A converging circuit is one of several neuronal circuits in the body, and it has a number of presynaptic neurons that stimulate one postsynaptic neuron. For example, a motor neuron receives information from many brain regions to perform a certain action.
Diverging circuits are another type of neuronal circuit in the nervous system, and these comprise one presynaptic neuron that works to stimulate a number of postsynaptic neurons, essentially the opposite of a converging circuit. One example of this is when a single sensory signal arrives at the brain then gets reactions from several regions.
An oscillating circuit is also a neuronal circuit, and in this case, the circuit stimulates a single presynaptic neuron, causing a number of postsynaptic impulses. This helps the body perform actions that require coordinated muscle movements, such as breathing.
Another neuronal circuit, a parallel after-discharge circuit, has a single presynaptic neuron that stimulates other neurons. Each of these neurons end on a single postsynaptic neuron. This action sends a number of quick impulses through the system at one time.
As of 2015, it is a consideration that these neuronal circuits, when acting abnormally, may cause epilepsy. This is a condition where neuronal discharges in the brain are not normal, leading to uncontrolled seizures and muscle movements.