A sensory-enhanced context allows renewal after extinction in the infant rat

REVILLO DAMIÁN; CASTELLÓ STEFANÍA; PAGLINI MARÍA GABRIELA; ARIAS CARLOS

San Sebastian

Congreso; XXV International Congress of the Spanish Society for Comparative Psychology. San Sebastián, España; 2013

A sensory-enhanced context allows renewal after extinction in the infant rat. Damian Revillo1,2, Stefania Castello1,2, M. Gabriela Paglini1, & Carlos Arias3. 1Instituto Mercedes & Martin Ferreyra (INIMEC-CONICET-UNC), 2Universidad Nacional de Cordoba, 3Universidad del Pais Vasco (UPV/EHU) Empirical studies of extinction in preweanling rats have failed to find ABA-renewal in a fear-conditioning paradigm. This result supports the hypothesis postulating ontogenetic qualitative differences in experimental extinction. A similar result in adult rats led to the conclusion that ABA-renewal requires contexts A and B to differ in several types of features, including odor cues. In a recent study, we found renewal of an extinguished taste aversion response in infant rats, employing contexts, which differ in their odor content. Recently, we examined the possibility of renewing an extinguished fear response in infant rats when contexts A and B did not include or included an explicit odor. Results indicated absence of renewal when using standard contexts (without explicit odors). However, when contexts A and B varied also in their odor content, the ABA-renewal procedure was effective in reinstating the extinguished CR. These results challenge the understanding of extinction as a learning process that is qualitatively different in preweanling rats than in later stages of ontogeny. These results are in agreement with previous findings, which highlight the importance of the sensory content of the context in context learning in the infant rat