1. When faced with a changing environment, some species appear to adapt quickly, while others seem unable to update the value of environmental cues on which they base their decisions, leading them to display seemingly maladaptive responses. 2. While behavioural and cognitive plasticity are two traits that should predict the ability of species to update the value of environmental cues, we argue that this flexibility may be constrained by ontogeny. While sensitive periods have been shown to exist for establishing an individual’s food, habitat and mate preference, no studies have established the existence of a cognitive sensitive period for predation-related information. 3. In this study, we used wood frogs, Lithobates sylvaticus, to demonstrate the existence of a sensitive period for predation-related information, with risk information learned as embryos maintained for more than 5 weeks, while the same information learned as tadpoles was unused after just 10 days. Next we demonstrated that tadpoles that had learned a cue as safe as embryos were unable to update the cue as risky after three fear conditioning attempts, while tadpoles that learned the cue as safe a few days prior did successfully update the cue as risky after three conditionings. 4. We coined the term ‘cognitive resonance’ to describe how information learned early in life can have marked cognitive consequence later in life, affecting not only the duration for which information learned is actively used in decision-making, but how this information can interfere with the acquisition of up-to-date information about the environment. 5. Cognitive resonance might be beneficial in stable environments where the change in the value of a cue is relatively small through time, but it can quickly become costly in environments where the identity of potential threats changes quickly, as in the case of introduced species.