INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
ROLE OF CONTEXT IN THE EXTINCTION PARADIGM IN PREWEANLING RATS
Autor/es:
REVILLO, D.A.; TREBUCQ, G; PAGLINI, M.G.; ARIAS, C.
Reunión:
Congreso; XXVII Congreso de la Sociedad Española de Psicologia Comparada; 2015
Resumen:
While Pavlovian extinction has been widely studied in adult organisms, only few studies have focused on this effect during infancy. Although it is currently accepted that the extinction effect reflects new ?context-dependent- learning, this is not so clear during infancy, because some studies did not find recovery of the extinguished CR before postnatal day (PD) 21. The authors concluded that extinction during infancy erases the CS-US association. However, we have recently reported evidences of renewal, more rapid reacquisition, reinstatement and spontaneous recovery of an extinguished CR in preweanling rats. The present study analyzed the possibility of recovering an extinguished CR with a reinstatement procedure in a fear conditioning paradigm, on PD17 (Experiment 1-4) and on PD23 (Experiment 5). At the same time, it was explored the role of context salience as a procedural variable that may affect extinction during the preweanling period. In accordance with previous studies form our laboratory, results shown that preweanling rats expressed a previously extinguished CR after a single experience with an unsignaled US (Experiments 2 and 4a). Furthermore, this result was only found when subjects were trained and tested in salient contexts, but not in standard ones (Experiments 3 and 4b). Finally, Experiment 5 demonstrated the reinstatement effect on PD23 in a standard context. These results are in agreement with previous findings showing that the extinction effect during infancy shares features with extinction learning in adult organisms.