The spike arrives faster than thought. It peaks within seconds and takes many minutes to clear, and during that window the narrowed attention feels like intense focus, which is the dangerous part.
Most account-damaging sequences happen inside it. A gap against the position, a stop missed by a tick, a sudden run in your favour that turns a plan into a desire for more. In each case the decision gets made while the body is still flooded.
Build a mandatory pause into the plan for exactly these moments: hands off the keyboard, two minutes of slow breathing, then re-read the written plan before touching anything. The pause costs almost nothing and removes the trades you would most like to take back.
Related: stress-response, tilt-protocol, panic-selling, box-breathing