VPB 121: Veterinary Physiology - II (2+1)

PROPERTIES OF POLYSYNAPTIC ARCS 

• Series synaptic reflex arcs: Several simple reflex arcs are united in series to give a chain of reflex arcs, e.g. flexor and extensor responses related to muscle tone.
• Convergent effector reflex arcs: Two or more afferent neurons are in synaptic relation with only one efferent neuron. Hence, stimulation of many receptors  converges to excite a single effector.
• Divergent effector reflex arc: One afferent neuron is synaptic connection with two or more efferent neuron. Stimulation of a single receptor diverge through many neurons to excite more than one effector
• Internuncial reflex arcs: Two or more afferent neurons are connected with two or more effectors. Stimulation of either of the two receptors causes reflex response in one or both effectors. The connections are established through interneuonrs. It provides reciprocal excitation and inhibition for smooth co-ordinated activity.