"Reinforcement learning is learning what to do – how to map situations to actions – so as to maximize a numerical reward signal. The learner is not told which actions to take, as in most forms of machine learning, but instead must discover which actions yield the most reward by trying them." – Sutton, Richard S. and Andrew G. Barto. Reinforcement Learning: An Introduction. (1.1). MIT Press, Cambridge, MA, 1998.
The applications of this intervention are two-fold: first, as a diagnostic tool -- if injection increases the performance, we may conclude that an agent's network was losing its plasticity.
In fact, the interaction of these two aspects requires addressing the fact that each agent's own safety constraint requires information from all others.