When children feel their life is threatened, they enter a state of rigidity where the prefrontal cortex and limbic system are suppressed, relying on the primitive brainstem for basic functions like breathing and digestion. This state is marked by lack of communication, inability to think or make decisions, and heightened physical sensations that impair interaction and safety. It"s a natural response to perceived danger, affecting both adults and children, and highlights the importance of understanding and supporting individuals in these vulnerable states.