Context‐dependent latent inhibition in preweanling rats

Abstract

Preexposure to a conditioned stimulus (CS) usually weakens conditioning, an effect known as latent inhibition. Similar to other learning interference effects, latent inhibition has been characterized as context-dependent, which means that the magnitude of this effect can be attenuated by changing the context between the different phases of the procedure (e.g., preexposure and conditioning). Latent inhibition has been found with a variety of procedures in infant rats, but the few studies that examined the context-dependency of this phenomenon during this ontogenetic period found no context-change effect. The present study explored the context-dependency of latent inhibition during infancy using a conditioned taste aversion preparation and employing contexts enriched with distinctive odors to increase the possible efficacy of the context manipulation. Experiment 1 showed that three preexposures to the CS (saccharin) were sufficient to retard conditioning to the same CS, although this effect was also observed in a control group preexposed to an alternative taste stimulus (saline), in comparison with a non-preexposed control group. In Experiment 2a, the CS-preexposure effect was found to be specific to the preexposed CS when the number of preexposures was increased. This effect was revealed as context-dependent in Experiment 2b, since it was attenuated by changing the context between preexposure and conditioning. The present result is consistent with recent studies showing the context-dependency of extinction in preweanling rats, thus demonstrating these animals' capacity to learn about context early on in their development.

Cortico-Hippocampal Computational Modeling Using Quantum Neural Networks to Simulate Classical Conditioning Paradigms

“…Lesioning the model did not affect the output CR of the second phase after the pre-exposure at the beginning, as shown in Figure 23 . All of these results were confirmed experimentally by [ 58 , 59 , 60 ].…”

Long-term contextual memory in infant rats as evidenced by an ethanol conditioned tolerance procedure

“…In agreement with these results, some studies have found contextdependent interference learning in 23-day-old rats, but not in younger pre-weanlings (around PD 17), leading to the conclusion that the context does not influence interference learning during infancy (Kim and Richardson, 2010). However, other studies have recently reported clear evidences of context-dependent interference effects (for example, Revillo et al, 2013, Revillo et al, 2014, context learning (Ramsaran, Westbrook and Stanton, 2016) and Pavlovian contextual conditioning in pre-weanling rats (for example, Pugh and Rudy, 1996, Brasser and Spear, 1998, Park, Ganella and Kim, 2017Pisano et al, 2012). In fact, under particular conditions, contextual memory is even greater in infants than in adult rats (Brasser and Spear, 2004).…”

Context‐dependent extinction of an appetitive operant conditioned response in infant rats

“…Subtle changes in task parameters can lead to important differences in performance, particularly at early stages of development during which rapid maturational changes occur. For instance, the sensory content of the context seems to be critical for some context effects during infancy, facilitating not only direct context conditioning (Brasser & Spear, 2004;Pugh & Rudy, 1996), but also interference effects (Revillo, Gaztanaga, et al, 2014, Revillo, Trebucq, et al, 2016. Interestingly, this and other studies demonstrating ABArenewal in preweaning rats included salient odors in the testing context (Revillo, Molina, et al, 2013, Revillo, Castelló et al, 2014, Revillo, Cotella, et al, 2015.…”