t = 0.0 s
This simulation models the acute stress response triggered by a sudden fright. A schematic human figure shows the organs targeted by circulating adrenaline — heart, eyes, lungs, gut, liver and skeletal muscle — responding in real time after the sympathetic nervous system signals the adrenal medulla to release epinephrine into the bloodstream. Heart rate and pupil dilation react within seconds, blood flow redirects from the gut toward the muscles, breathing quickens, and the liver raises blood glucose through glycogenolysis — all real, measurable physiology. Adjust the fright intensity to change the size of the surge and the time-speed slider to watch the full multi-minute recovery play out quickly, while the relative order of response and recovery stays true to real adrenaline kinetics: heart rate and pupils move first and settle soonest, blood glucose lags and lingers longest.