Sensitization refers to responses to a stimulus that become stronger with exposure. Which option best describes this?

• A. Reactions grow stronger with repeated exposure
• B. Responses diminish over time due to habituation
• C. A neutral stimulus becomes a conditioned stimulus
• D. A behavior is reinforced only with occasional rewards

Answer: (A)

Sensitization is a non-associative learning process in which responses to a stimulus become more intense with repeated exposure. As the dog encounters the stimulus again and again, arousal or neural sensitivity can increase, making the reaction larger each time. For example, a dog that is repeatedly exposed to a startling cue may startle more strongly over time rather than becoming numb to it. This is different from habituation, where responses lessen with repeated, non-threatening exposure. It’s also not about a neutral stimulus turning into a conditioned stimulus, nor about reinforcement patterns shaping behavior. So, the idea that reactions grow stronger with repeated exposure best captures sensitization.