Ring's approach

Ring [20] also proposes a method for bridging long time lags. Whenever a unit in his network receives conflicting error signals, that is, certain error signals suggest to increase the unit's activity while others suggest otherwise, he adds a higher order unit influencing appropriate connections. Although his approach can sometimes be extremely fast, to bridge a time lag involving 100 steps may require the addition of 100 units. Also, Ring's net does not generalize to unseen lag durations.