FIGURE 5.4 Classically Conditioned Drug Effects: Does Just the Smell of a Starbucks Espresso Perk You Up? If it does, classical conditioning is at work! Pavlov (1927) suggested that administering a drug could be viewed as a conditioning trial. Just like pairing the sound of a bell with the presentation of food, if specific environmental cues are repeatedly paired with a drug’s administration, they can become conditioned stimuli that eventually elicit the drug’s effect. For a regular coffee drinker, the sight, smell, and taste of freshly brewed coffee are the original neutral stimuli that, after being repeatedly paired with caffeine (the UCS), eventually become conditioned stimuli, producing the CR: increased arousal and alertness.