Brenda has learned to take an over-the-counter medication 30 minutes before she eats a spicy meal. when she does this she is able to prevent the heartburn and indigestion that she would experience otherwise. this is an example of

This is avoidance conditioning. Brenda has been able to successfully link the over-the-counter heartburn medicine to an avoidance of discomfort. By taking the pill, she has received a negative reinforcement due to the removal of the indigestion. The reinforcement will likely lead to Brenda continuing to take the medicine until she habituates to it and does not receive the same benefit(s).