Psychologists fail to replicate well-known behaviour linked to learning

Physiologist Ivan Pavlov conditioned dogs to associate food with the sound of a buzzer, which left them salivating. Decades later, researchers discovered such training appears to block efforts to teach the animals to link other stimuli to the same reward. Dogs trained to expect food when a buzzer sounds can then be conditioned to salivate when they are exposed to the noise and a flash of light simultaneously. But light alone will not cue them to drool.
Read more: http://www.nature.com/news/psychologists-fail-to-replicate-well-known-behaviour-linked-to-learning-1.20659?source=Snapzu