The present study evaluated context-dependent learning under an operant conditioning procedure in infant rats. Preweanling rats were trained in context A during postnatal days (PDs) 16 and 17 to learn an appetitive operant conditioning task, employing milk chocolate as appetitive reinforcer. On PD18 the operant response was extinguished in context A, or in an alternative context B. The change from context A to B between acquisition and extinction did not affect the number of responses during extinction, but slightly modified the shape of the extinction curve. On PD19, a renewal test conducted in context A clearly showed ABA-renewal of the extinguished operant response. These results add to the body of evidence indicating that infants are able to acquire and retain contextual information, and support the notion that extinction during this ontogenetic period involves new learning.
It is frequently assumed that infants are impaired in contextual memory and consequently, in recovery from extinction, a phenomenon considered to be context dependent. However, the evidence in the field is far from consistent with this interpretation, since several studies have shown context-dependent extinction in infant rats using a variety of procedures and behavioral measures. This discussion has primarily been based on studies using Pavlovian conditioning tasks. Three experiments were conducted to study reinstatement of an extinguished operant response and additionally to evaluate the context dependence of such an effect. Preweanling rats were trained on postnatal days (PDs) 16 and 17 to acquire an appetitive operant response using chocolate milk as reinforcer. At PD18 the operant response was extinguished and at PD19 animals received a reminder in the same (Experiment 1 and 2) or in a different context than the one used during the extinction phase (Experiment 3). Infant rats showed recovery from extinction after a reminder treatment (Experiments 2 and 3). This effect was dependent on the context in which the reminder was delivered (Experiment 3). Our results indicate that infant rats can recover an extinguished operant response by means of a reminder treatment in a context-dependent way, highlighting the importance of the context for modulating learning processes during infancy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.