Which of the following physiologic changes is NOT associated with the immediate stress response?

The correct choice indicates that decreased blood glucose is not associated with the immediate stress response. During an immediate stress response, the body activates the "fight or flight" mechanism, which causes a surge of stress hormones like adrenaline and cortisol. These hormones lead to an increase in heart rate and respiratory rate, diversion of blood flow to essential organs, and an elevation in blood glucose levels to provide immediate energy for the body.

When faced with stress, the body needs fuel to deal with the situation, and therefore, glucose levels rise rather than decrease. The increase in blood glucose is crucial for meeting the heightened energy demands associated with acute stress. Additionally, pain perception can change as a protective mechanism, allowing an individual to respond more quickly to a potentially harmful situation. This explains why the other physiological changes listed are consistent with the stress response while decreased blood glucose is not.