graded potential The size(amplitude) of the subthreshold potential is directly proportional to the strength of the triggering event. A subthreshold potential can be either hyperpolarizing(make membrane potential more negative)or depolarizing(make membrane potential more positive)• The size (amplitude) of the subthreshold potential is directly proportional to the strength of the triggering event. • A subthreshold potential can be either hyperpolarizing (make membrane potential more negative) or depolarizing (make membrane potential more positive) ➢ graded potential