A comparison of chemical and electrical synaptic transmission between single sensory cells and a motoneurone in the central nervous system of the leech

In leech ganglia, three sensory cells of different modality converge on a motoneurone, where they form chemical and electrical synapses. Each of these synapses behaves in a characteristic manner and the nature of the transmission mechanism has significant functional consequences for the operation of the reflexes. An analysis has been made of the effects of trains of impulses on synaptic transmission through these pathways, using frequencies that correspond to natural firing.