Campaniform sensilla

Campaniform sensilla are a class of mechanoreceptors found in insects, which respond to stress and strain within the animal's cuticle. Campaniform sensilla function as proprioceptors that detect mechanical load as resistance to muscle contraction, similar to mammalian Golgi tendon organs. Each campaniform sensillum consists of a flexible dome, which is surrounded by a socket within the cuticle. The dendrites of a single sensory neuron innervate each sensillum. Deformation of the dome opens mechanotransduction channels in the sensory neuron, which leads to the firing of action potentials that are transmitted to the central nervous system. Campaniform sensilla are a class of mechanoreceptors found in insects, which respond to stress and strain within the animal's cuticle. Campaniform sensilla function as proprioceptors that detect mechanical load as resistance to muscle contraction, similar to mammalian Golgi tendon organs. Each campaniform sensillum consists of a flexible dome, which is surrounded by a socket within the cuticle. The dendrites of a single sensory neuron innervate each sensillum. Deformation of the dome opens mechanotransduction channels in the sensory neuron, which leads to the firing of action potentials that are transmitted to the central nervous system. Campaniform sensilla are distributed across the body surface of many insects. For example, a blowfly possesses more than 1200 campaniform sensilla, which are heavily concentrated at joints in the cuticle, including on the legs, antennae, and wings. The highest density of campaniform sensilla on the fly is found at the base of the modified hind-wings, or halteres, which function as gyroscopic sensors of self-motion during flight. The activity of campaniform sensilla was first recorded by John William Sutton Pringle, who also determined that the elliptical shape of many sensilla makes them directionally selective. Campaniform sensilla signal the magnitude of load and the rate of load change. Sensory feedback from campaniform sensilla is integrated in the control of posture and locomotion. In walking control, sensory feedback from leg campaniform sensilla is thought to reinforce muscle activity during the stance phase and to contribute to inter-leg coordination. In flight control, sensory feedback from haltere and wing campaniform sensilla is thought to mediate compensatory reflexes to maintain equilibrium.