ONTOGENY OF CONSUMMATORY SUCCESSIVE NEGATIVE CONTRAST IN RATS

SUAREZ, A.; MUSTACA, A.; PAUTASSI, R.; KAMENETZKY, G.

DEVELOPMENTAL PSYCHOBIOLOGY

JOHN WILEY & SONS INC

Lugar: New York; Año: 2014 vol. 56 p. 989 - 998

0012-1630

Consummatory successive negative contrast (cSNC) occurs when organisms repeatedly exposed to a high-magnitude reward are suddenly given a low-magnitude reward. This results in a significant reduction in the consumption of the devalued reinforcer, at a level even below that of a group which had been always exposed to the low-magnitude reinforcer. A scarcity of animal studies assessed the expression of this phenomenon during early development. Three experiments assessed age of cSNC onset in preweanling rats. Percent body weight gained (% BWG) and taste reactions associated with reinforcement devaluation were measured. A reduction in %BWG and a significant increase in emission of aversive hedonic behaviors, indicative of cSNC, occurred on postnatal day 18 (PD 18; Experiments 1 and 2), but not on PD 14 or PD 17 (Experiments 3a and 3b). The neurobiological mechanisms underlying these effects and theoretical implications are discussed.