The child is now operating as if it was under extreme threat. In otherwords, the child is experiencing a strong chemical need to survive. The child has an uncontrollable chemically driven desire to get away, but, there is nothing tangible to get away from. An organic need to continually check the environment to ensure safety. Rules no can no longer be recalled, cognitive restrictions do not apply.
Emotions are running high, energy is at a surplus.
The environment has lit the fuse of that particular developmental delay and the reflexive firework has exploded into the faces of everyone who is around at the time. Let us look at a slightly different scenario. Instead of being active in this environment, the child is passive. Sitting quietly, breathing shallowly. Now the result is the opposite.