On the electrodetection threshold of aquatic vertebrates with ampullary or mucous gland electroreceptor organs.

Reinterpretation of research on the electric sense in aquatic organisms with ampullary organs results in the following conclusions. The detection limit of limnic vertebrates with ampullary organs is 1 microV cm(-1), and of marine fish is 20 nV cm(-1). Angular movements are essential for stimulation of the ampullary system in uniform d.

Evidence for transmitter operated electrical synapses (TOES) in ampullary electroreceptor organs.

Afferent fibres of ampullary electroreceptor organs in electrosensitive fish fire spontaneously, that is, they fire without external stimulus. In the past it has been postulated that the spontaneous activity originates from a sustained level of neurotransmitter release delivered by the electroreceptor cells. The spontaneous activity can be modulated by electrical stimuli.