Changes in sucrose and quinine taste reactivity patterns in infant rat pups after exposure to the other tastant.

The taste reactivity test is considered as an objective measure to assess the hedonic impact of tastes. Both the appetitive and aversive pattern of responses are plastic and can change based on previous experience. The present study assessed the repertoire of taste responses elicited by sucrose and quinine in preweanling rats, and described changes in these taste reactivity patterns after exposure to the other tastant. We exposed infant rats (17 days old at the start of training) to sweet (2% sucrose) or bitter (0.01% quinine) tastants during 4, 10-min trials in two different random sequences. The subjects were weighed before and after each trial to provide a measure of percent body weight gained. The following taste reactivity responses were registered: duration of mouthing and paw lick, frequency of chin rub, head shake and flailing of the forelimbs, frequency and duration of face washing, wall climbing and paw tread. The consummatory and affective taste responses changed depending on the order in which the solutions were administered. The order of exposure to the tastants did not affect the levels of sucrose intake. Conversely, rat pups showed more ingestive, and fewer aversive, responses to the sweet tastant when access to the solution followed the intraoral infusion of quinine. Likewise, intraoral delivery of quinine elicited a more aversive taste reactivity pattern when delivered after the access to sucrose than when presented to sucrose-naïve pups. This research contributes to the analysis of taste reactivity responses during the early ontogeny of the rat and highlights the importance of previous experiences on the subsequent assessment of rewards.

Respuestas de frustración en humanos / Frustration response in humans

La frustración es un estado emocional que se desencadena ante acontecimientos que involucran la reducción o supresión inesperada de reforzadores apetitivos. En este artículo se presentan una serie de trabajos realizados con humanos en los cuales se omiten, devalúan o interrumpen refuerzos alimenticios, monetarios, sociales y juegos de entretenimientos. La mayoría de los resultados experimentales son análogos a los hallados con animales no humanos, aunque agregan información sobre reacciones específicamente humanas, tales como los informes verbales, las expresiones faciales y cómo se regula mediante los estilos atribucionales y la personalidad. Finalmente se discute si la frustración puede o no enmarcarse dentro de las emociones básicas.

Frustration is an emotional state elicitated by the unexpected reduction or suppression of appetitive reinforcers. In this article studies of frustration with humans are presented, in which food, monetary, social reinforcers and entertainment games are either omitted, devaluated or interrupted. The majority of the experimental results are analogous to the results founded with non-human subjects, though they add information about human reactions such as verbal reports, facial expressions, and how these responses are regulated by the contribution of attribution styles and personality. Finally, the possibility of categorizing frustration as one of the basic emotions is also discussed.