CPGRs of the neurotransmission. Our work, show that lumbar CSF-cNs form functional projections onto many cardinal interneurons involved in locomotor control. We can suggest that CSFcNs might take part in a sensory feedback loop to regulate precision movements thanks to this broad connectivity on CPG interneurons. Which in turn control motoneurons to adjust correct limb trajectories and posture.