When a person is frightened, the excited sympathetic nervous system can cause the pupils to dilate to their maximum extent in less than a second.
During the core fear response period, this extreme dilation of the pupils will last for 1-5 seconds, indicating that the body is in a state of high alert, ready to respond to potential threats.
Even after the initial peak of fright has passed, the pupils may not immediately return to baseline levels. If the [source of fear] persists, or if the individual remains in a constant state of tension and anxiety, the pupils may remain dilated to some extent for tens of seconds or even minutes.
In Nan Zhubin's eyes, the visitor is currently in this state of sustained fright.
The visitor's pupils, after being extremely dilated, have not returned to the baseline for a long time, accompanied by reactions such as staring eyes, fixed gaze, stiff and trembling body, sitting motionless on the sofa and gasping.
