Control Theory of Flashback Suppression via Stimulus Derivative

Flashbacks represent one of the most severe forms of stress amplification, commonly ob- served in trauma-related psychological and social phenomena. In this paper, we extend the Stress–Forgetting–Shielding (SFS) framework by interpreting flashbacks as a negative forget- ting velocity, corresponding to a rapid reduction in psychological distance. We demonstrate that, even under flashback conditions, stress amplification can be mitigated by controlling the temporal derivative of stimulus intensity. This establishes a control-theoretic principle for flash- back suppression applicable to individual, social, and collective systems.