The reality that stress increases your sensitivity to faint pain stimuli is important to a student's understanding of signal detection theory
place theory
frequency theory
opponent process theory
placebo theory

signal detection theory

Explanation:

Signal detection theory is the concept of using the intensity of a stimuli to detect the intensity and psychological state of a person.

Therefore, the reality that stress increases sensitivity to faint pain stimuli is important to a student's understanding of signal detection theory because attention is called to things based on their intensity.