Load signalling by cockroach trochanteral campaniform sensilla.

A major problem in sensory motor integration is to delineate how forces acting upon a leg are encoded and regulated in the control of posture and locomotion. We have studied responses of the trochanteral campaniform sensilla, the largest array of force detecting mechanoreceptors in the cockroach leg. Afferents from two groups of sensilla (Groups 3 and 4) encode forces applied to the leg in the plane of joint movement of the coxo-trochanteral joint. The receptors within Group 3 exhibit fixed patterns of recruitment that could differentially indicate when force levels are adequate to provide support and propulsion during walking.