Clicker training, a method rooted in positive reinforcement, is widely regarded as one of the most welfare-friendly approaches to teaching new behaviors in dogs. However, trainers differ in how consistently they pair the click with a reward. Some recommend rewarding every click, while others suggest that occasionally omitting rewards may accelerate learning by enhancing motivation. This study tested those claims.
Published in Animal Cognition, the research by Giulia Cimarelli and colleagues from the Messerli Research Institute trained two groups of naïve dogs using clicker methods. One group received food after every click, while the other group was only rewarded 60% of the time. Researchers measured both learning speed and emotional state through a cognitive bias test that assessed optimism or pessimism in the dogs’ expectations.
The results showed that partial rewarding did not improve training efficiency. Both groups reached learning criteria in similar numbers of trials. However, the partially rewarded dogs displayed a more pessimistic bias, approaching ambiguous cues less readily, suggesting they were less optimistic or more frustrated. Dogs with higher emotional reactivity also showed stronger pessimistic tendencies, indicating individual variation in response to training methods.
These findings provide important welfare insights. While positive reinforcement remains effective, inconsistency in reward delivery may undermine emotional stability. Trainers and owners are encouraged to maintain clear, consistent reinforcement schedules to promote both learning success and positive affective states in dogs.
Source: Cimarelli, G., Schoesswender, J., Vitiello, R., Huber, L., & Virányi, Z. (2020). Partial rewarding during clicker training does not improve naïve dogs’ learning speed and induces a pessimistic-like affective state. Animal Cognition, 24, 107–119. Published September 8, 2020.
