The origin of spontaneous activity in developing networks of the vertebrate nervous system.

Spontaneous neuronal activity has been detected in many parts of the developing vertebrate nervous system. Recent studies suggest that this activity depends on properties that are probably shared by all developing networks. Of particular importance is the high excitability of recurrently connected, developing networks and the presence of activity-induced transient depression of network excitability. In the spinal cord, it has been proposed that the interaction of these properties gives rise to spontaneous, periodic activity.